subject:(MAGIC Gamma ray Active galactic nuclei Blazar Black hole)

1. 小谷, 一仁. MAGIC望遠鏡による未知赤方偏移HBL天体MAGIC J2001+439の観測と赤方偏移推定および多波長同時SEDの放射モデル解釈 : MAGIC ボウエンキョウニヨルミチセキホウヘンイ HBL テンタイ MAGIC J2001+439 ノカンソクトセキホウヘンイスイテイオヨビタハチョウドウジ SED ノホウシャモデルカイシャク.

Degree: 博士(理学), 2015, Tokai University Repository / 東海大学

URL: https://opac.time.u-tokai.ac.jp/webopac/TD00000131

Subjects/Keywords: MAGIC, ガンマ線, 活動銀河核, ブレーザー, ブラックホール; MAGIC, Gamma-ray, Active galactic nuclei, Blazar, Black hole

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APA (6^th Edition):

小谷, �. (2015). MAGIC望遠鏡による未知赤方偏移HBL天体MAGIC J2001+439の観測と赤方偏移推定および多波長同時SEDの放射モデル解釈 : MAGIC ボウエンキョウニヨルミチセキホウヘンイ HBL テンタイ MAGIC J2001+439 ノカンソクトセキホウヘンイスイテイオヨビタハチョウドウジ SED ノホウシャモデルカイシャク. (Thesis). Tokai University Repository / 東海大学. Retrieved from https://opac.time.u-tokai.ac.jp/webopac/TD00000131

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):

小谷, 一仁. “MAGIC望遠鏡による未知赤方偏移HBL天体MAGIC J2001+439の観測と赤方偏移推定および多波長同時SEDの放射モデル解釈 : MAGIC ボウエンキョウニヨルミチセキホウヘンイ HBL テンタイ MAGIC J2001+439 ノカンソクトセキホウヘンイスイテイオヨビタハチョウドウジ SED ノホウシャモデルカイシャク.” 2015. Thesis, Tokai University Repository / 東海大学. Accessed January 19, 2021. https://opac.time.u-tokai.ac.jp/webopac/TD00000131.

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

MLA Handbook (7^th Edition):

小谷, 一仁. “MAGIC望遠鏡による未知赤方偏移HBL天体MAGIC J2001+439の観測と赤方偏移推定および多波長同時SEDの放射モデル解釈 : MAGIC ボウエンキョウニヨルミチセキホウヘンイ HBL テンタイ MAGIC J2001+439 ノカンソクトセキホウヘンイスイテイオヨビタハチョウドウジ SED ノホウシャモデルカイシャク.” 2015. Web. 19 Jan 2021.

Vancouver:

小谷 �. MAGIC望遠鏡による未知赤方偏移HBL天体MAGIC J2001+439の観測と赤方偏移推定および多波長同時SEDの放射モデル解釈 : MAGIC ボウエンキョウニヨルミチセキホウヘンイ HBL テンタイ MAGIC J2001+439 ノカンソクトセキホウヘンイスイテイオヨビタハチョウドウジ SED ノホウシャモデルカイシャク. [Internet] [Thesis]. Tokai University Repository / 東海大学; 2015. [cited 2021 Jan 19]. Available from: https://opac.time.u-tokai.ac.jp/webopac/TD00000131.

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

Council of Science Editors:

小谷 �. MAGIC望遠鏡による未知赤方偏移HBL天体MAGIC J2001+439の観測と赤方偏移推定および多波長同時SEDの放射モデル解釈 : MAGIC ボウエンキョウニヨルミチセキホウヘンイ HBL テンタイ MAGIC J2001+439 ノカンソクトセキホウヘンイスイテイオヨビタハチョウドウジ SED ノホウシャモデルカイシャク. [Thesis]. Tokai University Repository / 東海大学; 2015. Available from: https://opac.time.u-tokai.ac.jp/webopac/TD00000131

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

2. Backes, Michael. Long-term observations of the TeV blazar 1ES1959+650.

Degree: 2012, Technische Universität Dortmund

URL: http://hdl.handle.net/2003/29464

► Throughout this thesis, the spectral and temporal long-term behavior of the Active Galactic Nucleus (AGN) 1ES1959+650 is studied. Being a blazar, i.e. an AGN with… (more)

▼ Throughout this thesis, the spectral and temporal long-term behavior of the Active Galactic Nucleus (AGN) 1ES1959+650 is studied. Being a blazar, i.e. an AGN with a highly relativistic plasma outflow pointing towards the Earth, and having shown strong hints of hadronic emission processes in the past, 1ES1959+650 is a primary candidate for a source of cosmic rays. The origin of these ultra high energetic charged particles is the central question of astroparticle physics. Therefore, 1ES1959+650 has been monitored with the MAGIC telescope since 2004, measuring very high energy (VHE) gamma-rays. The resulting time-integrated energy spectrum reported here is by far the most exact one determined for this source up to now. Also the temporal variability for different wavelength bands, which should be connected in the case of most non-hadronic emission processes, is examined in this thesis. While strong variations occur in the optical and X-rays, the VHE gamma-ray emission is compatible with a constant flux. Furthermore, the time-integrated spectral energy distribution is compiled from radio to VHE gamma-rays and modeled for hadronic and leptonic emission scenarios to unveil the character of the emitting particles. Unexpected results are obtained on the spectral shape of the observed blazar, especially in high energy gamma-rays. By this, 1ES1959+650 is one of the very first high frequency peaked blazars whose non-thermal emission cannot be explained with a single-zone SSC model. Additionally, in this thesis the idea of long-term monitoring of blazars at VHE gamma-rays is pursued further. The FACT telescope, the first application of G-APDs as photosensors in an imaging atmospheric Cherenkov telescope, has recently been constructed and already during its commissioning phase reported on very promising first results. After the commissioning, it will be devoted to monitoring observations of bright blazars. For the construction of this telescope, the completely reworked aluminum mirrors have been characterized, including measurements of the focal lengths and the spot sizes of a reflected point-like light source. Finally, it is presented that DWARF, a global network of a small number of Cherenkov telescopes dedicated to monitoring observations of TeV-bright blazars, will be well suited to obtain comprehensive, well sampled lightcurves which are needed to study possible temporal correlations between VHE gamma-rays and other wavelengths. Advisors/Committee Members: Rhode, Wolfgang.

