subject:(Compton Gamma ray Imaging)

University of California – Berkeley

1. Barnowski, Ross Barnowski. Development and Evaluation of Real-Time Volumetric Compton Gamma-Ray Imaging.

Degree: Nuclear Engineering, 2016, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/6099194w

► An approach to gamma-ray imaging has been developed that enables near real-time volumetric (3D) imaging of unknown environments thus improving the utility of gamma-ray imaging… (more)

Subjects/Keywords: Nuclear physics and radiation; Engineering; 3D Imaging; Compton Imaging; Gamma-Ray Data Fusion; Gamma-Ray Imaging; SLAM; Volumetric Imaging

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APA (6^th Edition):

Barnowski, R. B. (2016). Development and Evaluation of Real-Time Volumetric Compton Gamma-Ray Imaging. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/6099194w

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Barnowski, Ross Barnowski. “Development and Evaluation of Real-Time Volumetric Compton Gamma-Ray Imaging.” 2016. Thesis, University of California – Berkeley. Accessed January 15, 2021. http://www.escholarship.org/uc/item/6099194w.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Barnowski, Ross Barnowski. “Development and Evaluation of Real-Time Volumetric Compton Gamma-Ray Imaging.” 2016. Web. 15 Jan 2021.

Vancouver:

Barnowski RB. Development and Evaluation of Real-Time Volumetric Compton Gamma-Ray Imaging. [Internet] [Thesis]. University of California – Berkeley; 2016. [cited 2021 Jan 15]. Available from: http://www.escholarship.org/uc/item/6099194w.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Barnowski RB. Development and Evaluation of Real-Time Volumetric Compton Gamma-Ray Imaging. [Thesis]. University of California – Berkeley; 2016. Available from: http://www.escholarship.org/uc/item/6099194w

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Arizona

2. Farber, Aaron M. Coded-Aperture Compton Camera for Gamma-Ray Imaging .

Degree: 2013, University of Arizona

URL: http://hdl.handle.net/10150/311555

► This dissertation describes the development of a novel gamma-ray imaging system concept and presents results from Monte Carlo simulations of the new design. Current designs… (more)

Subjects/Keywords: Compton; Gamma-ray imaging; remote sensing; Aerospace Engineering; Coded aperture

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Farber, A. M. (2013). Coded-Aperture Compton Camera for Gamma-Ray Imaging . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/311555

Chicago Manual of Style (16^th Edition):

Farber, Aaron M. “Coded-Aperture Compton Camera for Gamma-Ray Imaging .” 2013. Doctoral Dissertation, University of Arizona. Accessed January 15, 2021. http://hdl.handle.net/10150/311555.

MLA Handbook (7^th Edition):

Farber, Aaron M. “Coded-Aperture Compton Camera for Gamma-Ray Imaging .” 2013. Web. 15 Jan 2021.

Vancouver:

Farber AM. Coded-Aperture Compton Camera for Gamma-Ray Imaging . [Internet] [Doctoral dissertation]. University of Arizona; 2013. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10150/311555.

Council of Science Editors:

Farber AM. Coded-Aperture Compton Camera for Gamma-Ray Imaging . [Doctoral Dissertation]. University of Arizona; 2013. Available from: http://hdl.handle.net/10150/311555

University of California – Berkeley

3. Coffer, Amy Beth. Guiding the Design of Radiation Imagers with Experimentally Benchmarked Geant4 Simulations for Electron-Tracking Compton Imaging.

Degree: Nuclear Engineering, 2016, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/5tg6b3nb

► Radiation imagers are import tools in the modern world for a wide range of applications. They span the use-cases of fundamental sciences, astrophysics, medical imaging,… (more)

Subjects/Keywords: Nuclear engineering; Nuclear physics and radiation; Compton-imaging; electron-tracking Compton imaging; gamma-ray imaging; Geant4; Monte Carlo simulation

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APA (6^th Edition):

Coffer, A. B. (2016). Guiding the Design of Radiation Imagers with Experimentally Benchmarked Geant4 Simulations for Electron-Tracking Compton Imaging. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/5tg6b3nb

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Coffer, Amy Beth. “Guiding the Design of Radiation Imagers with Experimentally Benchmarked Geant4 Simulations for Electron-Tracking Compton Imaging.” 2016. Thesis, University of California – Berkeley. Accessed January 15, 2021. http://www.escholarship.org/uc/item/5tg6b3nb.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Coffer, Amy Beth. “Guiding the Design of Radiation Imagers with Experimentally Benchmarked Geant4 Simulations for Electron-Tracking Compton Imaging.” 2016. Web. 15 Jan 2021.

Vancouver:

Coffer AB. Guiding the Design of Radiation Imagers with Experimentally Benchmarked Geant4 Simulations for Electron-Tracking Compton Imaging. [Internet] [Thesis]. University of California – Berkeley; 2016. [cited 2021 Jan 15]. Available from: http://www.escholarship.org/uc/item/5tg6b3nb.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Coffer AB. Guiding the Design of Radiation Imagers with Experimentally Benchmarked Geant4 Simulations for Electron-Tracking Compton Imaging. [Thesis]. University of California – Berkeley; 2016. Available from: http://www.escholarship.org/uc/item/5tg6b3nb

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

4. Chatzistratis, Dimitrios. Ψηφιδωτά ηλεκτρονικά επεξεργασίας σήματος σε υβριδικούς αισθητήρες ιονιζουσών ακτινοβολιών.

Degree: 2018, University of Patras; Πανεπιστήμιο Πατρών

URL: http://hdl.handle.net/10442/hedi/43346

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In this thesis we will deal with design aspects of a series of CMOS integrated circuits to be used in gamma ray hybrid pixel detectors.… (more)

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In this thesis we will deal with design aspects of a series of CMOS integrated circuits to be used in gamma ray hybrid pixel detectors. These pixel integrated circuits can give in digital format the energy, the time stamp and the address of the interaction that took place in the detection layer of the hybrid.The first and the second member of the series has been manufactured and characterized while the third member has been manufactured and it’s characterization is about to be completed. The hybrid detectors, of which these integrated circuits are a component, are used for the construction of a Compton detector that localize and identify a radioactive source.

Στην παρούσα διδακτορική διατριβή ασχολούμαστε με τη σχεδίαση μιας σειράς CMOS ολοκληρωμένων κυκλωμάτων για χρήση σε υβριδικούς ψηφιδωτούς ανιχνευτές ακτινών γ. Αυτά τα ψηφιδωτά ολοκληρωμένα κυκλώματα είναι σε θέση να δίνουν σε ψηφιακή μορφή την πληροφορία θέσης, ενέργειας και χρόνου της αλληλεπίδρασης που έλαβε χώρα στο στρώμα ανίχνευσης του υβριδικού ανιχνευτή.Το πρώτο και το δεύτερο μέλος της σειράς, κατασκευάσθηκε και χαρακτηρίστηκε, ενώ το τρίτο μέλος κατασκευάσθηκε και βρίσκεται στα τελικά στάδια χαρακτηρισμού. Οι υβριδικοί ανιχνευτές των οποίων τα ολοκληρωμένα κυκλώματα αποτελούν τμήμα, χρησιμοποιούνται για την κατασκευή ανιχνευτή Compton που προσδιορίζει την θέση και την ταυτότητα μιας ραδιενεργού πηγής.

Subjects/Keywords: Ολοκληρωμένα κυκλώματα ανάγνωσης δεδομένων; Ψηφιακή απεικόνιση ακτινών γ; Υβριδικοί ψηφιδωτοί ανιχνευτές; Κάμερα Compton; Read-out integrated circuits; Digital gamma ray imaging; Hybrid pixel detectors; Compton Camera

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APA (6^th Edition):

Chatzistratis, D. (2018). Ψηφιδωτά ηλεκτρονικά επεξεργασίας σήματος σε υβριδικούς αισθητήρες ιονιζουσών ακτινοβολιών. (Thesis). University of Patras; Πανεπιστήμιο Πατρών. Retrieved from http://hdl.handle.net/10442/hedi/43346

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Chatzistratis, Dimitrios. “Ψηφιδωτά ηλεκτρονικά επεξεργασίας σήματος σε υβριδικούς αισθητήρες ιονιζουσών ακτινοβολιών.” 2018. Thesis, University of Patras; Πανεπιστήμιο Πατρών. Accessed January 15, 2021. http://hdl.handle.net/10442/hedi/43346.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Chatzistratis, Dimitrios. “Ψηφιδωτά ηλεκτρονικά επεξεργασίας σήματος σε υβριδικούς αισθητήρες ιονιζουσών ακτινοβολιών.” 2018. Web. 15 Jan 2021.

Vancouver:

Chatzistratis D. Ψηφιδωτά ηλεκτρονικά επεξεργασίας σήματος σε υβριδικούς αισθητήρες ιονιζουσών ακτινοβολιών. [Internet] [Thesis]. University of Patras; Πανεπιστήμιο Πατρών; 2018. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10442/hedi/43346.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chatzistratis D. Ψηφιδωτά ηλεκτρονικά επεξεργασίας σήματος σε υβριδικούς αισθητήρες ιονιζουσών ακτινοβολιών. [Thesis]. University of Patras; Πανεπιστήμιο Πατρών; 2018. Available from: http://hdl.handle.net/10442/hedi/43346

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

5. Plimley, Brian Christopher. Electron Trajectory Reconstruction for Advanced Compton Imaging of Gamma Rays.

Degree: Nuclear Engineering, 2014, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/8mq6304m

► Gamma-ray imaging is useful for detecting, characterizing, and localizing sources in a variety of fields, including nuclear physics, security, nuclear accident response, nuclear medicine, and… (more)

▼ Gamma-ray imaging is useful for detecting, characterizing, and localizing sources in a variety of fields, including nuclear physics, security, nuclear accident response, nuclear medicine, and astronomy. Compton imaging in particular provides sensitivity to weak sources and good angular resolution in a large field of view. However, the photon origin in a single event sequence is normally only limited to the surface of a cone. If the initial direction of the Compton-scattered electron can be measured, the cone can be reduced to a cone segment with width depending on the uncertainty in the direction measurement, providing a corresponding increase in imaging sensitivity.Measurement of the electron's initial direction in an efficient detection material requires very fine position resolution due to the electron's short range and tortuous path. A thick (650 μm), fully-depleted charge-coupled device (CCD) developed for infrared astronomy has 10.5-μm position resolution in two dimensions, enabling the initial trajectory measurement of electrons of energy as low as 100 keV. This is the first time the initial trajectories of electrons of such low energies have been measured in a solid material. In this work, the CCD's efficacy as a gamma-ray detector is demonstrated experimentally, using a reconstruction algorithm to measure the initial electron direction from the CCD track image. In addition, models of fast electron interaction physics, charge transport and readout were used to generate modeled tracks with known initial direction. These modeled tracks allowed the development and refinement of the reconstruction algorithm. The angular sensitivity of the reconstruction algorithm is evaluated extensively with models for tracks below 480 keV, showing a FWHM as low as 20° in the pixel plane, and 30° RMS sensitivity to the magnitude of the out-of-plane angle.The measurement of the trajectories of electrons with energies as low as 100 keV have the potential to make electron track Compton imaging an effective means of reducing image background for photons of energy as low as 500 keV, or even less.The angular sensitivity of the reconstruction algorithm was also evaluated experimentally, by measuring electron tracks in the CCD in coincidence with the scattered photon in a germanium double-sided strip detector. By this method, electron tracks could be measured with the true initial direction known to within 3° FWHM, and the angular response of the algorithm compared to the known direction. The challenge of this experiment lay in the low geometric efficiency for photons scattering into the germanium, the poor time resolution in the current CCD implementation, and the resulting signal-to-background ratio of about 10^-4 for photons scattered from the CCD into the germanium detector. Nonetheless, 87 events were measured in the FWHM of the total energy deposited and the angular resolution measure, with electron tracks between 160 keV and 360 keV in energy. The electron tracks from true coincident event…

Subjects/Keywords: Nuclear engineering; Nuclear physics; charge-coupled device; Compton imaging; electron track; gamma-ray imaging

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APA (6^th Edition):

Plimley, B. C. (2014). Electron Trajectory Reconstruction for Advanced Compton Imaging of Gamma Rays. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/8mq6304m

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Plimley, Brian Christopher. “Electron Trajectory Reconstruction for Advanced Compton Imaging of Gamma Rays.” 2014. Thesis, University of California – Berkeley. Accessed January 15, 2021. http://www.escholarship.org/uc/item/8mq6304m.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Plimley, Brian Christopher. “Electron Trajectory Reconstruction for Advanced Compton Imaging of Gamma Rays.” 2014. Web. 15 Jan 2021.

Vancouver:

Plimley BC. Electron Trajectory Reconstruction for Advanced Compton Imaging of Gamma Rays. [Internet] [Thesis]. University of California – Berkeley; 2014. [cited 2021 Jan 15]. Available from: http://www.escholarship.org/uc/item/8mq6304m.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Plimley BC. Electron Trajectory Reconstruction for Advanced Compton Imaging of Gamma Rays. [Thesis]. University of California – Berkeley; 2014. Available from: http://www.escholarship.org/uc/item/8mq6304m

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

6. Gostojić, Aleksandar. Développement d'un télescope Comton avec un calorimètre imageur 3D pour l'astronomie gamma : Development of a Compton Telescope with 3D Imaging Calorimeter for Gamma-Ray Astronomy.