Subjects/Keywords: active galactic nuclei (AGN); blazar; FACT; gamma-ray astronomy; lightcurves; MAGIC; spectral energy distribution (SED); 530; Aktiver galaktischer Kern; Blazar; Gammaastronomie; Lichtkurve; Radioteleskop

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

APA (6^th Edition):

Backes, M. (2012). Long-term observations of the TeV blazar 1ES1959+650. (Thesis). Technische Universität Dortmund. Retrieved from http://hdl.handle.net/2003/29464

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):

Backes, Michael. “Long-term observations of the TeV blazar 1ES1959+650.” 2012. Thesis, Technische Universität Dortmund. Accessed January 19, 2021. http://hdl.handle.net/2003/29464.

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

MLA Handbook (7^th Edition):

Backes, Michael. “Long-term observations of the TeV blazar 1ES1959+650.” 2012. Web. 19 Jan 2021.

Vancouver:

Backes M. Long-term observations of the TeV blazar 1ES1959+650. [Internet] [Thesis]. Technische Universität Dortmund; 2012. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2003/29464.

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

Council of Science Editors:

Backes M. Long-term observations of the TeV blazar 1ES1959+650. [Thesis]. Technische Universität Dortmund; 2012. Available from: http://hdl.handle.net/2003/29464

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

3. Backes, Michael. Long-term observations of the TeV blazar 1ES1959+650: Temporal and spectral behavior in the multi-wavelength context.

Degree: 2012, Technische Universität Dortmund

URL: http://dx.doi.org/10.17877/DE290R-4809

► Throughout this thesis, the spectral and temporal long-term behavior of the Active Galactic Nucleus (AGN) 1ES1959+650 is studied. Being a blazar, i.e. an AGN with… (more)

▼ Throughout this thesis, the spectral and temporal long-term behavior of the Active Galactic Nucleus (AGN) 1ES1959+650 is studied. Being a blazar, i.e. an AGN with a highly relativistic plasma outflow pointing towards the Earth, and having shown strong hints of hadronic emission processes in the past, 1ES1959+650 is a primary candidate for a source of cosmic rays. The origin of these ultra high energetic charged particles is the central question of astroparticle physics. Therefore, 1ES1959+650 has been monitored with the MAGIC telescope since 2004, measuring very high energy (VHE) gamma-rays. The resulting time-integrated energy spectrum reported here is by far the most exact one determined for this source up to now. Also the temporal variability for different wavelength bands, which should be connected in the case of most non-hadronic emission processes, is examined in this thesis. While strong variations occur in the optical and X-rays, the VHE gamma-ray emission is compatible with a constant flux. Furthermore, the time-integrated spectral energy distribution is compiled from radio to VHE gamma-rays and modeled for hadronic and leptonic emission scenarios to unveil the character of the emitting particles. Unexpected results are obtained on the spectral shape of the observed blazar, especially in high energy gamma-rays. By this, 1ES1959+650 is one of the very first high frequency peaked blazars whose non-thermal emission cannot be explained with a single-zone SSC model. Additionally, in this thesis the idea of long-term monitoring of blazars at VHE gamma-rays is pursued further. The FACT telescope, the first application of G-APDs as photosensors in an imaging atmospheric Cherenkov telescope, has recently been constructed and already during its commissioning phase reported on very promising first results. After the commissioning, it will be devoted to monitoring observations of bright blazars. For the construction of this telescope, the completely reworked aluminum mirrors have been characterized, including measurements of the focal lengths and the spot sizes of a reflected point-like light source. Finally, it is presented that DWARF, a global network of a small number of Cherenkov telescopes dedicated to monitoring observations of TeV-bright blazars, will be well suited to obtain comprehensive, well sampled lightcurves which are needed to study possible temporal correlations between VHE gamma-rays and other wavelengths. Advisors/Committee Members: Rhode, Wolfgang (advisor), Becker, Julia K. (referee).

Subjects/Keywords: active galactic nuclei (AGN); blazar; FACT; gamma-ray astronomy; lightcurves; MAGIC; spectral energy distribution (SED); 530; Aktiver galaktischer Kern; Blazar; Gammaastronomie; Lichtkurve; Radioteleskop

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):

Backes, M. (2012). Long-term observations of the TeV blazar 1ES1959+650: Temporal and spectral behavior in the multi-wavelength context. (Doctoral Dissertation). Technische Universität Dortmund. Retrieved from http://dx.doi.org/10.17877/DE290R-4809

Chicago Manual of Style (16^th Edition):

Backes, Michael. “Long-term observations of the TeV blazar 1ES1959+650: Temporal and spectral behavior in the multi-wavelength context.” 2012. Doctoral Dissertation, Technische Universität Dortmund. Accessed January 19, 2021. http://dx.doi.org/10.17877/DE290R-4809.