Degree: Docteur es, Astrophysique nucléaire et nucléosynthèse, 2016, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2016SACLS136

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La thèse porte sur le développement d’un petit prototype de télescope Compton pour l'astronomie gamma spatiale dans la gamme d’énergie du MeV (0.1-100 MeV). Nous… (more)

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La thèse porte sur le développement d’un petit prototype de télescope Compton pour l'astronomie gamma spatiale dans la gamme d’énergie du MeV (0.1-100 MeV). Nous avons étudié de nouveaux modules de détection destinés à l'imagerie Compton. Nous avons assemblé et testé deux détecteurs à scintillation, l'un avec un cristal de bromure de lanthane dopé au cérium (LaBr₃:Ce) et l'autre avec un cristal de bromure de cérium (CeBr₃). Les deux cristaux sont couplés à des photomultiplicateurs multi-anodes 64 voies sensibles à la position. Notre objectif est d’optimiser la résolution en énergie en même temps que la résolution en position du premier impact d'un rayon gamma incident dans le détecteur. Les deux informations sont vitales pour la reconstruction d'une image avec le prototype de télescope à partir de l’effet Compton. Nous avons développé un banc de test pour étudier expérimentalement les deux modules, avec une électronique de lecture et un système d'acquisition de données dédiés. Nous avons entrepris un étalonnage précis du dispositif et effectué de nombreuses mesures avec différentes sources radioactives. En outre, nous avons réalisé une simulation numérique détaillée de l'expérience avec le logiciel GEANT4 et effectué une étude paramétrique extensive pour modéliser au mieux la propagation des photons ultraviolet de scintillation et les propriétés optiques des surfaces à l'intérieur du détecteur. Nous avons alors développé une méthode originale de reconstruction de la position d’impact en 3D, en utilisant un réseau de neurones artificiels entrainé avec des données simulées. Nous présentons dans ce travail tous les résultats expérimentaux obtenus avec les deux modules, les résultats de la simulation GEANT4, ainsi que l'algorithme basé sur le réseau de neurones. En plus, nous donnons les premiers résultats sur l'imagerie Compton obtenus avec le prototype de télescope et les comparons avec des performances simulées. Enfin, nous concluons en donnant un aperçu des perspectives d'avenir pour l'imagerie gamma Compton et considérons une application possible en discutant d’un concept de télescope spatial semblable à notre prototype.

The thesis aims to develop a small prototype of a Compton telescope for future space instrumentation for gamma-ray astronomy. Telescope’s main target is the MeV range (0.1-100MeV). We studied novel detector modules intended for Compton imaging. We assembled and tested 2 modules, one with a cerium-doped lanthanum(III) bromide (LaBr₃:Ce) crystal and the other with cerium(III) bromide (CeBr₃). Both modules are coupled to and read out by 64-channel multi-anode PMTs. Our goals are to obtain the best possible energy resolution and position resolution in 3D on the first impact of an incident gamma-ray within the detector. Both information are vital for successful reconstruction of a Compton image with the telescope prototype. We developed a test bench to experimentally study both modules and have utilized a customized readout electronics and data acquisition system. We conducted a precise calibration of…

Advisors/Committee Members: Tatischeff, Vincent (thesis director).

Subjects/Keywords: Astronomie gamma; Télescope Compton; Imagerie gamma; Détecteurs; Scintillateurs; Simulation par ordinateur - Logiciels; Réseau de neurones; Gamma-ray astronomy; Compton telescope; Gamma-ray imaging; Detectors; Scintillators; Computer simulation - Software; Neural networks

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gostojić, A. (2016). Développement d'un télescope Comton avec un calorimètre imageur 3D pour l'astronomie gamma : Development of a Compton Telescope with 3D Imaging Calorimeter for Gamma-Ray Astronomy. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2016SACLS136

Chicago Manual of Style (16^th Edition):

Gostojić, Aleksandar. “Développement d'un télescope Comton avec un calorimètre imageur 3D pour l'astronomie gamma : Development of a Compton Telescope with 3D Imaging Calorimeter for Gamma-Ray Astronomy.” 2016. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 15, 2021. http://www.theses.fr/2016SACLS136.

MLA Handbook (7^th Edition):

Gostojić, Aleksandar. “Développement d'un télescope Comton avec un calorimètre imageur 3D pour l'astronomie gamma : Development of a Compton Telescope with 3D Imaging Calorimeter for Gamma-Ray Astronomy.” 2016. Web. 15 Jan 2021.

Vancouver:

Gostojić A. Développement d'un télescope Comton avec un calorimètre imageur 3D pour l'astronomie gamma : Development of a Compton Telescope with 3D Imaging Calorimeter for Gamma-Ray Astronomy. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2016. [cited 2021 Jan 15]. Available from: http://www.theses.fr/2016SACLS136.

Council of Science Editors:

Gostojić A. Développement d'un télescope Comton avec un calorimètre imageur 3D pour l'astronomie gamma : Development of a Compton Telescope with 3D Imaging Calorimeter for Gamma-Ray Astronomy. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2016. Available from: http://www.theses.fr/2016SACLS136

University of New Mexico

7. Tornga, Shawn. MOBILE, HYBRID COMPTON/CODED APERTURE IMAGING FOR DETECTION, IDENTIFICATION AND LOCALIZATION OF GAMMA-RAY SOURCES AT STAND-OFF DISTANCES.

Degree: Nuclear Engineering, 2013, University of New Mexico

URL: http://hdl.handle.net/1928/23158

► The Stand-off radiation detection system (SORDS) program is an advanced technology demonstration (ATD) project through the Domestic Nuclear Detection Office (DNDO) with the goal of… (more)

▼ The Stand-off radiation detection system (SORDS) program is an advanced technology demonstration (ATD) project through the Domestic Nuclear Detection Office (DNDO) with the goal of detection, identification and localization of weak radiological sources in the presence of large dynamic backgrounds. The Raytheon-Tri-Modal Imager (TMI) is a mobile truck-based, hybrid gamma-ray spectroscopic and imaging system able to quickly detect, identify and localize, radiation sources at standoff distances through improved sensitivity provided by multiple detection modes while minimizing the false alarm rate. Reconstruction of gamma-ray sources is performed using a combination of gamma-ray spectroscopy and two imaging modalities; coded aperture and Compton scatter imaging. The TMI consists of 35 NaI crystals (5x5x2 in each), arranged in a random coded aperture CA, followed by 30 position sensitive NaI bars (24x2.5x3 in each) called the DA. The CA array acts as both a coded aperture mask and scattering detector for Compton events. The large-area DA array acts as a collection detector for both Compton scattered events and coded aperture events. In this thesis, the implemented spectroscopic, coded aperture, Compton and hybrid imaging algorithms will be described along with their performance. It will be shown that multiple imaging modalities can be fused to improve detection sensitivity over a broader energy range than any mode alone. Since the TMI is a moving system, peripheral data, such as a GPS and INS must also be incorporated. A method of adapting static imaging algorithms to a moving platform has been developed. Also, algorithms were developed in parallel with detector hardware, through the use of extensive simulations performed with the GEANT4. Simulations have been well validated against measured data. Results of image reconstruction algorithms at various speeds and distances will be presented as well as localization capability. Utilizing imaging information will show signal-to-noise gains over spectroscopic algorithms alone. Advisors/Committee Members: Hecht, Adam, Hecht, Adam, Fields, Douglas, Cooper, Gary, Sullivan, John.

Subjects/Keywords: gamma-ray; imaging; hybrid; coded aperture; compton; spectroscopic; SORDS; DNDO; homeland security

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tornga, S. (2013). MOBILE, HYBRID COMPTON/CODED APERTURE IMAGING FOR DETECTION, IDENTIFICATION AND LOCALIZATION OF GAMMA-RAY SOURCES AT STAND-OFF DISTANCES. (Doctoral Dissertation). University of New Mexico. Retrieved from http://hdl.handle.net/1928/23158

Chicago Manual of Style (16^th Edition):

Tornga, Shawn. “MOBILE, HYBRID COMPTON/CODED APERTURE IMAGING FOR DETECTION, IDENTIFICATION AND LOCALIZATION OF GAMMA-RAY SOURCES AT STAND-OFF DISTANCES.” 2013. Doctoral Dissertation, University of New Mexico. Accessed January 15, 2021. http://hdl.handle.net/1928/23158.

MLA Handbook (7^th Edition):

Tornga, Shawn. “MOBILE, HYBRID COMPTON/CODED APERTURE IMAGING FOR DETECTION, IDENTIFICATION AND LOCALIZATION OF GAMMA-RAY SOURCES AT STAND-OFF DISTANCES.” 2013. Web. 15 Jan 2021.

Vancouver:

Tornga S. MOBILE, HYBRID COMPTON/CODED APERTURE IMAGING FOR DETECTION, IDENTIFICATION AND LOCALIZATION OF GAMMA-RAY SOURCES AT STAND-OFF DISTANCES. [Internet] [Doctoral dissertation]. University of New Mexico; 2013. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/1928/23158.

Council of Science Editors:

Tornga S. MOBILE, HYBRID COMPTON/CODED APERTURE IMAGING FOR DETECTION, IDENTIFICATION AND LOCALIZATION OF GAMMA-RAY SOURCES AT STAND-OFF DISTANCES. [Doctoral Dissertation]. University of New Mexico; 2013. Available from: http://hdl.handle.net/1928/23158

University of California – Berkeley

8. Bellm, Eric Christopher. Studies of Gamma-Ray Burst Prompt Emission with RHESSI and NCT.

Degree: Physics, 2011, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/4641m3kn

► Gamma-Ray Bursts (GRBs) are the most luminous objects in the universe. They herald a catastrophic energy release which manifests itself in tenths to hundreds of… (more)

▼ Gamma-Ray Bursts (GRBs) are the most luminous objects in the universe. They herald a catastrophic energy release which manifests itself in tenths to hundreds of seconds of irregular gamma-ray emission. This initial "prompt" emission is followed by "afterglow" emission at other wavelengths that fades smoothly over hours to years. GRB prompt emission has been observed with ever-increasing sophistication for more than four decades, but many details of its origin remain unknown. While GRBs are under-stood to result from relativistic jets produced by violent reconfigurations of compact objects, the composition of the outflow, the means of energy dissipation, and the radiative processes underlying the observed emission are all uncertain. I review the present understanding of all facets of GRB science in Chapter 1. Gamma-ray spectroscopy and polarimetry provide two channels for testing models of GRB prompt emission with observed data. In Chapters 2-4, I employ the Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) to conduct broad-band time-resolved spectroscopy of bright GRBs. RHESSI is a solar observatory that uses nine coaxial germanium detectors for imaging and spectroscopy of solar flares. Because the detectors are unshielded, RHESSI also records counts from off-axis sources like GRBs. In Chapter 2, I detail the methods I use for analyzing RHESSI GRB data. In Chapter 3, I conduct joint spectral analysis of bursts co-observed by RHESSI and Swift-BAT, enabling spectral modeling over a wide 15 keV-17 MeV band. These results reveal the difficulty of predicting the peak spectral energy of a burst from BAT observations alone. While GRB spectra commonly have been assumed to be non-thermal and have been fit by purely phenomenological models, some authors have proposed that thermal emission from the GRB photosphere may be the source of the GRB spectral peak. In Chapter 4, I perform time-resolved spectroscopy of bright GRBs observed by RHESSI and compare the fit results of several phenomenological and quasi-thermal models. The fit results for the quasi-thermal models are poorer than those reported for fits in more narrow energy bands, and the fit parameters show significant dependence on the fit band. More sophisticated models and additional data are needed to determine the relevance of the photospheric emission.Polarimetric studies of GRBs are in their infancy, but they have the potential to distinguish GRB emission models and probe the structure of the relativistic jet. Observations to date have exploited the polarimetric signatures produced by Compton scattering in gamma-ray observatories. Since these instruments have poor spatial resolution and are not calibrated for polarimetric observations, only a few bright GRBs have been observed, each with significant systematic effects. In Chapters 5-8, I present development work for a balloon-borne Compton telescope, the Nuclear Compton Telescope (NCT), which is capable of measuring GRB polarization. NCT uses planar cross-strip germanium detectors for Compton imaging (200…

Subjects/Keywords: Astrophysics; Compton telescopes; gamma-ray astrophysics; gamma-ray bursts; polarimetry; spectroscopy

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APA (6^th Edition):

Bellm, E. C. (2011). Studies of Gamma-Ray Burst Prompt Emission with RHESSI and NCT. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/4641m3kn

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bellm, Eric Christopher. “Studies of Gamma-Ray Burst Prompt Emission with RHESSI and NCT.” 2011. Thesis, University of California – Berkeley. Accessed January 15, 2021. http://www.escholarship.org/uc/item/4641m3kn.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bellm, Eric Christopher. “Studies of Gamma-Ray Burst Prompt Emission with RHESSI and NCT.” 2011. Web. 15 Jan 2021.

Vancouver:

Bellm EC. Studies of Gamma-Ray Burst Prompt Emission with RHESSI and NCT. [Internet] [Thesis]. University of California – Berkeley; 2011. [cited 2021 Jan 15]. Available from: http://www.escholarship.org/uc/item/4641m3kn.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bellm EC. Studies of Gamma-Ray Burst Prompt Emission with RHESSI and NCT. [Thesis]. University of California – Berkeley; 2011. Available from: http://www.escholarship.org/uc/item/4641m3kn

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Kyoto University / 京都大学

9. Komura, Shotaro. Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera : 電子飛跡検出型コンプトンカメラを用いたサブMeVガンマ線全天探査のための撮像偏光計.

Degree: 博士(理学), 2018, Kyoto University / 京都大学

URL: http://hdl.handle.net/2433/230989 ; http://dx.doi.org/10.14989/doctor.k20786

新制・課程博士

甲第20786号

理博第4330号

Subjects/Keywords: Imaging Polarimeter; Sub-MeV Gamma-Ray; Compton Camera

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Komura, S. (2018). Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera : 電子飛跡検出型コンプトンカメラを用いたサブMeVガンマ線全天探査のための撮像偏光計. (Thesis). Kyoto University / 京都大学. Retrieved from http://hdl.handle.net/2433/230989 ; http://dx.doi.org/10.14989/doctor.k20786

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Komura, Shotaro. “Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera : 電子飛跡検出型コンプトンカメラを用いたサブMeVガンマ線全天探査のための撮像偏光計.” 2018. Thesis, Kyoto University / 京都大学. Accessed January 15, 2021. http://hdl.handle.net/2433/230989 ; http://dx.doi.org/10.14989/doctor.k20786.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Komura, Shotaro. “Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera : 電子飛跡検出型コンプトンカメラを用いたサブMeVガンマ線全天探査のための撮像偏光計.” 2018. Web. 15 Jan 2021.

Vancouver:

Komura S. Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera : 電子飛跡検出型コンプトンカメラを用いたサブMeVガンマ線全天探査のための撮像偏光計. [Internet] [Thesis]. Kyoto University / 京都大学; 2018. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2433/230989 ; http://dx.doi.org/10.14989/doctor.k20786.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Komura S. Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera : 電子飛跡検出型コンプトンカメラを用いたサブMeVガンマ線全天探査のための撮像偏光計. [Thesis]. Kyoto University / 京都大学; 2018. Available from: http://hdl.handle.net/2433/230989 ; http://dx.doi.org/10.14989/doctor.k20786

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

10. Komura, Shotaro. Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera .

Degree: 2018, Kyoto University

URL: http://hdl.handle.net/2433/230989

Subjects/Keywords: Imaging Polarimeter; Sub-MeV Gamma-Ray; Compton Camera

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Komura, S. (2018). Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera . (Thesis). Kyoto University. Retrieved from http://hdl.handle.net/2433/230989

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Komura, Shotaro. “Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera .” 2018. Thesis, Kyoto University. Accessed January 15, 2021. http://hdl.handle.net/2433/230989.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Komura, Shotaro. “Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera .” 2018. Web. 15 Jan 2021.

Vancouver:

Komura S. Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera . [Internet] [Thesis]. Kyoto University; 2018. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2433/230989.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Komura S. Imaging Polarimeter for a Sub-MeV Gamma-Ray All-sky Survey Using an Electron-tracking Compton Camera . [Thesis]. Kyoto University; 2018. Available from: http://hdl.handle.net/2433/230989

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université Paris-Sud – Paris XI

11. Dupraz, Kevin. Conception et optimisation d’un recirculateur optique pour la source haute brillance de rayons gamma d’ELI-NP : Design and optimization of an optical Laser Beam Circulator for the high brillance gamma-ray source of ELI-NP.

Degree: Docteur es, Physique, 2015, Université Paris-Sud – Paris XI

URL: http://www.theses.fr/2015PA112218

►

Cette thèse porte sur la conception et la réalisation du système optique d'une nouvelle source de rayonnement gamma, ELI-NP-GBS (Extreme Light Infrastructure - Nuclear Physics… (more)

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Cette thèse porte sur la conception et la réalisation du système optique d'une nouvelle source de rayonnement gamma, ELI-NP-GBS (Extreme Light Infrastructure - Nuclear Physics - Gamma Beam Source), qui utilise des développements récents des technologies des lasers, de l'optique et des accélérateurs. Les caractéristiques finales que devra atteindre cette source sont au moins d'un ordre de grandeur, en intensité, supérieur à la meilleure machine Compton actuelle, HIGS. Un nouveau type de système optique a été conçu pour ELI-NP-GBS. Il s'agit d'un système à 32 passages composé de deux miroirs paraboliques confocaux et d'un ensemble de paires de miroirs. Les miroirs paraboliques permettent la focalisation et la collimation successives d'un faisceau laser de haute intensité (400 mJ par impulsion). La géométrie "dragon-shape" garantie que le croisement du faisceau laser avec le faisceau d'électron se produise avec un angle constant en un point unique. De telles performances sont assurées par un alignement des éléments optiques à mieux que quelques micromètres en position et quelques microradians en orientation et une synchronisation de tous les passages avec les paquets d'électrons à mieux que quelques centaines de femtosecondes. Cet alignement et cette synchronisation est obtenue par l'intermédiaire de procédures et d'algorithmes spécialement développés pour ce système. Les algorithmes ont ainsi été développés et testés sur des simulations numériques dédiées prenant en compte les aspects mécaniques et optiques du système tel que les pré-alignements mécaniques, les états de surfaces des miroirs, la polarisation du faisceau laser, etc. Une première preuve de principe de la méthode de synchronisation a été concluante.

This thesis is about the design and the realization of the optical system of a new gamma-ray source, ELI-NP-GBS (Extreme Light Infrastructure - Nuclear Physics - Gamma Beam Source), which benefits from the recent developments in laser technology, optics and accelerators. The final characteristics that this source aims to reach is one order of magnitude higher in intensity than the actual best Compton machine, HIGS. A new type of optical system has been designed for ELI-NP-GBS. It is a 32 passes system made of two confocal parabolic mirrors and a set of Mirror-Pair Systems. The parabolic reflectors focalize and collimate successively a high intensity laser beam (400 mJ per pulse). The ``dragon-shape'' geometry ensures that the laser beam and electron bunches cross at a constant angle in a unique point. These performances are guaranteed by a few micrometers precision in position alignment, a few microradians precision in orientation alignment and by a few hundreds femtoseconds synchronization between electron bunches and laser pulses for each pass. This alignment and this synchronization is performed by used of dedicated procedures and algorithms. These algorithms have been developed and tested with numerical simulations which take into account the mechanical and optical aspects of the system such as the…

Advisors/Committee Members: Zomer, Fabian (thesis director).

Subjects/Keywords: Optique; Diffusion Compton; Conception; Rayons gamma; Optimisation; Optics; Compton scattering; Design; Gamma-ray; Optimization

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dupraz, K. (2015). Conception et optimisation d’un recirculateur optique pour la source haute brillance de rayons gamma d’ELI-NP : Design and optimization of an optical Laser Beam Circulator for the high brillance gamma-ray source of ELI-NP. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2015PA112218

Chicago Manual of Style (16^th Edition):

Dupraz, Kevin. “Conception et optimisation d’un recirculateur optique pour la source haute brillance de rayons gamma d’ELI-NP : Design and optimization of an optical Laser Beam Circulator for the high brillance gamma-ray source of ELI-NP.” 2015. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed January 15, 2021. http://www.theses.fr/2015PA112218.

MLA Handbook (7^th Edition):

Dupraz, Kevin. “Conception et optimisation d’un recirculateur optique pour la source haute brillance de rayons gamma d’ELI-NP : Design and optimization of an optical Laser Beam Circulator for the high brillance gamma-ray source of ELI-NP.” 2015. Web. 15 Jan 2021.

Vancouver:

Dupraz K. Conception et optimisation d’un recirculateur optique pour la source haute brillance de rayons gamma d’ELI-NP : Design and optimization of an optical Laser Beam Circulator for the high brillance gamma-ray source of ELI-NP. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2015. [cited 2021 Jan 15]. Available from: http://www.theses.fr/2015PA112218.

Council of Science Editors:

Dupraz K. Conception et optimisation d’un recirculateur optique pour la source haute brillance de rayons gamma d’ELI-NP : Design and optimization of an optical Laser Beam Circulator for the high brillance gamma-ray source of ELI-NP. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2015. Available from: http://www.theses.fr/2015PA112218

12. Yassine, Manal. The prompt emission of Gamma-Ray Bursts : analysis and interpretation of Fermi observations : L'émission prompte des sursauts gamma : analyse et interprétation des observations de Fermi.

Degree: Docteur es, Physique, 2017, Montpellier

URL: http://www.theses.fr/2017MONTS006

► Les sursauts gamma (GRBs pour "Gamma-Ray Bursts" en anglais) sont de brèves bouffées très énergétiques de rayonnement de haute énergie qui sont émises sur de… (more)

▼ Les sursauts gamma (GRBs pour "Gamma-Ray Bursts" en anglais) sont de brèves bouffées très énergétiques de rayonnement de haute énergie qui sont émises sur de courtes échelles de temps (fraction de seconde à plusieurs minutes). L'émission intense des sursauts gamma à haute énergie est supposée provenir d'un trou noir de masse stellaire nouvellement formé, accompagné d'un vent collimaté (i.e. un jet) se propageant à vitesse relativiste. L'émission est observée suivant deux phases successives, la phase prompte très erratique, et la phase de rémanence, moins lumineuse. Les deux instruments embarqués sur le satellite Fermi, le "Gamma-ray Burst Monitor" (GBM) et le "Large Area Telescope" (LAT), permettent d'étudier l'émission prompte des sursauts gamma sur une grande plage d'énergie (de ~10 keV à ~100 GeV). L'objectif principal de ma thèse est l'analyse et l'interprétation des propriétés spectrales et temporelles de l'émission prompte des GRBs observés par Fermi, en particulier avec les nouvelles données du LAT (Pass 8) qui ont été rendues publiques en juin 2015.La première partie de mon travail est une analyse spectrale résolue en temps de la phase prompte du sursaut GRB 090926A avec les données du GBM et du LAT. Mes résultats confirment avec un meilleur niveau de confiance la présence d'une cassure spectrale à ~400 MeV, qui est observée en coincidence avec un pic d'émission très court. Ils révèlent que cette atténuation spectrale est présente durant toute l'émission prompte du sursaut, et que l'énergie de cassure augmente jusqu'au GeV. L'interprétation de la cassure spectrale en termes d'absorption gamma ou de courbure naturelle du spectre d'émission Compton inverse (CI) dans le régime Klein-Nishina fournit des contraintes fortes sur le facteur de Lorentz du jet. Mes résultats conduisent en outre à des rayons d'émission R ∼10¹⁴ cm qui sont compatibles avec une origine interne de l'émission du keV au GeV au-dessus de la photosphère du jet.La seconde partie de mon travail est une exploration du modèle de chocs internes développé par des collaborateurs à l'Institut d'Astrophysique de Paris (IAP). Ce modèle simule la dynamique du jet et les processus d'émission (synchrotron et CI) d'une population d'électrons accélérés aux chocs. J'ai simulé la réponse instrumentale de Fermi à un sursaut synthétique fourni par ce code numérique, et j'ai construit une fonction paramétrique qui peut être utilisée pour ajuster le modèle aux spectres de sursauts du keV au MeV. J'ai appliqué cette fonction avec succès à un échantillon de 64 sursauts brillants détectés par le GBM. J'ai aussi confronté le modèle de l'IAP au spectre d'émission prompte de GRB 090926A. Mes résultats montrent un bon accord, et j'ai identifié quelques pistes pour les améliorer. Les spectres synthétiques sont plus larges que tous les spectres dans l'échantillon du GBM. En conséquence, je discute brièvement quelques pistes de développements théoriques qui pourraient améliorer l'accord du modèle avec les observations, ainsi que des avancées observationnelles attendues… Advisors/Committee Members: Piron, Frédéric (thesis director).

Subjects/Keywords: Sursauts gamma; Émission prompte; Opacité γ à la création de paires; Facteur de Lorentz du jet; Émissions synchrotron et Compton inverse; Satellite Fermi; Gamma-Ray bursts; Prompt emission; Γ-Ray opacity to pair creation; Jet Lorentz factor; Synchrotron and inverse Compton radiations; Fermi gamma-Ray space telescope

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Yassine, M. (2017). The prompt emission of Gamma-Ray Bursts : analysis and interpretation of Fermi observations : L'émission prompte des sursauts gamma : analyse et interprétation des observations de Fermi. (Doctoral Dissertation). Montpellier. Retrieved from http://www.theses.fr/2017MONTS006

Chicago Manual of Style (16^th Edition):

Yassine, Manal. “The prompt emission of Gamma-Ray Bursts : analysis and interpretation of Fermi observations : L'émission prompte des sursauts gamma : analyse et interprétation des observations de Fermi.” 2017. Doctoral Dissertation, Montpellier. Accessed January 15, 2021. http://www.theses.fr/2017MONTS006.

MLA Handbook (7^th Edition):

Yassine, Manal. “The prompt emission of Gamma-Ray Bursts : analysis and interpretation of Fermi observations : L'émission prompte des sursauts gamma : analyse et interprétation des observations de Fermi.” 2017. Web. 15 Jan 2021.

Vancouver:

Yassine M. The prompt emission of Gamma-Ray Bursts : analysis and interpretation of Fermi observations : L'émission prompte des sursauts gamma : analyse et interprétation des observations de Fermi. [Internet] [Doctoral dissertation]. Montpellier; 2017. [cited 2021 Jan 15]. Available from: http://www.theses.fr/2017MONTS006.