MLA Handbook (7^th Edition):

Backes, Michael. “Long-term observations of the TeV blazar 1ES1959+650: Temporal and spectral behavior in the multi-wavelength context.” 2012. Web. 19 Jan 2021.

Vancouver:

Backes M. Long-term observations of the TeV blazar 1ES1959+650: Temporal and spectral behavior in the multi-wavelength context. [Internet] [Doctoral dissertation]. Technische Universität Dortmund; 2012. [cited 2021 Jan 19]. Available from: http://dx.doi.org/10.17877/DE290R-4809.

Council of Science Editors:

Backes M. Long-term observations of the TeV blazar 1ES1959+650: Temporal and spectral behavior in the multi-wavelength context. [Doctoral Dissertation]. Technische Universität Dortmund; 2012. Available from: http://dx.doi.org/10.17877/DE290R-4809

Louisiana State University

4. Rodi, James Craig. Earth occultation imaging of the low energy gamma-ray sky with the Fermi/Gamma-ray Burst Monitor.

Degree: PhD, Physical Sciences and Mathematics, 2013, Louisiana State University

URL: etd-04042013-150012 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1672

► The hard X-ray/soft gamma-ray sky is highly variable as source intensities can vary on timescales from fractions of a second to years. The type of… (more)

▼ The hard X-ray/soft gamma-ray sky is highly variable as source intensities can vary on timescales from fractions of a second to years. The type of sources emitting at these energies often include compact objects such as white dwarfs, neutron stars, and black holes interacting with the surrounding environment, which enables the study of the properties and characteristics of these exotic objects. Because the interactions with the environment is often through accretion, most of the emission is in X-rays and gamma-rays Frank et al. 1992 making this energy range critical to understanding the relevant physical processes and mechanisms. Hard X-ray/soft gamma-ray (10 keV - 1 MeV) photons are difficult to focus requiring alternative observing techniques to monitor sources in this energy range. One method is the Earth Occultation Technique (EOT) that uses the rapid change in count rate (~sim 10 sec) due to a source passing behind (or out from behind) the Earth to measure source intensity. The EOT has been applied to the Gamma-ray Burst Monitor (GBM) on board the NASA Fermi satellite since its launch in 2008 and has been performing all-sky monitoring of a predetermined catalog of ~200 hard X-ray/soft gamma-ray sources. Because the EOT requires prior knowledge of a source's position for monitoring, I have developed a tomographic imaging method Imaging with a Differential filter using the Earth Occultation Method (IDEOM) to generate all-sky images in search of sources absent from the input catalog to construct a catalog as complete as possible. A complete catalog is important for reducing a source of systematic error as the flux from an unaccounted-for source can be attributed to a known source thus biasing its flux measurement. Approximately 4 years of GBM data have been analyzed to produce all-sky images covering the 12-50 keV, 50-100 keV, and 100-300 keV energy bands with 16 sources being added to the GBM catalog. All-sky images are shown for each energy range along with a table listing the sources detected by IDEOM. Also, the list of sources detected by IDEOM has been compared to those detected by EOT in each energy band. In addition, spectral analysis was performed in the four persistent sources detected by GBM and the Fermi/Large Area Telescope (LAT) (NGC 1275, 3C 273, Cen A, and the Crab) thus providing energy coverage from ~10 keV to ~100 GeV to study the high energy emission processes of these sources. Spectral results from GBM and LAT are presented and shown to be in agreement with previously proposed models in the literature. Finally, I have also developed a transient search algorithm to search for flares and outbursts in the light curves of GBM sources. This algorithm was applied to the ~200 sources in the GBM catalog to search for transient events during the first four years of the mission in four energy bands covering 12-500 keV. The search resulted in 168 transient events found from 65 sources with 7 events detected above 50 keV and 1 event detected above 100 keV (XTE J1752-223). A table of start and stop times are…

Subjects/Keywords: tomographic imaging; hard X-ray; Active Galactic Nuclei; Black Hole Binaries

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

APA (6^th Edition):

Rodi, J. C. (2013). Earth occultation imaging of the low energy gamma-ray sky with the Fermi/Gamma-ray Burst Monitor. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-04042013-150012 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1672

Chicago Manual of Style (16^th Edition):

Rodi, James Craig. “Earth occultation imaging of the low energy gamma-ray sky with the Fermi/Gamma-ray Burst Monitor.” 2013. Doctoral Dissertation, Louisiana State University. Accessed January 19, 2021. etd-04042013-150012 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1672.

MLA Handbook (7^th Edition):

Rodi, James Craig. “Earth occultation imaging of the low energy gamma-ray sky with the Fermi/Gamma-ray Burst Monitor.” 2013. Web. 19 Jan 2021.

Vancouver:

Rodi JC. Earth occultation imaging of the low energy gamma-ray sky with the Fermi/Gamma-ray Burst Monitor. [Internet] [Doctoral dissertation]. Louisiana State University; 2013. [cited 2021 Jan 19]. Available from: etd-04042013-150012 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1672.