Council of Science Editors:

Yassine M. The prompt emission of Gamma-Ray Bursts : analysis and interpretation of Fermi observations : L'émission prompte des sursauts gamma : analyse et interprétation des observations de Fermi. [Doctoral Dissertation]. Montpellier; 2017. Available from: http://www.theses.fr/2017MONTS006

University of Michigan

13. Zhang, Lisha. Compton gamma -ray imaging probes for prostate and breast.

Degree: PhD, Medical imaging, 2004, University of Michigan

URL: http://hdl.handle.net/2027.42/124603

► Radionuclide imaging provides valuable functional information that cannot be obtained using anatomical imagers. Consequently, it has been successfully used in detecting tumors and monitoring disease… (more)

▼ Radionuclide imaging provides valuable functional information that cannot be obtained using anatomical imagers. Consequently, it has been successfully used in detecting tumors and monitoring disease recurrence and response to therapy. However, conventional single photon imaging systems have spatial resolution in the 1 – 2 cm range for imaging objects at distances 8 to 10 cm. It is important to improve spatial resolution in order to detect tumor as early as possible when treatment is more effective. However, conventional imaging system can improve spatial resolution only at the expense of sensitivity and increased statistical image noise. The proposed Compton imaging technique does not require collimators to form images so that sensitivity is decoupled from spatial resolution. Furthermore, Compton imagers have better performance as gamma-ray energy increases in direct contrast to collimator performance. Probes based on the Compton imaging technique can achieve simultaneous high spatial resolution and high sensitivity over a wide range of energies from 141 keV and above. In this thesis, potential Compton probe designs and their performance in prostate and breast imaging are evaluated using data generated by clinical situation. Images reconstructed using EM algorithm are evaluated using both resolution and sensitivity criteria and observer models to predict detection sensitivity. Results show that the proposed prostate imaging probes achieve absolute detection efficiency of 0.17%, a two-order-magnitude improvement over the mechanically collimated systems, and spatial resolution of 2.4 mm FWHM for ¹¹¹In. An 8 mm tumor with TB ratio of 5:1 is clearly detectable in the reconstructed prostate images, but invisible in the single photon emission computed tomography (SPECT) images. With the same imaging time, the prostate probes have an improved SNR of 3 – 3.5x over the SPECT for detecting both 5 mm and 8 mm tumors. The probe for breast imaging reveals a moderate improvement over a dedicated scintimammographic system in detecting a 5 mm tumor and comparable performance in the detection of an 8 mm tumor. Advisors/Committee Members: Rogers, W. Leslie (advisor), Clinthorne, Neal H. (advisor).

Subjects/Keywords: Breast Imaging; Compton Gamma-ray Imaging; Gamma-rays; Imaging Probes; Medical Imaging; Prostate Imaging

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhang, L. (2004). Compton gamma -ray imaging probes for prostate and breast. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/124603

Chicago Manual of Style (16^th Edition):

Zhang, Lisha. “Compton gamma -ray imaging probes for prostate and breast.” 2004. Doctoral Dissertation, University of Michigan. Accessed January 15, 2021. http://hdl.handle.net/2027.42/124603.

MLA Handbook (7^th Edition):

Zhang, Lisha. “Compton gamma -ray imaging probes for prostate and breast.” 2004. Web. 15 Jan 2021.

Vancouver:

Zhang L. Compton gamma -ray imaging probes for prostate and breast. [Internet] [Doctoral dissertation]. University of Michigan; 2004. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2027.42/124603.

Council of Science Editors:

Zhang L. Compton gamma -ray imaging probes for prostate and breast. [Doctoral Dissertation]. University of Michigan; 2004. Available from: http://hdl.handle.net/2027.42/124603

14. Julien, Manuel Grégory. Development of a FAst Compton TELescope (FACTEL).

Degree: PhD, 2015, University of New Hampshire

URL: https://scholars.unh.edu/dissertation/2208

► This dissertation describes the development of a FAst Compton TELescope (FACTEL) instrument. It is designed to be the prototype of a larger Advanced Scintillators COmpton… (more)

Subjects/Keywords: Compton Telescopes; Gamma ray; Lanthanum Bromine; Scintillators; Time of Flight; Astrophysics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Julien, M. G. (2015). Development of a FAst Compton TELescope (FACTEL). (Doctoral Dissertation). University of New Hampshire. Retrieved from https://scholars.unh.edu/dissertation/2208

Chicago Manual of Style (16^th Edition):

Julien, Manuel Grégory. “Development of a FAst Compton TELescope (FACTEL).” 2015. Doctoral Dissertation, University of New Hampshire. Accessed January 15, 2021. https://scholars.unh.edu/dissertation/2208.

MLA Handbook (7^th Edition):

Julien, Manuel Grégory. “Development of a FAst Compton TELescope (FACTEL).” 2015. Web. 15 Jan 2021.

Vancouver:

Julien MG. Development of a FAst Compton TELescope (FACTEL). [Internet] [Doctoral dissertation]. University of New Hampshire; 2015. [cited 2021 Jan 15]. Available from: https://scholars.unh.edu/dissertation/2208.

Council of Science Editors:

Julien MG. Development of a FAst Compton TELescope (FACTEL). [Doctoral Dissertation]. University of New Hampshire; 2015. Available from: https://scholars.unh.edu/dissertation/2208

University of California – Berkeley

15. Lowell, Alexander. Polarimetric Studies of the Long Duration Gamma-Ray Burst GRB 160530A with the Compton Spectrometer and Imager.

Degree: Physics, 2017, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/3b8664q5

► Gamma-ray bursts (GRBs) are highly luminous flashes of gamma-rays that last from hundreds of milliseconds up to hundreds of seconds, peak in the soft gamma-ray… (more)

▼ Gamma-ray bursts (GRBs) are highly luminous flashes of gamma-rays that last from hundreds of milliseconds up to hundreds of seconds, peak in the soft gamma-ray band 0.1 MeV to 1 MeV, represent ultra-relativistic motion, and originate from cosmological distances. Despite thousands of observations of GRB prompt emission, and hundreds of observations of GRB afterglows, many details pertaining to the nature of gamma-ray bursts remain elusive. A wide variety of models exist that describe the progenitors, central engines, emission mechanism, geometric structure, and magnetization of GRBs. Polarization measurements of the GRB prompt emission are believed to give essential clues where spectral and temporal observations fall short. The Compton Spectrometer and Imager (COSI) is a balloon borne Compton polarimeter, imager, and spectrometer sensitive in the 0.2 MeV to 5 MeV band. One of COSI's main science goals is measuring the polarization of astrophysical gamma-ray sources, including GRBs. Polarimetric measurements with a Compton polarimeter are possible due to the sensitivity of the Compton scattering cross section upon the orientation of the photon's electric field vector. We verified COSI's polarimetric capabilities in the laboratory using partially polarized and unpolarized beams, and compared the measurements to simulations. Overall, the measurements reflect the simulations closely, and we were able to place upper limits on the systematic error on the polarization level of 3% - 4%.In May of 2016, COSI took flight from Wanaka, New Zealand aboard a NASA Super Pressure Balloon. COSI continuously telemetered science data for 46 days before landing in Southern Peru. On May 30, 2016, COSI clearly detected the long duration gamma-ray burst GRB 160530A. We performed a polarization analysis of this GRB using both a standard method (SM) and a maximum likelihood method (MLM). The measured polarization level was below the 99% confidence minimum detectable polarization level (MDP) using both analysis methods (MDP = 72.3% +/- 0.8% for the SM, and MDP = 57.5% +/- 0.8% for the MLM), so we claim a non-detection of polarization for this GRB. Using the MLM, we placed a 90% confidence upper limit of 46% on the polarization level. GRBs with polarization levels higher than 46% have been reported in the literature, and so this result will be useful in future meta-analyses that consider the statistical distribution of polarization levels across the GRB population.

Subjects/Keywords: Astrophysics; balloon; compton scattering; gamma-ray burst; polarimeter

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lowell, A. (2017). Polarimetric Studies of the Long Duration Gamma-Ray Burst GRB 160530A with the Compton Spectrometer and Imager. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/3b8664q5

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lowell, Alexander. “Polarimetric Studies of the Long Duration Gamma-Ray Burst GRB 160530A with the Compton Spectrometer and Imager.” 2017. Thesis, University of California – Berkeley. Accessed January 15, 2021. http://www.escholarship.org/uc/item/3b8664q5.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lowell, Alexander. “Polarimetric Studies of the Long Duration Gamma-Ray Burst GRB 160530A with the Compton Spectrometer and Imager.” 2017. Web. 15 Jan 2021.

Vancouver:

Lowell A. Polarimetric Studies of the Long Duration Gamma-Ray Burst GRB 160530A with the Compton Spectrometer and Imager. [Internet] [Thesis]. University of California – Berkeley; 2017. [cited 2021 Jan 15]. Available from: http://www.escholarship.org/uc/item/3b8664q5.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lowell A. Polarimetric Studies of the Long Duration Gamma-Ray Burst GRB 160530A with the Compton Spectrometer and Imager. [Thesis]. University of California – Berkeley; 2017. Available from: http://www.escholarship.org/uc/item/3b8664q5

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Luleå University of Technology

16. Veal, Daniel. Modeling All-sky Compton Telescopes for Nuclear Astrophysics.

Degree: 2011, Luleå University of Technology

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-56196

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To further efforts in medium energy gamma-ray detector design, the goal of this thesis period was to model a new type of Compton Telescope… (more)

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To further efforts in medium energy gamma-ray detector design, the goal of this thesis period was to model a new type of Compton Telescope for nuclear astrophysics. This involved defining several 3D detector geometry models, simulating far field point source fluxes, and analyzing the results for angular resolution, effective area, and mean area per kilogram of detector. As a prerequisite task, a new Monte Carlo analysis program called MEGAlib was installed at CESR (Center for Study of Space Radiation, Toulouse, France) to complete the modeling and will be available for future simulation work. Abstract The principal investigation was expanding the field of view (FOV) by a factor of 2 to 10 to increase the exposure (observation time multiplied by effective area) and fulfil angular resolution requirements without increasing detector size and mass. A very wide FOV (i.e. 4π) telescope would be exposed to every source at once for longer time, instead of looking at few sources with larger effective areas for shorter observation times. Using MEGAlib, three different detector configurations were modeled. A two-plate classical (similar to COMPTEL), a more compact five-plate stack, and a new six-plate omnidirectional cube geometry. Different detector plate sizes were tested at zenith angles from 0-90° degrees to evaluate off-axis performance. All configurations had similar on-axis angular resolutions (3°) but the new cube configuration had a larger mean effective area exposed to the whole sky, 17 cm² compared to 14 cm² of the next best geometry. However, it also had a mass nearly two times larger, giving the stack geometry the best exposed area to mass ratio. Because the stack geometry had surprisingly good off-axis effective area and was significantly lighter, it is possible that the large FOV concept could be applied to it by opening both its top and bottom to the sky (normally the bottom is shielded and faces the spacecraft) and using the low effective area side regions as feeds for electronics.

Validerat; 20110915 (anonymous)

Subjects/Keywords: Technology; Compton telescopes; gamma-ray detector; MEGAlib; Monte Carlo; Teknik

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APA (6^th Edition):

Veal, D. (2011). Modeling All-sky Compton Telescopes for Nuclear Astrophysics. (Thesis). Luleå University of Technology. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-56196

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Veal, Daniel. “Modeling All-sky Compton Telescopes for Nuclear Astrophysics.” 2011. Thesis, Luleå University of Technology. Accessed January 15, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-56196.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Veal, Daniel. “Modeling All-sky Compton Telescopes for Nuclear Astrophysics.” 2011. Web. 15 Jan 2021.

Vancouver:

Veal D. Modeling All-sky Compton Telescopes for Nuclear Astrophysics. [Internet] [Thesis]. Luleå University of Technology; 2011. [cited 2021 Jan 15]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-56196.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Veal D. Modeling All-sky Compton Telescopes for Nuclear Astrophysics. [Thesis]. Luleå University of Technology; 2011. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-56196

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Michigan

17. LeBlanc, James Walter. A Compton camera for low energy gamma ray imaging in nuclear medicine applications.

Degree: PhD, Nuclear engineering, 1999, University of Michigan

URL: http://hdl.handle.net/2027.42/131926

► C-SPRINT is a prototype electronically-collimated imaging system that has been built using pixellated, low-noise, position-sensitive silicon as the first detector, and a sodium iodide scintillation… (more)

▼ C-SPRINT is a prototype electronically-collimated imaging system that has been built using pixellated, low-noise, position-sensitive silicon as the first detector, and a sodium iodide scintillation detector ring as the second detector. The camera was intended to characterize potential performance gains of Compton cameras in nuclear medicine applications. The system consists of a single 4.5 x 1.5 x 0.03 cm3 silicon pad detector module with 2 keV energy resolution centered at the front face of a 50 cm diameter, 12 cm long NaI detector annulus. Calculations of the Uniform Cramer-Rao lower bound show that a design Compton camera based on our prototype can challenge existing mechanically-collimated systems at low to medium energies (∼140.5 - 400 keV) despite the deleterious effects of Doppler broadening. Measurements with our current system have yielded system sensitivity and spatial resolution estimates using ^99mTc and ¹³¹I isotopes. Results showed an absolute efficiency of 1.8 x 10^-7 for ^99mTc and 1.2 x 10^-6 for ¹³¹I. The ^99mTc value is an order of magnitude lower than predicted because of a combination of worse than expected silicon detector triggering performance, timing resolution issues, and system dead time effects. After correcting for these, efficiency predictions based on Monte Carlo analysis fall within 10% of the measured values. Spatial resolution estimates are also within 10% of analytical predictions. Measured resolution for the ^99mTc point source was 15 min FWHM while in the ¹³¹I case, resolution improved to 8 mm FWHM. Extended source imaging was performed to characterize system performance under more challenging conditions. Images obtained were compared with measurements using a clinically-available mechanically collimated Anger camera. A resolution-variance study was also conducted for both isotopes. The results showed that the C-SPRINT camera performance on a per-detected photon basis was worse than the Anger camera for ^99mTc but was similar for ¹³¹I, as predicted by theory. Potentially large gains in raw system sensitivity of a Compton camera similar in design to C-SPRINT could lead to substantial improvements in noise-equivalent performance of electronically-collimated cameras over mechanical systems, particularly in the energy range above 200 keV. Advisors/Committee Members: Wehe, David K. (advisor).