Council of Science Editors:

Rodi JC. Earth occultation imaging of the low energy gamma-ray sky with the Fermi/Gamma-ray Burst Monitor. [Doctoral Dissertation]. Louisiana State University; 2013. Available from: etd-04042013-150012 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1672

Indian Institute of Science

5. Bhattacharya, Debbijoy. Origin Of The Extragalactic Gamma-Ray Background.

Degree: PhD, Faculty of Science, 2013, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/2252

► It is evident that the origin of EGRB is not well established. In this thesis I examine the unresolved discrete origin of EGRB. The contribution… (more)

▼ It is evident that the origin of EGRB is not well established. In this thesis I examine the unresolved discrete origin of EGRB. The contribution from normal galaxies, starburst galaxies and AGNs to the EGRB is examined. The second chapter includes the methodology used to find the contributions from different source classes. In the third chapter the contribution from normal and starburst galaxies is discussed. A methodology is developed to derive the contribution from normal and starburst galaxies to the EGRB considering all the major γ-ray production processes in these galaxies. The calculations in this thesis consider the detailed γ-ray measurements of our galaxy(Hunter etal.1997) to derive suitable scaling relations to extend the analysis beyond the Milky Way. It is assumed that all normal and starburst galaxies also have similar γ-ray spectra. A relationship is derived between the γ-ray luminosity and SFR of a normal galaxy. Infrared luminosity of a normal galaxy is used as a tracer of SFR of that galaxy (Kewley et al.2002). For starburst galaxies, the contribution depends on the relative ratio(β)of cosmic-ray enhancement per SFR w.r.t the Milky Way. To find the proportionality constants between cosmic-ray production rate and SFR of starburst galaxies, M82 has been taken as a standard. Contribution from FSRQs and BL Lacs to the EGRB is discussed in the fourth chapter. FSRQs and BL Lacs are considered as separate source classes, and their luminosity functions are constructed separately from the recent identifications of EGRET sources(Sowards-Emmerd,Romani&Michelson2003 and Sowards-Emmerd et al.2004) which almost doubled the blazers count than that used by Chiang & Mukher-jee(1998). Radio-loud AGNs with all possible jet to line-of-sight angle (SSRQs, FR IIs, FR Is) are termed here off-axis AGNs. It is considered that SSRQs and FSRQs and FR IIs are from one parent population, BL Lacs and FR Is are from another parent population. The scenario considered includes an AGN jet which slows down as it moves away from the central source. The contributions from these AGNs (relative to the FSRQs and BL Lacs contribution) are discussed in chapter five. Chapter six briefly summarised the findings from the thesis. Advisors/Committee Members: Choudhuri, Arnab Rai (advisor).

Subjects/Keywords: Gamma-Ray Astronomy; Blazars; Extragalatic Gamma-Ray Background (EGRB); Starburst Galaxies; Galaxies; Active Galactic Nuclei; Active Galaxies; Galactic Nuclei; ASTROSAT; Astronomy

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

APA (6^th Edition):

Bhattacharya, D. (2013). Origin Of The Extragalactic Gamma-Ray Background. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2252

Chicago Manual of Style (16^th Edition):

Bhattacharya, Debbijoy. “Origin Of The Extragalactic Gamma-Ray Background.” 2013. Doctoral Dissertation, Indian Institute of Science. Accessed January 19, 2021. http://etd.iisc.ac.in/handle/2005/2252.

MLA Handbook (7^th Edition):

Bhattacharya, Debbijoy. “Origin Of The Extragalactic Gamma-Ray Background.” 2013. Web. 19 Jan 2021.

Vancouver:

Bhattacharya D. Origin Of The Extragalactic Gamma-Ray Background. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2013. [cited 2021 Jan 19]. Available from: http://etd.iisc.ac.in/handle/2005/2252.

Council of Science Editors:

Bhattacharya D. Origin Of The Extragalactic Gamma-Ray Background. [Doctoral Dissertation]. Indian Institute of Science; 2013. Available from: http://etd.iisc.ac.in/handle/2005/2252

University of Michigan

6. Foord, Adi. Discovering the Missing Population of AGN Pairs with Chandra.

Degree: PhD, Astronomy and Astrophysics, 2020, University of Michigan

URL: http://hdl.handle.net/2027.42/163194

► Although the first supermassive black hole (SMBH) was observed over 100 years ago, the details regarding how they form, evolve, and impact their surroundings remain… (more)

▼ Although the first supermassive black hole (SMBH) was observed over 100 years ago, the details regarding how they form, evolve, and impact their surroundings remain active topics of research. In fact, only over the past 5 years has the existence of black holes been confirmed via the advent of detectors such as the Advanced Laser Interferometer Gravitational Wave Observatory (LIGO) and the Event Horizon Telescope (EHT). From an observational perspective, although all massive galaxies are thought to harbor nuclear SMBHs, the observability is dependent on the accretion activity. The activity of accreting SMBHs, or Active Galactic Nuclei (AGN), is expected to evolve with time and is likely a function of the ability to efficiently channel gas inflow to the galactic center. Many black hole feeding mechanisms exist, such as gravitational instabilities in galaxies that are barred or nucleated, gas dynamic processes involving multiple black holes, and major galaxy interactions. To further complicate the matter, it is possible that more than one mechanism plays a role at any given time. However, analyzing which SMBHs are active, and why, is vital to understanding various feedback processes and how the growth of a SMBH and its host galaxy are tied. In this dissertation, I present various analyses that are all focused on studying the activity of SMBHs in various environments. Specifically, I have studied a population of AGN in nucleated galaxies to analyze how nuclear star clusters affect SMBH activity (Chapter 2), and a binary AGN candidate (two SMBHs that are gravitationally bound; Chapter 3) that did not appear to be undergoing any major merger. However, the majority of my dissertation focuses on detecting and analyzing AGN pairs, (``dual AGN", if the SMBHs are not yet gravitationally bound). Despite the importance of dual AGN to wide-ranging astrophysical fields such as galaxy formation and gravitational waves, the rate of dual AGN has yet to be accurately measured. Yet, the rate of dual AGN can inform us of the role galaxy mergers play in triggering AGN, timescales for post-merger SMBHs to sink to the center of the potential well, as well as merger-related feedback physics. Dual AGN that are widely separated relative to the instrument PSF and have near unity flux ratios are easy to identify, however dual AGN with small separations and/or flux ratios can only be distinguished from a single AGN with advanced statistical analysis. As a result, very few dual AGN have been confirmed. Thus, I've developed a tool called BAYMAX (Bayesian Analysis of Multiple AGN in X-rays), that quantitatively evaluates whether a given source in a Chandra observation is composed of a single or multiple point sources, using a Bayesian framework. With BAYMAX, I am methodically expanding the known population of multiple AGN systems (Chapters 5 and 6), while learning more about their preferential environments via multi-wavelength (Optical, IR, and X-ray) analyses. Advisors/Committee Members: Gultekin, Kayhan (committee member), McKay, Timothy A (committee member), Comerford, Julia M (committee member), Gallo, Elena (committee member), Hodges-Kluck, Edmund (committee member), Miller, Jon Matthew (committee member).