Subjects/Keywords: Applications; Compton Camera; Energy; Gamma Ray Imaging; Low; Nuclear Medicine

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

LeBlanc, J. W. (1999). A Compton camera for low energy gamma ray imaging in nuclear medicine applications. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/131926

Chicago Manual of Style (16^th Edition):

LeBlanc, James Walter. “A Compton camera for low energy gamma ray imaging in nuclear medicine applications.” 1999. Doctoral Dissertation, University of Michigan. Accessed January 15, 2021. http://hdl.handle.net/2027.42/131926.

MLA Handbook (7^th Edition):

LeBlanc, James Walter. “A Compton camera for low energy gamma ray imaging in nuclear medicine applications.” 1999. Web. 15 Jan 2021.

Vancouver:

LeBlanc JW. A Compton camera for low energy gamma ray imaging in nuclear medicine applications. [Internet] [Doctoral dissertation]. University of Michigan; 1999. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2027.42/131926.

Council of Science Editors:

LeBlanc JW. A Compton camera for low energy gamma ray imaging in nuclear medicine applications. [Doctoral Dissertation]. University of Michigan; 1999. Available from: http://hdl.handle.net/2027.42/131926

Louisiana State University

18. Budden, Brent. Characterization and prototyping of the rotating modulator hard x-ray/gamma-ray telescope.

Degree: PhD, Physical Sciences and Mathematics, 2011, Louisiana State University

URL: etd-04212011-134645 ; https://digitalcommons.lsu.edu/gradschool_dissertations/454

► A hard x-ray/gamma-ray telescope with high sensitivity and wide field of view would be capable of performing an all-sky census of black holes over a… (more)

▼ A hard x-ray/gamma-ray telescope with high sensitivity and wide field of view would be capable of performing an all-sky census of black holes over a wide range of obscuration and accretion rates. As an example, NASA's Black Hole Finder Probe mission was designed to provide a 5-sigma flux sensitivity in a 1-year observation of ~0.02 mCrab in the 10 - 150 keV energy range and 0.5 mCrab in the 150 - 600 keV energy range with 3 - 5 minutes of arc angular resolution. These are significantly higher sensitivity and resolution goals than those of current instruments. The design focus on sensitivity would make the instrument equally suitable for national security applications in the detection of weak shielded illicit radioactive materials at large distances (100 m - 1 km). X-ray and gamma-ray imaging designs for astrophysics and security applications typically utilize a coded aperture imaging technique. The spatial resolution necessary, however, coupled with the specification of high sensitivity, requires a large number of readout channels (resulting in high cost and complexity) and limits the use of this technique to relatively low energies. As an alternative approach, an investigation is made here of the rotating modulator (RM), which uses primarily temporal modulation to record an object scene. The RM consists of a mask of opaque slats that rotates above an array of detectors. Time histories of counts recorded by each detector are used to reconstruct the object scene distribution. Since a full study of RM characterization and capabilities has not been performed prior to this work, a comprehensive analytic system response is presented, which accounts for realistic modulation geometries. The RM imaging characteristics and sensitivity are detailed, including a comparison to more common hard x-ray imaging modalities. A novel image reconstruction algorithm is developed to provide noise-compensation, super-resolution, and high fidelity. A laboratory prototype RM and its measurement results are presented. As a pathfinder mission to an eventual astrophysics campaign, a one-day high-altitude balloon-borne RM is also described, including expected performance and imaging results. Finally, RM designs suitable for next-generation astrophysics and security applications are presented, and improvements to the RM technique are suggested.

Subjects/Keywords: gamma ray; x-ray; rotating modulation; imaging

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APA (6^th Edition):

Budden, B. (2011). Characterization and prototyping of the rotating modulator hard x-ray/gamma-ray telescope. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-04212011-134645 ; https://digitalcommons.lsu.edu/gradschool_dissertations/454

Chicago Manual of Style (16^th Edition):

Budden, Brent. “Characterization and prototyping of the rotating modulator hard x-ray/gamma-ray telescope.” 2011. Doctoral Dissertation, Louisiana State University. Accessed January 15, 2021. etd-04212011-134645 ; https://digitalcommons.lsu.edu/gradschool_dissertations/454.

MLA Handbook (7^th Edition):

Budden, Brent. “Characterization and prototyping of the rotating modulator hard x-ray/gamma-ray telescope.” 2011. Web. 15 Jan 2021.

Vancouver:

Budden B. Characterization and prototyping of the rotating modulator hard x-ray/gamma-ray telescope. [Internet] [Doctoral dissertation]. Louisiana State University; 2011. [cited 2021 Jan 15]. Available from: etd-04212011-134645 ; https://digitalcommons.lsu.edu/gradschool_dissertations/454.

Council of Science Editors:

Budden B. Characterization and prototyping of the rotating modulator hard x-ray/gamma-ray telescope. [Doctoral Dissertation]. Louisiana State University; 2011. Available from: etd-04212011-134645 ; https://digitalcommons.lsu.edu/gradschool_dissertations/454

19. Savva, Marilia. Ανάπτυξη και εφαρμογή τεχνικών προσδιορισμού πολύ χαμηλών συγκεντρώσεων ραδιενεργών ιχνοστοιχείων σε δείγματα περιβαλλοντικής σημασίας.

Degree: 2017, National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ)

URL: http://hdl.handle.net/10442/hedi/42279

► The aim of this PhD Thesis was the determination of very low concentrations of natural and artificial radioactive isotopes in environmental samples by means of… (more)

▼ The aim of this PhD Thesis was the determination of very low concentrations of natural and artificial radioactive isotopes in environmental samples by means of gamma-spectroscopy techniques. Natural and artificial radioactive isotopes of low or higher specific activity are contained and can be detected in any environmental sample. Even when their specific activity is low, leading to negligible radiobiological significance, their detection is of interest in various applications, such as their use as tracers for environmental processes. In addition, improving the levels of detection of an isotope using a γ-spectroscopic apparatus, may allow the detection of the isotope in smaller volume samples without significant compromise on the accuracy of the measurement, which has obvious consequences in the design of the sampling. Since the background of a γ-spectroscopic apparatus is a factor determining the ability to detect low levels of radioactivity in a sample, its reduction is always highly desirable.In the framework of the Thesis the installation, study and use of the new Compton Suppression system (CSS), which was installed on the XtRa detector of the N.E.D. - N.T.U.A was carried out, aiming the reduction the continuous background of the detector and the improvement of the detection limits of the XtRa - CSS apparatus. The electronic set-up of the apparatus allows for the simultaneous collection of two spectra with a suppressed or not (unsuppressed) continuous background. In the framework of the study, a series of response factors were used, as referred in literature, through which the effect of various phenomena observed in the detection of photons by the Compton Suppression system was identified, and should be taken into account both during the calibration of the device, and during routine analyzes. As a result of this study, the optimal conditions for the detection of each isotope are proposed. The device was then calibrated experimentally but also using Monte Carlo simulation techniques for a series of source-to-detector geometries. For this purpose, it was necessary to modify the PENELOPE simulation code used in the N.E.D. - N.T.U.A in order to take into account both the true coincidence phenomenon during spectrum collection and to simulate a Compton Suppression system consisting of two independent detectors (primary detector and secondary detector or active shield) that communicate with each other.One of the main objectives of the Thesis was the detection of radioactive isotopes found at very low concentrations in environmental samples. For this purpose appropriate sampling techniques for atmospheric aerosols and liquid atmospheric precipitations and sample preparation were developed and a large number of samples were analyzed, mainly (a) contaminated samples due to the nuclear accidents in Chernobyl and Fukushima, (b) atmospheric aerosol and precipitation samples. From these analyzes it was possible to detect 241Am from the Chernobyl accident and a strong correlation with the 137Cs concentration was found. In…

Subjects/Keywords: γ-Φασματοσκοπία; Σύστημα Compton Suppression; Gamma-spectrometry; Compton Suppression System

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Savva, M. (2017). Ανάπτυξη και εφαρμογή τεχνικών προσδιορισμού πολύ χαμηλών συγκεντρώσεων ραδιενεργών ιχνοστοιχείων σε δείγματα περιβαλλοντικής σημασίας. (Thesis). National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ). Retrieved from http://hdl.handle.net/10442/hedi/42279

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Savva, Marilia. “Ανάπτυξη και εφαρμογή τεχνικών προσδιορισμού πολύ χαμηλών συγκεντρώσεων ραδιενεργών ιχνοστοιχείων σε δείγματα περιβαλλοντικής σημασίας.” 2017. Thesis, National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ). Accessed January 15, 2021. http://hdl.handle.net/10442/hedi/42279.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Savva, Marilia. “Ανάπτυξη και εφαρμογή τεχνικών προσδιορισμού πολύ χαμηλών συγκεντρώσεων ραδιενεργών ιχνοστοιχείων σε δείγματα περιβαλλοντικής σημασίας.” 2017. Web. 15 Jan 2021.

Vancouver:

Savva M. Ανάπτυξη και εφαρμογή τεχνικών προσδιορισμού πολύ χαμηλών συγκεντρώσεων ραδιενεργών ιχνοστοιχείων σε δείγματα περιβαλλοντικής σημασίας. [Internet] [Thesis]. National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ); 2017. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10442/hedi/42279.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Savva M. Ανάπτυξη και εφαρμογή τεχνικών προσδιορισμού πολύ χαμηλών συγκεντρώσεων ραδιενεργών ιχνοστοιχείων σε δείγματα περιβαλλοντικής σημασίας. [Thesis]. National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ); 2017. Available from: http://hdl.handle.net/10442/hedi/42279

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

20. Aucott, Timothy John. Gamma-Ray Background Variability in Mobile Detectors.

Degree: Nuclear Engineering, 2014, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/2ph593s2

► Gamma-ray background radiation significantly reduces detection sensitivity when searching for radioactive sources in the field, such as in wide-area searches for homeland security applications. Mobile… (more)

▼ Gamma-ray background radiation significantly reduces detection sensitivity when searching for radioactive sources in the field, such as in wide-area searches for homeland security applications. Mobile detector systems in particular must contend with a variable background that is not necessarily known or even measurable a priori. This work will present measurements of the spatial and temporal variability of the background, with the goal of merging gamma-ray detection, spectroscopy, and imaging with contextual information – a "nuclear street view" of the ubiquitous background radiation.The gamma-ray background originates from a variety of sources, both natural and anthropogenic. The dominant sources in the field are the primordial isotopes potassium-40, uranium-238, and thorium-232, as well as their decay daughters. In addition to the natural background, many artificially-created isotopes are used for industrial or medical purposes, and contamination from fission products can be found in many environments. Regardless of origin, these backgrounds will reduce detection sensitivity by adding both statistical as well as systematic uncertainty. In particular, large detector arrays will be limited by the systematic uncertainty in the background and will suffer from a high rate of false alarms.The goal of this work is to provide a comprehensive characterization of the gamma-ray background and its variability in order to improve detection sensitivity and evaluate the performance of mobile detectors in the field. Large quantities of data are measured in order to study their performance at very low false alarm rates. Two different approaches, spectroscopy and imaging, are compared in a controlled study in the presence of this measured background. Furthermore, there is additional information that can be gained by correlating the gamma-ray data with contextual data streams (such as cameras and global positioning systems) in order to reduce the variability in the background.This is accomplished by making many hours of background measurements with a truck-mounted system, which utilizes high-purity germanium detectors for spectroscopy and sodium iodide detectors for coded aperture imaging. This system also utilizes various peripheral sensors, such as panoramic cameras, laser ranging systems, global positioning systems, and a weather station to provide context for the gamma-ray data. About three hundred hours of data were taken in the San Francisco Bay Area, covering a wide variety of environments that might be encountered in operational scenarios. These measurements were used in a source injection study to evaluate the sensitivity of different algorithms (imaging and spectroscopy) and hardware (sodium iodide and high-purity germanium detectors).These measurements confirm that background distributions in large, mobile detector systems are dominated by systematic, not statistical variations, and both spectroscopy and imaging were found to substantially reduce this variability. Spectroscopy performed better than the coded aperture for…

Subjects/Keywords: Nuclear engineering; Nuclear physics; Background radiation; Gamma-ray detection; Gamma-ray imaging; Gamma-ray spectroscopy

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APA (6^th Edition):

Aucott, T. J. (2014). Gamma-Ray Background Variability in Mobile Detectors. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/2ph593s2

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Aucott, Timothy John. “Gamma-Ray Background Variability in Mobile Detectors.” 2014. Thesis, University of California – Berkeley. Accessed January 15, 2021. http://www.escholarship.org/uc/item/2ph593s2.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Aucott, Timothy John. “Gamma-Ray Background Variability in Mobile Detectors.” 2014. Web. 15 Jan 2021.

Vancouver:

Aucott TJ. Gamma-Ray Background Variability in Mobile Detectors. [Internet] [Thesis]. University of California – Berkeley; 2014. [cited 2021 Jan 15]. Available from: http://www.escholarship.org/uc/item/2ph593s2.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Aucott TJ. Gamma-Ray Background Variability in Mobile Detectors. [Thesis]. University of California – Berkeley; 2014. Available from: http://www.escholarship.org/uc/item/2ph593s2

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Texas – Austin

21. Schreiber, Samuel Stuart. Identification of the radionuclides in spent nuclear fuel that may be detected by Compton suppression and gamma-gamma coincidence methods.

Degree: MSin Engineering, Mechanical Engineering, 2011, University of Texas – Austin

URL: http://hdl.handle.net/2152/ETD-UT-2011-05-2701

► The nuclides present in spent nuclear fuel are categorized according to their capacity for detection by Compton suppression or gamma-gamma coincidence methods. The fifty nuclides… (more)

Subjects/Keywords: Spent nuclear fuel; Compton suppression; Gamma-gamma coincidence; Multi-isotope process monitor; MIP; nonprolNferation; Gamma ray signatures

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APA (6^th Edition):

Schreiber, S. S. (2011). Identification of the radionuclides in spent nuclear fuel that may be detected by Compton suppression and gamma-gamma coincidence methods. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/ETD-UT-2011-05-2701

Chicago Manual of Style (16^th Edition):

Schreiber, Samuel Stuart. “Identification of the radionuclides in spent nuclear fuel that may be detected by Compton suppression and gamma-gamma coincidence methods.” 2011. Masters Thesis, University of Texas – Austin. Accessed January 15, 2021. http://hdl.handle.net/2152/ETD-UT-2011-05-2701.

MLA Handbook (7^th Edition):

Schreiber, Samuel Stuart. “Identification of the radionuclides in spent nuclear fuel that may be detected by Compton suppression and gamma-gamma coincidence methods.” 2011. Web. 15 Jan 2021.

Vancouver:

Schreiber SS. Identification of the radionuclides in spent nuclear fuel that may be detected by Compton suppression and gamma-gamma coincidence methods. [Internet] [Masters thesis]. University of Texas – Austin; 2011. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2152/ETD-UT-2011-05-2701.

Council of Science Editors:

Schreiber SS. Identification of the radionuclides in spent nuclear fuel that may be detected by Compton suppression and gamma-gamma coincidence methods. [Masters Thesis]. University of Texas – Austin; 2011. Available from: http://hdl.handle.net/2152/ETD-UT-2011-05-2701

22. Amoyal, Guillaume. Développement d'un imageur gamma hybride pour les applications de l'industrie nucléaire : Development of a hybrid gamma imager for nuclear industry applications.

Degree: Docteur es, Physique, 2019, Normandie

URL: http://www.theses.fr/2019NORMC216

►

L'imagerie gamma est une technique qui permet la localisation spatiale de sources radioactives. Les différentes applications de cette technique couvrent les phases de démantèlement des… (more)

▼

L'imagerie gamma est une technique qui permet la localisation spatiale de sources radioactives. Les différentes applications de cette technique couvrent les phases de démantèlement des installations nucléaires ou de gestion des déchets nucléaires, mais aussi la radioprotection ou la sécurité intérieure. L'utilisation de caméras gamma permet de réduire la dose reçue par les opérateurs, et, par conséquent, de respecter le principe ALARA. Il existe deux techniques d’imagerie permettant la localisation de radioéléments émetteurs gamma : l’imagerie à masque codé et l’imagerie Compton. L’imagerie à masque codé utilise la modulation spatiale du flux de photons gamma incidents par collimateur multi-trous placé entre la source et le détecteur. Elle présente l’avantage d’être extrêmement performante pour des émetteurs gamma « basses énergies », aussi bien en matière de sensibilité, qu’en matière de résolution angulaire. L'imagerie Compton, quant à elle, repose sur l’utilisation de la mécanique de diffusion Compton. L'énergie déposée pendant le processus de diffusion déterminera l'angle de diffusion, et les positions des interactions détermineront la direction des rayons gamma entrants. La position de la source radioactive peut ainsi être limitée à un cône. Si plusieurs cônes sont utilisés, alors la position où le plus grand nombre de cônes se chevauchent correspond à la position de la source radioactive. Une des limitations de cette technique concerne la localisation des émetteurs gamma « basses énergies », pour lesquels la résolution angulaire est fortement dégradée allant jusqu’à l’impossibilité complète de trouver la position. L’objectif de ces travaux est de développer un prototype d’imageur hybride associant les techniques d’imagerie à masque codé et d’imagerie Compton, afin de tirer profit des avantages de chacun des types d’imagerie. Les différents travaux menés, autour du détecteur pixellisé Timepix3, mais aussi en matière de développement d’algorithmes mathématiques, ont permis de proposer deux prototypes d’imageurs hybrides. Les résultats obtenus à l’issue de ces travaux de recherche ont permis de valider expérimentalement les performances d’un des prototypes d’imageurs et d’illustrer l’intérêt d’un système hybride.

Gamma imaging is a technique that allows the spatial localization of radioactive sources. The various applications of this technique cover decommissioning phases of nuclear facilities, nuclear waste management applications, but also radiation protection or Homeland Security. Using gamma camera reduces the dose received by operators and consequently contributes to the respect of the ALARA principle. There are two imaging techniques for the localization of gamma ray emitters: coded aperture imaging and Compton imaging. Coded aperture imaging relies on the spatial modulation of the incident gamma-ray flux by a multi-hole collimator placed between the detector and the radioactive source. It has the advantage of being extremely efficient for « low energy » gamma-ray emitters in terms of sensitivity and…

Advisors/Committee Members: Angélique, Jean-Claude (thesis director).

Subjects/Keywords: Imagerie gamma; Imagerie à masque codé; Imagerie Compton; Détecteur hybride pixellisé; Timepix3; Gamma Imaging; Coded aperture imaging; Compton Imaging; Hybrid pixel detector; Timepix3; CdTe; Si

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Amoyal, G. (2019). Développement d'un imageur gamma hybride pour les applications de l'industrie nucléaire : Development of a hybrid gamma imager for nuclear industry applications. (Doctoral Dissertation). Normandie. Retrieved from http://www.theses.fr/2019NORMC216

Chicago Manual of Style (16^th Edition):

Amoyal, Guillaume. “Développement d'un imageur gamma hybride pour les applications de l'industrie nucléaire : Development of a hybrid gamma imager for nuclear industry applications.” 2019. Doctoral Dissertation, Normandie. Accessed January 15, 2021. http://www.theses.fr/2019NORMC216.

MLA Handbook (7^th Edition):

Amoyal, Guillaume. “Développement d'un imageur gamma hybride pour les applications de l'industrie nucléaire : Development of a hybrid gamma imager for nuclear industry applications.” 2019. Web. 15 Jan 2021.

Vancouver:

Amoyal G. Développement d'un imageur gamma hybride pour les applications de l'industrie nucléaire : Development of a hybrid gamma imager for nuclear industry applications. [Internet] [Doctoral dissertation]. Normandie; 2019. [cited 2021 Jan 15]. Available from: http://www.theses.fr/2019NORMC216.

Council of Science Editors:

Amoyal G. Développement d'un imageur gamma hybride pour les applications de l'industrie nucléaire : Development of a hybrid gamma imager for nuclear industry applications. [Doctoral Dissertation]. Normandie; 2019. Available from: http://www.theses.fr/2019NORMC216

University of Michigan

23. Lehner, Carolyn E. 4-pi Compton imaging using a single three-dimensional position sensitive cadmium zinc telluride detector.

Degree: PhD, Pure Sciences, 2004, University of Michigan

URL: http://hdl.handle.net/2027.42/124474

► Compton imagers are promising tools for nuclear non-proliferation, astronomy, and medical applications, but typically have a limited angular field-of-view and poor efficiency resulting from requiring… (more)

▼ Compton imagers are promising tools for nuclear non-proliferation, astronomy, and medical applications, but typically have a limited angular field-of-view and poor efficiency resulting from requiring that gamma rays interact in two or more detectors. This work is the first successful demonstration of Compton imaging with a 4pi field-of-view using a single CdZnTe detector. There are several challenges involved in using a single detector for Compton imaging. First, the energies and three-dimensional positions of gamma-ray interactions must be determined. The detector used in this work has a pixellated anode to provide position sensitivity in two dimensions, and the third dimension is obtained from signal timing. Then, the sequence of interactions in the detector must be determined. Two such methods are attempted and compared. Finally, image reconstruction must be performed. Both simple backprojection and maximum likelihood reconstruction algorithms are demonstrated. Several factors that can degrade the performance of the 4pi imager are examined. Physical processes, such as Doppler broadening, coherent scatter, and pair production, affect the resolution of the imager. Doppler broadening has the most significant effect, limiting the resolution to at least several degrees in CdZnTe. The anode thresholds in the detector and the dynamic range of the ASICs limit the observable events in the detector, contributing to a major loss in efficiency for both low- and high-energy gamma rays. Also, the size of the anode pixels determines both the amount of charge sharing and fraction of sequences that involve more than one interaction under one pixel. Finally, the sequence-ordering algorithm creates artifacts in the image and degrades resolution. Intrinsic imaging efficiency is defined as the fraction of incident gamma rays in which the total energy was deposited in two or more observed events, no pair production occurred, and the determined sequence order is kinematically possible. With a detector volume of only 2.25 cm³ the measured intrinsic imaging efficiency of the imager is 1.86% at 662 keV, an improvement by three orders of magnitude from the previous design. Using a new weighting method for maximum likelihood reconstruction yields a measured imaging resolution of 17° full-width at half-maximum at the same energy. Two point sources separated by 18° can be resolved, confirming the measured resolution. Imaging of high-energy (2.6 MeV) and extended sources is also demonstrated. Advisors/Committee Members: He, Zhong (advisor).

Subjects/Keywords: Cadmium Zinc Telluride; Compton Imaging; Detector; Dimensional; Gamma-ray Imaging; Pi; Position; Sensitive; Single; Three; Using

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lehner, C. E. (2004). 4-pi Compton imaging using a single three-dimensional position sensitive cadmium zinc telluride detector. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/124474

Chicago Manual of Style (16^th Edition):

Lehner, Carolyn E. “4-pi Compton imaging using a single three-dimensional position sensitive cadmium zinc telluride detector.” 2004. Doctoral Dissertation, University of Michigan. Accessed January 15, 2021. http://hdl.handle.net/2027.42/124474.

MLA Handbook (7^th Edition):

Lehner, Carolyn E. “4-pi Compton imaging using a single three-dimensional position sensitive cadmium zinc telluride detector.” 2004. Web. 15 Jan 2021.

Vancouver:

Lehner CE. 4-pi Compton imaging using a single three-dimensional position sensitive cadmium zinc telluride detector. [Internet] [Doctoral dissertation]. University of Michigan; 2004. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2027.42/124474.

Council of Science Editors:

Lehner CE. 4-pi Compton imaging using a single three-dimensional position sensitive cadmium zinc telluride detector. [Doctoral Dissertation]. University of Michigan; 2004. Available from: http://hdl.handle.net/2027.42/124474

24. Richard, Marie-Hélène. Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie.

Degree: Docteur es, Physique, 2012, Université Claude Bernard – Lyon I

URL: http://www.theses.fr/2012LYO10124

►

L'hadronthérapie est une technique innovante de radiothérapie par ions carbone ou protons visant à améliorer les traitements actuels. La précision balistique accrue renforce la nécessité… (more)

▼

L'hadronthérapie est une technique innovante de radiothérapie par ions carbone ou protons visant à améliorer les traitements actuels. La précision balistique accrue renforce la nécessité d'un contrôle du dépôt de dose, si possible en temps réel. Une manière de réaliser ce contrôle est de détecter avec une caméra Compton le gamma prompt émis lors des fragmentations nucléaires pendant l'irradiation du patient. Dans un premier temps, la géométrie de deux types de caméra Compton (double diffusion puis simple diffusion) a été optimisée par simulation Monte Carlo. Cette optimisation a été réalisée en étudiant la réponse des caméras à une source ponctuelle de photons avec un spectre en énergie réaliste. La réponse de la caméra optimisée à l'irradiation d'un fantôme d'eau par un faisceau d'ions carbone ou de protons a ensuite été simulée. Ces simulations ont tout d'abord été confrontées à des mesures effectuées avec un prototype de taille réduite. Ces mesures ont ensuite été utilisées pour évaluer les taux de comptage dans les détecteurs attendus en conditions cliniques. Dans la configuration actuelle de la caméra, ces taux sont élevés et les phénomènes d'empilement risquent d'être problématiques. Enfin, il est démontré que le dispositif étudié est sensible à un déplacement du pic de Bragg de plus ou moins 5 mm malgré les problèmes de coïncidences fortuites et malgré le bruit introduit par l'algorithme de reconstruction utilisé.

Ion beam therapy is an innovative radiotherapy technique using mainly carbon ion and proton irradiations. Its aim is to improve the current treatment modalities. Because of the sharpness of the dose distributions, a control of the dose if possible in real time is highly desirable. A possibility is to detect the prompt gamma rays emitted subsequently to the nuclear fragmentations occurring during the treatment of the patient. In a first time two different Compton cameras (double and single scattering) have been optimised by means of Monte Carlo simulations. The response of the camera to a photon point source with a realistic energy spectrum was studied. Then, the response of the camera to the irradiation of a water phantom by a proton beam was simulated. It was first compared with measurement performed with small-size detectors. Then, using the previous measurements, we evaluated the counting rates expected in clinical conditions. In the current set-up of the camera, these counting rates are pretty high. Pile up and random coincidences will be problematic. Finally we demonstrate that the detection system is capable to detect a longitudinal shift in the Bragg peak of +or- 5 mm, even with the current reconstruction algorithm.

Advisors/Committee Members: Ray, Cédric (thesis director), Létang, Jean-Michel (thesis director).