Subjects/Keywords: X-ray Astronomy; Supermassive Black Hole; Galaxy Mergers; Active Galactic Nuclei; Astronomy; Physics; Statistics and Numeric Data; Science

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

APA (6^th Edition):

Foord, A. (2020). Discovering the Missing Population of AGN Pairs with Chandra. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/163194

Chicago Manual of Style (16^th Edition):

Foord, Adi. “Discovering the Missing Population of AGN Pairs with Chandra.” 2020. Doctoral Dissertation, University of Michigan. Accessed January 19, 2021. http://hdl.handle.net/2027.42/163194.

MLA Handbook (7^th Edition):

Foord, Adi. “Discovering the Missing Population of AGN Pairs with Chandra.” 2020. Web. 19 Jan 2021.

Vancouver:

Foord A. Discovering the Missing Population of AGN Pairs with Chandra. [Internet] [Doctoral dissertation]. University of Michigan; 2020. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2027.42/163194.

Council of Science Editors:

Foord A. Discovering the Missing Population of AGN Pairs with Chandra. [Doctoral Dissertation]. University of Michigan; 2020. Available from: http://hdl.handle.net/2027.42/163194

7. Eichmann, Björn. Leptonic and hadronic radiation production in flaring blazars.

Degree: 2012, Technische Universität Dortmund

URL: http://hdl.handle.net/2003/29564

Subjects/Keywords: Active galactic nuclei (AGN); Blazar; Gamma ray astronomy; Neutrinos; Non-thermal radiation; 530; Aktiver galaktischer Kern; Blazar; Gamma-Burst; Neutrino

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

APA (6^th Edition):

Eichmann, B. (2012). Leptonic and hadronic radiation production in flaring blazars. (Thesis). Technische Universität Dortmund. Retrieved from http://hdl.handle.net/2003/29564

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):

Eichmann, Björn. “Leptonic and hadronic radiation production in flaring blazars.” 2012. Thesis, Technische Universität Dortmund. Accessed January 19, 2021. http://hdl.handle.net/2003/29564.

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

MLA Handbook (7^th Edition):

Eichmann, Björn. “Leptonic and hadronic radiation production in flaring blazars.” 2012. Web. 19 Jan 2021.

Vancouver:

Eichmann B. Leptonic and hadronic radiation production in flaring blazars. [Internet] [Thesis]. Technische Universität Dortmund; 2012. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2003/29564.

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

Council of Science Editors:

Eichmann B. Leptonic and hadronic radiation production in flaring blazars. [Thesis]. Technische Universität Dortmund; 2012. Available from: http://hdl.handle.net/2003/29564

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

8. Eichmann, Björn. Leptonic and hadronic radiation production in flaring blazars: A theoretical analysis of the temporal development of the emergent synchrotron, gamma ray and neutrino intensity.

Degree: 2012, Technische Universität Dortmund

URL: http://dx.doi.org/10.17877/DE290R-4822

Subjects/Keywords: Active galactic nuclei (AGN); Blazar; Gamma ray astronomy; Neutrinos; Non-thermal radiation; 530; Aktiver galaktischer Kern; Blazar; Gamma-Burst; Neutrino

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):

Eichmann, B. (2012). Leptonic and hadronic radiation production in flaring blazars: A theoretical analysis of the temporal development of the emergent synchrotron, gamma ray and neutrino intensity. (Doctoral Dissertation). Technische Universität Dortmund. Retrieved from http://dx.doi.org/10.17877/DE290R-4822

Chicago Manual of Style (16^th Edition):

Eichmann, Björn. “Leptonic and hadronic radiation production in flaring blazars: A theoretical analysis of the temporal development of the emergent synchrotron, gamma ray and neutrino intensity.” 2012. Doctoral Dissertation, Technische Universität Dortmund. Accessed January 19, 2021. http://dx.doi.org/10.17877/DE290R-4822.

MLA Handbook (7^th Edition):

Eichmann, Björn. “Leptonic and hadronic radiation production in flaring blazars: A theoretical analysis of the temporal development of the emergent synchrotron, gamma ray and neutrino intensity.” 2012. Web. 19 Jan 2021.

Vancouver:

Eichmann B. Leptonic and hadronic radiation production in flaring blazars: A theoretical analysis of the temporal development of the emergent synchrotron, gamma ray and neutrino intensity. [Internet] [Doctoral dissertation]. Technische Universität Dortmund; 2012. [cited 2021 Jan 19]. Available from: http://dx.doi.org/10.17877/DE290R-4822.

Council of Science Editors:

Eichmann B. Leptonic and hadronic radiation production in flaring blazars: A theoretical analysis of the temporal development of the emergent synchrotron, gamma ray and neutrino intensity. [Doctoral Dissertation]. Technische Universität Dortmund; 2012. Available from: http://dx.doi.org/10.17877/DE290R-4822

Rochester Institute of Technology

9. Lake, Brian Christopher. Polarization Properties of Broad Lines in Active Galactic Nuclei.

Degree: MS, School of Physics and Astronomy (COS), 2020, Rochester Institute of Technology

URL: https://scholarworks.rit.edu/theses/10444

► The center of every large galaxy is believed to host a supermassive black hole (SMBH). In some of these galaxies, the nuclear region is… (more)

Subjects/Keywords: Active galactic nuclei; AGN; SMBH; Spectropolarimetry; Supermassive black hole

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

APA (6^th Edition):

Lake, B. C. (2020). Polarization Properties of Broad Lines in Active Galactic Nuclei. (Masters Thesis). Rochester Institute of Technology. Retrieved from https://scholarworks.rit.edu/theses/10444

Chicago Manual of Style (16^th Edition):

Lake, Brian Christopher. “Polarization Properties of Broad Lines in Active Galactic Nuclei.” 2020. Masters Thesis, Rochester Institute of Technology. Accessed January 19, 2021. https://scholarworks.rit.edu/theses/10444.

MLA Handbook (7^th Edition):

Lake, Brian Christopher. “Polarization Properties of Broad Lines in Active Galactic Nuclei.” 2020. Web. 19 Jan 2021.

Vancouver:

Lake BC. Polarization Properties of Broad Lines in Active Galactic Nuclei. [Internet] [Masters thesis]. Rochester Institute of Technology; 2020. [cited 2021 Jan 19]. Available from: https://scholarworks.rit.edu/theses/10444.

Council of Science Editors:

Lake BC. Polarization Properties of Broad Lines in Active Galactic Nuclei. [Masters Thesis]. Rochester Institute of Technology; 2020. Available from: https://scholarworks.rit.edu/theses/10444

Université Paris-Sud – Paris XI

10. Wouters, Denis. Recherche de nouveaux bosons légers en astronomie de haute énergie : Search for new light bosons in high energy astronomy.

Degree: Docteur es, Physique, 2014, Université Paris-Sud – Paris XI

URL: http://www.theses.fr/2014PA112141

►

L'astronomie de haute énergie se concentre sur l'étude des phénomènes les plus violents de l'univers à partir d'observations dans une gamme d'énergie allant des rayons… (more)

▼

L'astronomie de haute énergie se concentre sur l'étude des phénomènes les plus violents de l'univers à partir d'observations dans une gamme d'énergie allant des rayons X aux rayons gammas de très hautes énergies (1 keV - 100 TeV). Ces phénomènes incluent par exemple les explosions de supernovae et leurs vestiges, les pulsars et les nébuleuses de vent de pulsar ou encore la formation de jets ultrarelativistes au niveau des noyaux actifs de galaxie. Leur compréhension fait appel à des processus de physique des particules bien connus qui seront décrits dans cette thèse. Par l'intermédiaire de photons de haute énergie, l'étude de ces phénomènes de haute énergie ouvre donc une fenêtre originale pour la recherche de physique au delà du modèle standard. Les concepts relatifs à l'émission et la propagation de photons de haute énergie sont introduits dans cette thèse et appliqués à l'étude de l'émission de sources extragalactiques ainsi que du fond de lumière extragalactique, affectant la propagation des photons de haute énergie dans l'univers. Dans le cadre de cette thèse, ces sources extragalactiques de photons de haute énergie sont observées afin de rechercher de nouveaux bosons légers, tels que ceux appartenant à la famille des particules de type axion (PTA). Les bases théoriques décrivant cette famille de particules sont présentées, ainsi que la phénoménologie associée. Notamment, en raison de leur couplage à deux photons, ces particules ont la propriété d'osciller avec des photons en présence de champ magnétique externe. Une nouvelle signature de la présence de telles oscillations dans des champs magnétiques turbulents, sous la forme d'irrégularités stochastiques dans le spectre en énergie, est étudiée et discutée. Cette signature est appliquée à la recherche de PTA avec le réseau de télescopes HESS, permettant d'obtenir pour la première fois des contraintes sur ces modèles à partir d'observations en astronomie gamma. La recherche de la même signature dans des observations en rayons X permet d'améliorer les contraintes actuelles pour les PTA de très basse masse et l'extension de ces contraintes à des modèles de modification de la gravité comme explication de la nature de l'énergie noire est également évoquée. Enfin, la recherche de PTA avec l'instrument d'astronomie gamma du futur, CTA, est discutée; en particulier, une nouvelle observable est proposée qui tire partie du grand nombre de sources attendu avec cet instrument.