Subjects/Keywords: Hadronthérapie; Geant4; Monte Carlo; Gamma prompts; Ion beam therapy; Geant4; Monte Carlo; Compton camera; Prompt gamma ray; 537.535

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Richard, M. (2012). Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie. (Doctoral Dissertation). Université Claude Bernard – Lyon I. Retrieved from http://www.theses.fr/2012LYO10124

Chicago Manual of Style (16^th Edition):

Richard, Marie-Hélène. “Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie.” 2012. Doctoral Dissertation, Université Claude Bernard – Lyon I. Accessed January 15, 2021. http://www.theses.fr/2012LYO10124.

MLA Handbook (7^th Edition):

Richard, Marie-Hélène. “Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie.” 2012. Web. 15 Jan 2021.

Vancouver:

Richard M. Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie. [Internet] [Doctoral dissertation]. Université Claude Bernard – Lyon I; 2012. [cited 2021 Jan 15]. Available from: http://www.theses.fr/2012LYO10124.

Council of Science Editors:

Richard M. Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie. [Doctoral Dissertation]. Université Claude Bernard – Lyon I; 2012. Available from: http://www.theses.fr/2012LYO10124

University of Michigan

25. Shy, Daniel. Super-MeV Compton Imaging and 3D Gamma-Ray Imaging Using Pixelated CdZnTe.

Degree: PhD, Nuclear Science, 2020, University of Michigan

URL: http://hdl.handle.net/2027.42/155099

► The dissertation presents work in gamma-ray imaging in the MeV range, 3D Compton imaging, and time encoded imaging. The first thrust in high energy gamma-ray… (more)

▼ The dissertation presents work in gamma-ray imaging in the MeV range, 3D Compton imaging, and time encoded imaging. The first thrust in high energy gamma-ray imaging begins with analyzing the artifacts produced. These factors include the increase in pair-production events, incorrect event sequencing, and charge sharing due to the larger electron clouds. They all result in shift-variant artifacts that degrade the signal-to-noise ratio as well as create artifacts that might be mistaken for a hot spot. The degradation from artifacts is discussed and possible mitigation techniques are presented to allow for recovery of the Compton image. One of the presented mitigation techniques proposes a new sequencing algorithm for 3-or-more interaction events, called FIL-MSD. Missequencing presents one of the more dominant artifacts and by fixing the first interaction to be the largest deposited energy, the sequencing efficiency has increased by 20% in simulated data. Experimental results show an almost twofold increase in the signal to noise ratio (SNR) for simple backprojection images of a 22Na (1.7 MeV) source. The image resolution using filtered backprojection (FBP) was improved on by developing an analytical point spread function model for high energy 3-interaction events. Previous models did not account for missequencing effects in the model. Adding these effects into the model improved the resolution of the image, but at a cost of increased artifact production. In addition, the Wiener filter was formalized for spherical harmonics, which could be used for any number of interaction given an appropriate point spread function model. Next, demonstration of a 3D Compton imaging system is accomplished via sensor fusion of a foot-mounted odometer and a CdZnTe detector. A comparison between 3D Compton imaging and inverse-square image-reconstruction algorithms for certain measurement conditions is presented. The experiments demonstrate the advantage of 3D Compton imaging over traditional localization techniques in those scenarios. Improvements in time encoded imaging (TEI) were also made with advancements in the reconstruction algorithms and was done so in three thrusts: use of subpixel sensing, depth of interaction correction, and 3D imaging of extended sources. Complex 3D objects was accomplished via the use of magnification-parallax effects which allowed for the estimation of a source in distance away from the detector. Both the 3D Compton imaging and TEI techniques were explored at the Idaho National Laboratory. Advisors/Committee Members: He, Zhong (committee member), Aidala, Christine A (committee member), Fessler, Jeffrey A (committee member), Jovanovic, Igor (committee member), Thompson, Scott J. (committee member).

Subjects/Keywords: Gamma-ray Imaging; 3D Gamma-ray Imaging; MeV Gamma rays; Nuclear Engineering and Radiological Sciences; Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Shy, D. (2020). Super-MeV Compton Imaging and 3D Gamma-Ray Imaging Using Pixelated CdZnTe. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/155099

Chicago Manual of Style (16^th Edition):

Shy, Daniel. “Super-MeV Compton Imaging and 3D Gamma-Ray Imaging Using Pixelated CdZnTe.” 2020. Doctoral Dissertation, University of Michigan. Accessed January 15, 2021. http://hdl.handle.net/2027.42/155099.

MLA Handbook (7^th Edition):

Shy, Daniel. “Super-MeV Compton Imaging and 3D Gamma-Ray Imaging Using Pixelated CdZnTe.” 2020. Web. 15 Jan 2021.

Vancouver:

Shy D. Super-MeV Compton Imaging and 3D Gamma-Ray Imaging Using Pixelated CdZnTe. [Internet] [Doctoral dissertation]. University of Michigan; 2020. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2027.42/155099.

Council of Science Editors:

Shy D. Super-MeV Compton Imaging and 3D Gamma-Ray Imaging Using Pixelated CdZnTe. [Doctoral Dissertation]. University of Michigan; 2020. Available from: http://hdl.handle.net/2027.42/155099

Duke University

26. Sun, Changchun. Characterizations and Diagnostics of Compton Light Source .

Degree: 2009, Duke University

URL: http://hdl.handle.net/10161/1579

► The High Intensity Gamma-ray Source (HIGS) at Duke University is a world class Compton light source facility. At the HIGS, a Free-Electron Laser (FEL)… (more)

▼ The High Intensity Gamma-ray Source (HIGS) at Duke University is a world class Compton light source facility. At the HIGS, a Free-Electron Laser (FEL) beam is Compton scattered with an electron beam in the Duke storage ring to produce an intense, highly polarized, and nearly monoenergetic gamma-ray beam with a tunable energy from about 1 MeV to 100 MeV. This unique gamma-ray beam has been used in a wide range of basic and application research fields from nuclear physics to astrophysics, from medical research to homeland security and industrial applications. The capability of accurately predicting the spatial, spectral and temporal characteristics of a Compton gamma-ray beam is crucial for the optimization of the operation of a Compton light source as well as for the applications utilizing the Compton beam. In this dissertation, we have successfully developed two approaches, an analytical calculation method and a Monte Carlo simulation technique, to study the Compton scattering process. Using these two approaches, we have characterized the HIGS beams with varying electron beam parameters as well as different collimation conditions. Based upon the Monte Carlo simulation, an end-to-end spectrum reconstruction method has been developed to analyze the measured energy spectrum of a HIGS beam. With this end-to-end method, the underlying energy distribution of the HIGS beam can be uncovered with a high degree of accuracy using its measured spectrum. To measure the transverse profile of the HIGS beam, we have developed a CCD based gamma-ray beam imaging system with a sub-mm spatial resolution and a high contrast sensitivity. This imaging system has been routinely used to align experimental apparatus with the HIGS beam for nuclear physics research. To determine the energy distribution of the HIGS beam, it is important to know the energy distribution of the electron beam used in the collision. The electron beam energy and energy spread can be measured using the Compton scattering technique. In order to use this technique, we have developed a new fitting model directly based upon the Compton scattering cross section while taking into account the electron-beam emittance and gamma-beam collimation effects. With this model, we have successfully carried out a precise energy measurement of the electron beam in the Duke storage ring. Alternatively, the electron beam energy can be measured using the Resonant Spin Depolarization technique, which requires a polarized electron beam. The radiative polarization of an electron beam in the Duke storage ring has been studied as part of this dissertation program. From electron-beam lifetime measurements, the equilibrium degree of polarization of the electron beam has been successfully determined. With the polarized electron beam, we will be able to apply the Resonant Spin Depolarization technique to accurately determine the electron beam energy. This on-going research is of great importance to our continued development of the HIGS facility. Advisors/Committee Members: Wu, Ying K (advisor).

Subjects/Keywords: Physics, Radiation; Physics, Elementary Particles and High Energy; Compton scattering; Electron Polarization; Gamma; ray imaging; Synchrotron radiation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sun, C. (2009). Characterizations and Diagnostics of Compton Light Source . (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/1579

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sun, Changchun. “Characterizations and Diagnostics of Compton Light Source .” 2009. Thesis, Duke University. Accessed January 15, 2021. http://hdl.handle.net/10161/1579.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sun, Changchun. “Characterizations and Diagnostics of Compton Light Source .” 2009. Web. 15 Jan 2021.

Vancouver:

Sun C. Characterizations and Diagnostics of Compton Light Source . [Internet] [Thesis]. Duke University; 2009. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/10161/1579.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sun C. Characterizations and Diagnostics of Compton Light Source . [Thesis]. Duke University; 2009. Available from: http://hdl.handle.net/10161/1579

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

27. Feng, Yuemeng. Modeling and regularization in tomographic reconstruction for Compton camera imaging : Modélisation et régularisation en reconstruction tomographique pour l'imagerie par caméra Compton.

Degree: Docteur es, STIC Santé, 2019, Lyon

URL: http://www.theses.fr/2019LYSEI084

►

La caméra Compton est un dispositif d'imagerie gamma pour la tomographie par émission monophotonique (TEMP). Les améliorations qu’elle pourrait apporter aux applications médicales font l’objet… (more)

▼

La caméra Compton est un dispositif d'imagerie gamma pour la tomographie par émission monophotonique (TEMP). Les améliorations qu’elle pourrait apporter aux applications médicales font l’objet de nombreuses études. Elles dépendent à la fois des développements instrumentaux et des techniques de traitement des données, dont la reconstruction tomographique est une étape-clé. Le but de cette thèse est d’améliorer les performances des algorithmes de reconstruction itératifs calculant le maximum de vraisemblance en mode liste (LM-MLEM). En imagerie avec une caméra Compton, le modèle d’acquisition est basé sur l’intégrale de l’intensité de la source sur des projections coniques. La modélisation des incertitudes de mesure influence fortement le résultat de LM-MLEM. L’une des contributions de cette étude est de montrer qu’un modèle plus précis de l’élargissement Doppler, validé avec la simulation Monte-Carlo, conduit à des images plus quantitatives. Une autre contribution est une méthode de régularisation par contrôle de la variation totale (TV) pour des données distribuées selon une loi de Poisson. La régularisation TV permet d’améliorer fortement la qualité des images pour les acquisitions à faible statistique rencontrées dans les applications de ce type d’imagerie. Nous avons également étudié l’apport de la déconvolution avec la fonction d’étalement du point dans le domaine de l’image, en conjonction avec la régularisation. Cette approche est utilisée pour corriger les effets physiques trop difficile à modéliser dans la fonction de transfert. Toutes les méthodes ont été validées avec des simulations Monte-Carlo.

The Compton camera is an imaging device for SPECT (Single Particle Emission Computed Tomography) of increased sensitivity compared to the Anger camera as it does not require mechanical collimation. The goal of this thesis is to evaluate the improvements that Compton camera may bring for nuclear medicine applications, depending both on technological developments and data processing techniques, among which the tomographic reconstruction is currently a bottleneck. In Compton camera imaging, the acquisition model is based on the integral of the intensity of the source on conical shapes. Modeling the measurement uncertainties in the system matrix can strongly influence the result of the list mode MLEM iterative reconstruction algorithm. One of the contributions of this study is a more precise model validated by Monte Carlo simulation. Another contribution concerns regularization methods. We developed a total variation denoising algorithm for Poisson distributed data that we introduced in the MLEM reconstruction as a regularization step, which allows to improve the image quality in low-counts experiments. A total variation regularized EM reconstruction with PSF deconvolution in the image space is also proposed for ameliorating the conditioning of the inverse problem and restoring the resolution of reconstructed images. All the proposed methods were validated on Monte Carlo simulation.

Advisors/Committee Members: Maxim, Voichiţa Theodora (thesis director), Sarrut, David (thesis director).

Subjects/Keywords: Imagerie; Caméra Compton; Imagerie Compton; Reconstruction tomographique; Imagerie gamma; Tomographie par émission monophotonique - TEMP; Simulation Monte Carlo; Qualité image; Déconvolution; Restauration d'images; Hadronthérapie; Thérapie par hadron; Modélisation; Imaging; Compton camera; Compton imaging; Tomographic Reconstruction; Gamma camera; Single Particle Emission Computed Tomography - SPECT; Monte Carlo Simulation; Imaging quality; Deconvolution; Image restoration; Hadrontherapy; Hadrontherapy; Modelisation; 616.075 707 2

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Feng, Y. (2019). Modeling and regularization in tomographic reconstruction for Compton camera imaging : Modélisation et régularisation en reconstruction tomographique pour l'imagerie par caméra Compton. (Doctoral Dissertation). Lyon. Retrieved from http://www.theses.fr/2019LYSEI084

Chicago Manual of Style (16^th Edition):

Feng, Yuemeng. “Modeling and regularization in tomographic reconstruction for Compton camera imaging : Modélisation et régularisation en reconstruction tomographique pour l'imagerie par caméra Compton.” 2019. Doctoral Dissertation, Lyon. Accessed January 15, 2021. http://www.theses.fr/2019LYSEI084.

MLA Handbook (7^th Edition):

Feng, Yuemeng. “Modeling and regularization in tomographic reconstruction for Compton camera imaging : Modélisation et régularisation en reconstruction tomographique pour l'imagerie par caméra Compton.” 2019. Web. 15 Jan 2021.

Vancouver:

Feng Y. Modeling and regularization in tomographic reconstruction for Compton camera imaging : Modélisation et régularisation en reconstruction tomographique pour l'imagerie par caméra Compton. [Internet] [Doctoral dissertation]. Lyon; 2019. [cited 2021 Jan 15]. Available from: http://www.theses.fr/2019LYSEI084.