High-Energy astronomy studies the most violent phenomena in the universe with observations in a large spectrum of energies ranging from X rays to very high energy gamma rays (1 keV - 100 TeV). Such phenomena could be for instance supernovae explosions and their remnants, pulsars and pulsar wind nebulae or ultra relativistic jets formation by active galactic nuclei. Understanding these phenomena requires to use well-known particle physics processes. By means of high energy photons, studying such phenomena enables one to search for physics beyond the standard model. Concepts regarding the emission…

Advisors/Committee Members: Brun, Pierre (thesis director).

Subjects/Keywords: Axions; Astronomie gamma; Noyaux actifs de galaxies; Axions; Gamma-ray astronomy; Active galactic nuclei

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

APA (6^th Edition):

Wouters, D. (2014). Recherche de nouveaux bosons légers en astronomie de haute énergie : Search for new light bosons in high energy astronomy. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2014PA112141

Chicago Manual of Style (16^th Edition):

Wouters, Denis. “Recherche de nouveaux bosons légers en astronomie de haute énergie : Search for new light bosons in high energy astronomy.” 2014. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed January 19, 2021. http://www.theses.fr/2014PA112141.

MLA Handbook (7^th Edition):

Wouters, Denis. “Recherche de nouveaux bosons légers en astronomie de haute énergie : Search for new light bosons in high energy astronomy.” 2014. Web. 19 Jan 2021.

Vancouver:

Wouters D. Recherche de nouveaux bosons légers en astronomie de haute énergie : Search for new light bosons in high energy astronomy. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2014. [cited 2021 Jan 19]. Available from: http://www.theses.fr/2014PA112141.

Council of Science Editors:

Wouters D. Recherche de nouveaux bosons légers en astronomie de haute énergie : Search for new light bosons in high energy astronomy. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2014. Available from: http://www.theses.fr/2014PA112141

Princeton University

11. Sironi, Lorenzo. Particle Acceleration and Nonthermal Emission in Relativistic Astrophysical Shocks .

Degree: PhD, 2011, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp01b2773v701

► The common observational feature of Pulsar Wind Nebulae (PWNe), gamma-ray bursts (GRBs), and AGN jets is a broad nonthermal spectrum of synchrotron and inverse Compton… (more)

▼ The common observational feature of Pulsar Wind Nebulae (PWNe), gamma-ray bursts (GRBs), and AGN jets is a broad nonthermal spectrum of synchrotron and inverse Compton radiation. It is usually assumed that the emitting electrons are accelerated to a power-law distribution at relativistic shocks, via the so-called Fermi mechanism. Despite decades of research, the Fermi acceleration process is still not understood from first principles. An assessment of the micro-physics of particle acceleration in relativistic shocks is of paramount importance to unveil the properties of astrophysical nonthermal sources, and it is the subject of this dissertation. In the first part of this thesis, I explore by means of fully-kinetic first-principle particle-in-cell (PIC) simulations the properties of relativistic shocks that propagate in electron-positron and electron-proton plasmas carrying uniform magnetic fields. I find that nonthermal particle acceleration only occurs if the upstream magnetization is weak (sigma<0.001), or if the pre-shock field is nearly aligned with the shock direction of propagation (quasi-parallel shocks). Relativistic shocks in PWNe, GRBs and AGN jets are usually thought to be appreciably magnetized (sigma>0.01) and quasi-perpendicular, yet they need to be efficient particle accelerators, in order to explain the prominent nonthermal signatures of these sources. Motivated by this discrepancy, I then relax the assumption of uniform pre-shock fields, and investigate the acceleration efficiency of perpendicular shocks that propagate in high-sigma flows with alternating magnetic fields. This is the geometry expected at the termination shock of pulsar winds, but it could also be relevant for Poynting-dominated jets in GRBs and AGNs. I show by means of PIC simulations that compression of the flow at the shock will force annihilation of nearby field lines, a process known as shock-driven reconnection. Magnetic reconnection can efficiently transfer the energy of alternating fields to the particles, generating flat power-law tails containing most of the particles. Finally, I directly relate the results of my PIC simulations to observations of nonthermal sources, by presenting a numerical technique that I have developed in order to extract ab initio photon spectra from PIC simulations of shocks. With this technique, I have modeled the emission from GRB jets, ruling out a class of models that relied on the so-called jitter radiation. This reinforces the idea that a detailed understanding of the micro-physics of particle acceleration in relativistic shocks is required in order to correctly interpret the emission signatures of astrophysical nonthermal sources. Advisors/Committee Members: Spitkovsky, Anatoly (advisor).

Subjects/Keywords: acceleration of particles; active galactic nuclei jets; gamma-ray bursts; nonthermal radiation; pulsars; shock waves

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

APA (6^th Edition):

Sironi, L. (2011). Particle Acceleration and Nonthermal Emission in Relativistic Astrophysical Shocks . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01b2773v701

Chicago Manual of Style (16^th Edition):

Sironi, Lorenzo. “Particle Acceleration and Nonthermal Emission in Relativistic Astrophysical Shocks .” 2011. Doctoral Dissertation, Princeton University. Accessed January 19, 2021. http://arks.princeton.edu/ark:/88435/dsp01b2773v701.

MLA Handbook (7^th Edition):

Sironi, Lorenzo. “Particle Acceleration and Nonthermal Emission in Relativistic Astrophysical Shocks .” 2011. Web. 19 Jan 2021.

Vancouver:

Sironi L. Particle Acceleration and Nonthermal Emission in Relativistic Astrophysical Shocks . [Internet] [Doctoral dissertation]. Princeton University; 2011. [cited 2021 Jan 19]. Available from: http://arks.princeton.edu/ark:/88435/dsp01b2773v701.