Council of Science Editors:

Feng Y. Modeling and regularization in tomographic reconstruction for Compton camera imaging : Modélisation et régularisation en reconstruction tomographique pour l'imagerie par caméra Compton. [Doctoral Dissertation]. Lyon; 2019. Available from: http://www.theses.fr/2019LYSEI084

28. Garti, Sara. Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR).

Degree: Docteur es, Mécanique des fluides Energétique, Procédés, 2020, Université Grenoble Alpes (ComUE)

URL: http://www.theses.fr/2020GREAI016

► Les réacteurs de quatrième génération sont développés dans le but de renouveler la filière énergétique du nucléaire avec des réacteurs plus sûrs, optimisant la consommation… (more)

▼ Les réacteurs de quatrième génération sont développés dans le but de renouveler la filière énergétique du nucléaire avec des réacteurs plus sûrs, optimisant la consommation du minerai uranium et produisant moins de déchets de vie longue. La France a investi dans le développement de la technologie des réacteurs à neutrons rapides refroidis au sodium. Par le passé, des prototypes ont été construits et exploités tels que RAPSODIE, PHENIX, SUPERPHENIX ; et depuis 2006, le CEA est en charge de la conception du futur prototype de cette filière : ASTRID. C’est dans ce cadre que les équipes du Commissariat à l’énergie atomique travaillent sur l’élaboration de moyens instrumentaux permettant de garantir l’intégrité absolue de la première barrière de confinement : la gaine des aiguilles combustibles. En effet, le niveau de sûreté à atteindre dans le programme génération 4 oblige l’exploitant à surveiller en continu la propreté du fluide caloporteur primaire. Pour assurer cette fonction de sûreté, différents systèmes sont implémentés tels que les systèmes de détection des neutrons différés (DND) et les systèmes de spectrométrie gamma. Ces systèmes sont en continuelle mutation depuis leurs premières exploitations par des programmes R&D assurant la prise en compte du retour d’exploitation de ces instruments et la remise à niveau en regard des avancées technologiques et des nouveaux moyens numériques de conception. L’instrumentation historique pour le suivi isotopique des gaz de fission par spectrométrie gamma est très bruitée et est compromise par la présence de lignes à retard d’environ 15 minutes nécessaires à la désactivation du 23Ne (T1/2 =38 s). De plus, l’autre source de bruit, i.e. l’41Ar, présentant une période de 110 minutes, n’a pas été filtrée par cette instrumentation. En effet, ce dernier ne perd que 7% de son activité dans ces lignes à retard.Au regard des exigences de sûreté fixées pour les RNR-Na, nous étudierons dans le cadre de cette thèse l’apport potentiel d’une instrumentation bas bruit au moyen d’un système à suppression Compton intégré au poste de mesure RNR-Na. L’enjeu majeur d’une telle instrumentation serait, d’une part, d’enrichir le diagnostic par la détection des produits de fission de courte période (~3 min), lesquels peuvent signer précocement une mise en contact entre le combustible et le caloporteur dangereuse pour la sûreté du réacteur, d’autre part, d’assurer une détection rapide par l’amélioration du temps de réponse de la mesure.Dans un premier temps, le terme source des produits de fission a été caractérisé par la mise en équation des différents phénomènes physiques régissant le comportement des gaz de fission dans un environnement de type RNR-Na faisant suite à une rupture de gaine. Des activités attendues des produits de fission sont ainsi estimées. Dans un second temps, nous avons procédé à l’étude numérique, au moyen de la méthode Monte Carlo, d’une instrumentation bas bruit, à sa validation expérimentale, puis à son optimisation. Enfin, nous avons implémenté la modélisation de la mesure… Advisors/Committee Members: Jammes, Christian (thesis director), Coulon, Romain (thesis director).

Subjects/Keywords: Spectrométrie gamma; Système à suppression Compton; Réacteurs à neutrons rapides; Instrumentation nucléaire; Méthodes Monte Carlo; Mesure bas bruit Compton; Gamma-Ray spectrometry; Compton suppressor system; Sodium fast reactors; Nuclear instrumentation; Monte-Carlo methods; Low background; 620

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Garti, S. (2020). Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR). (Doctoral Dissertation). Université Grenoble Alpes (ComUE). Retrieved from http://www.theses.fr/2020GREAI016

Chicago Manual of Style (16^th Edition):

Garti, Sara. “Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR).” 2020. Doctoral Dissertation, Université Grenoble Alpes (ComUE). Accessed January 15, 2021. http://www.theses.fr/2020GREAI016.

MLA Handbook (7^th Edition):

Garti, Sara. “Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR).” 2020. Web. 15 Jan 2021.

Vancouver:

Garti S. Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR). [Internet] [Doctoral dissertation]. Université Grenoble Alpes (ComUE); 2020. [cited 2021 Jan 15]. Available from: http://www.theses.fr/2020GREAI016.

Council of Science Editors:

Garti S. Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR). [Doctoral Dissertation]. Université Grenoble Alpes (ComUE); 2020. Available from: http://www.theses.fr/2020GREAI016

29. Garti, Sara. Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR).

Degree: Docteur es, Mécanique des fluides Energétique, Procédés, 2020, Université Grenoble Alpes

URL: http://www.theses.fr/2020GRALI016

► Les réacteurs de quatrième génération sont développés dans le but de renouveler la filière énergétique du nucléaire avec des réacteurs plus sûrs, optimisant la consommation… (more)

▼ Les réacteurs de quatrième génération sont développés dans le but de renouveler la filière énergétique du nucléaire avec des réacteurs plus sûrs, optimisant la consommation du minerai uranium et produisant moins de déchets de vie longue. La France a investi dans le développement de la technologie des réacteurs à neutrons rapides refroidis au sodium. Par le passé, des prototypes ont été construits et exploités tels que RAPSODIE, PHENIX, SUPERPHENIX ; et depuis 2006, le CEA est en charge de la conception du futur prototype de cette filière : ASTRID. C’est dans ce cadre que les équipes du Commissariat à l’énergie atomique travaillent sur l’élaboration de moyens instrumentaux permettant de garantir l’intégrité absolue de la première barrière de confinement : la gaine des aiguilles combustibles. En effet, le niveau de sûreté à atteindre dans le programme génération 4 oblige l’exploitant à surveiller en continu la propreté du fluide caloporteur primaire. Pour assurer cette fonction de sûreté, différents systèmes sont implémentés tels que les systèmes de détection des neutrons différés (DND) et les systèmes de spectrométrie gamma. Ces systèmes sont en continuelle mutation depuis leurs premières exploitations par des programmes R&D assurant la prise en compte du retour d’exploitation de ces instruments et la remise à niveau en regard des avancées technologiques et des nouveaux moyens numériques de conception. L’instrumentation historique pour le suivi isotopique des gaz de fission par spectrométrie gamma est très bruitée et est compromise par la présence de lignes à retard d’environ 15 minutes nécessaires à la désactivation du 23Ne (T1/2 =38 s). De plus, l’autre source de bruit, i.e. l’41Ar, présentant une période de 110 minutes, n’a pas été filtrée par cette instrumentation. En effet, ce dernier ne perd que 7% de son activité dans ces lignes à retard.Au regard des exigences de sûreté fixées pour les RNR-Na, nous étudierons dans le cadre de cette thèse l’apport potentiel d’une instrumentation bas bruit au moyen d’un système à suppression Compton intégré au poste de mesure RNR-Na. L’enjeu majeur d’une telle instrumentation serait, d’une part, d’enrichir le diagnostic par la détection des produits de fission de courte période (~3 min), lesquels peuvent signer précocement une mise en contact entre le combustible et le caloporteur dangereuse pour la sûreté du réacteur, d’autre part, d’assurer une détection rapide par l’amélioration du temps de réponse de la mesure.Dans un premier temps, le terme source des produits de fission a été caractérisé par la mise en équation des différents phénomènes physiques régissant le comportement des gaz de fission dans un environnement de type RNR-Na faisant suite à une rupture de gaine. Des activités attendues des produits de fission sont ainsi estimées. Dans un second temps, nous avons procédé à l’étude numérique, au moyen de la méthode Monte Carlo, d’une instrumentation bas bruit, à sa validation expérimentale, puis à son optimisation. Enfin, nous avons implémenté la modélisation de la mesure… Advisors/Committee Members: Jammes, Christian (thesis director), Coulon, Romain (thesis director).

Subjects/Keywords: Spectrométrie gamma; Système à suppression Compton; Réacteurs à neutrons rapides; Instrumentation nucléaire; Méthodes Monte Carlo; Mesure bas bruit Compton; Gamma-Ray spectrometry; Compton suppressor system; Sodium fast reactors; Nuclear instrumentation; Monte-Carlo methods; Low background; 620

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Garti, S. (2020). Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR). (Doctoral Dissertation). Université Grenoble Alpes. Retrieved from http://www.theses.fr/2020GRALI016

Chicago Manual of Style (16^th Edition):

Garti, Sara. “Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR).” 2020. Doctoral Dissertation, Université Grenoble Alpes. Accessed January 15, 2021. http://www.theses.fr/2020GRALI016.

MLA Handbook (7^th Edition):

Garti, Sara. “Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR).” 2020. Web. 15 Jan 2021.

Vancouver:

Garti S. Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR). [Internet] [Doctoral dissertation]. Université Grenoble Alpes; 2020. [cited 2021 Jan 15]. Available from: http://www.theses.fr/2020GRALI016.

Council of Science Editors:

Garti S. Spectrométrie gamma haute résolution et bas bruit Compton pour la détection des ruptures de gaine dans les réacteurs rapides refroidis au sodium : High resolution and low-background gamma spectrometry for clad failure detection in Sodium Fast Reactors (SFR). [Doctoral Dissertation]. Université Grenoble Alpes; 2020. Available from: http://www.theses.fr/2020GRALI016

30. Wahl, Christopher G. Imaging, Detection, and Identification Algorithms for Position-Sensitive Gamma-Ray Detectors.

Degree: PhD, Nuclear Engineering & Radiological Sciences, 2011, University of Michigan

URL: http://hdl.handle.net/2027.42/89797

► Three-dimensional-position-sensitive semiconductors record both the locations and energies of gamma-ray interactions with high resolution, enabling spectroscopy and imaging of gamma-ray-emitting materials. Imaging enables the detection… (more)

▼ Three-dimensional-position-sensitive semiconductors record both the locations and energies of gamma-ray interactions with high resolution, enabling spectroscopy and imaging of gamma-ray-emitting materials. Imaging enables the detection of point sources of gamma rays in an otherwise extended-source background, even when the background spectrum is unknown and may share the point source's spectrum. The generalized likelihood ratio test (GLRT) and source-intensity test (SIT) are applied to this situation to detect one-or-more unshielded point sources from a library of isotopes in a spectrally unknown or known background when the background intensity varies spatially by a factor of two or less. In addition to estimating the number of sources present, their activities, isotopes, and directions from the detector are estimated. Experimental and some simulated results are presented for a single detector and an 18-detector array of 2 cm by 2 cm by 1.5 cm CdZnTe crystals and compared with the performance of spectral-only detection when the background and source are assumed to be spectrally different. Furthermore, the expected detection performance of the 18-detector array system is investigated statistically using experimental data in the case where the background is distinct spectrally from the point source and the possible source location and isotopic identity are known. Including imaging gave at least 7% higher SNR compared to ignoring the image dimension. Also, imaging methods based on the maximum-likelihood expectation-maximization method are introduced to determine the spatial distribution of isotopes and to find the activity distributions within targets moving with known motion through a radioactive background. Software has also been developed to support the analysis of the data from 3D-position-sensitive spectroscopic systems, for a range of detector designs and applications. The software design and unique features that allow fast multidimensional data analysis are presented, along with parallel computing performance. Advisors/Committee Members: He, Zhong (committee member), Fessler, Jeffrey A. (committee member), Knoll, Glenn F. (committee member), Scott, Clayton D. (committee member).

Subjects/Keywords: Radiation Detection; Gamma-ray Imager; Nuclear Detection; CdZnTe; Imaging Software; Compton Imaging; Nuclear Engineering and Radiological Sciences; Engineering

…imaging of gamma-ray-emitting materials. Imaging enables the detection of point sources of… …locations and energies of gamma-ray interactions with high resolution, enabling spectroscopy and… …of a roadside portal monitor. The menagerie of gamma-ray detectors includes detectors that… …harvest either total count rates or, the best of them, muddy gamma-ray energy distributions. In… …map the gamma-ray energy distribution in all directions, and with a companion, they…

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Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wahl, C. G. (2011). Imaging, Detection, and Identification Algorithms for Position-Sensitive Gamma-Ray Detectors. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/89797

Chicago Manual of Style (16^th Edition):

Wahl, Christopher G. “Imaging, Detection, and Identification Algorithms for Position-Sensitive Gamma-Ray Detectors.” 2011. Doctoral Dissertation, University of Michigan. Accessed January 15, 2021. http://hdl.handle.net/2027.42/89797.

MLA Handbook (7^th Edition):

Wahl, Christopher G. “Imaging, Detection, and Identification Algorithms for Position-Sensitive Gamma-Ray Detectors.” 2011. Web. 15 Jan 2021.

Vancouver:

Wahl CG. Imaging, Detection, and Identification Algorithms for Position-Sensitive Gamma-Ray Detectors. [Internet] [Doctoral dissertation]. University of Michigan; 2011. [cited 2021 Jan 15]. Available from: http://hdl.handle.net/2027.42/89797.

Council of Science Editors:

Wahl CG. Imaging, Detection, and Identification Algorithms for Position-Sensitive Gamma-Ray Detectors. [Doctoral Dissertation]. University of Michigan; 2011. Available from: http://hdl.handle.net/2027.42/89797

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