Council of Science Editors:

Sironi L. Particle Acceleration and Nonthermal Emission in Relativistic Astrophysical Shocks . [Doctoral Dissertation]. Princeton University; 2011. Available from: http://arks.princeton.edu/ark:/88435/dsp01b2773v701

University of New Mexico

12. Linford, Justin D. Parsec-scale properties of gamma-ray bright blazars.

Degree: Physics & Astronomy, 2013, University of New Mexico

URL: http://hdl.handle.net/1928/22052

► The parsec-scale radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been investigated using observations… (more)

▼ The parsec-scale radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been investigated using observations with the Very Long Baseline Array (VLBA). Comparisons between LAT and non-LAT detected samples were made using both archival and contemporaneous data. In total, 244 sources were used in the LAT-detected sample. This very large, radio flux-limited sample of active galactic nuclei (AGN) provides insights into the mechanism that produces strong gamma-ray emission. It has been found that LAT-detected BL Lac objects are very similar to the non-LAT BL Lac objects in most properties, although LAT BL Lac objects may have longer jets. The LAT flat spectrum radio quasars (FSRQs) are significantly different from non-LAT FSRQs and are likely extreme members of the FSRQ population. Archival radio data indicated that there was no significant correlation between radio flux density and gamma-ray flux, especially at lower flux levels. However, contemporaneous observations showed a strong correlation. Most of the differences between the LAT and non-LAT populations are related to the cores of the sources, indicating that the gamma-ray emission may originate near the base of the jets (i.e., within a few pc of the central engine). There is some indication that LAT-detected sources may have larger jet opening angles than the non-LAT sources. Strong core polarization is significantly more common among the LAT sources, suggesting that gamma-ray emission is related to strong, uniform magnetic fields at the base of the jets of the blazars. Observations of sources in two epochs indicate that core fractional polarization was higher when the objects were detected by the LAT. The low-synchrotron peaked (LSP) BL Lac object sample shows indications of contamination by FSRQs which happen to have undetectable emission lines. There is evidence that the LSP BL Lac objects are more strongly beamed than the rest of the BL Lac object population. Advisors/Committee Members: Taylor, Gregory, Rand, Richard, Loomba, Dinesh, Gilmore, Mark.

Subjects/Keywords: BL Lacertae objects; Active galactic nuclei; Quasars; Astrophysical jets; Gamma ray astronomy.

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

APA (6^th Edition):

Linford, J. D. (2013). Parsec-scale properties of gamma-ray bright blazars. (Doctoral Dissertation). University of New Mexico. Retrieved from http://hdl.handle.net/1928/22052

Chicago Manual of Style (16^th Edition):

Linford, Justin D. “Parsec-scale properties of gamma-ray bright blazars.” 2013. Doctoral Dissertation, University of New Mexico. Accessed January 19, 2021. http://hdl.handle.net/1928/22052.

MLA Handbook (7^th Edition):

Linford, Justin D. “Parsec-scale properties of gamma-ray bright blazars.” 2013. Web. 19 Jan 2021.

Vancouver:

Linford JD. Parsec-scale properties of gamma-ray bright blazars. [Internet] [Doctoral dissertation]. University of New Mexico; 2013. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/1928/22052.

Council of Science Editors:

Linford JD. Parsec-scale properties of gamma-ray bright blazars. [Doctoral Dissertation]. University of New Mexico; 2013. Available from: http://hdl.handle.net/1928/22052

13. Zefi, Floriana. Gamma-ray flux variation studies from the blazar B2 1215+30 with the Fermi-LAT and the Crab Nebula with the H.E.S.S. experiment : Étude de la variabilité temporelle de l'émission gamma du blazar B2 1215 + 30 avec Fermi-LAT et de la Nébuleuse du Crabe avec le réseau de télescopes H.E.S.S.

Degree: Docteur es, Astroparticules et cosmologie, 2017, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2017SACLS587

►

Les expériences actuelles en astronomie gamma sont le satellite Fermi-LAT et les expériences au sol tel que H.E.S.S., VERITAS et MAGIC. La surveillance des sources… (more)

▼

Les expériences actuelles en astronomie gamma sont le satellite Fermi-LAT et les expériences au sol tel que H.E.S.S., VERITAS et MAGIC. La surveillance des sources d’énergie très élevées indique une physique diversifiée. Afin d’étudier la forme la plus énergétique de radiation et les phénomènes les plus violents qui se déroulent dans l’Univers, l’analyse des sources individuelles est importante. Les BL Lac, un type de galaxie active, constituent la classe de source extragalactique la plus abondante détecté dans les énergies du GeV au TeV, tandis que le nébuleuses de vent de Pulsar sont la classe la plus peuplée dans le plan galactique. Ces deux types de sources ont des émissions variables de rayons gamma.Dans cette thèse, la variabilité de l'objet BL Lac B2 1215 + 30 est étudiée avec les données du satellite Fermi-LAT. Une grande variation de flux, détectée par Fermi-LAT en février 2014, est simultanée avec un éruption très lumineux observé au TeV par l'expérience VERITAS. En collaboration avec la collaboration VERITAS, la variabilité du flux de rayons gamma a été utilisée pour établir des contraintes sur la taille de la région d'émission et sur le facteur Doppler. La variabilité à long terme, en utilisant près de neuf ans de données de Fermi-LAT de 100 MeV jusqu'à 500 GeV, a permis de détecter plusieurs flares. L'étude de la variabilité du flux indique un comportement quasi périodique avec une période de jours.Ensuite, la variabilité du flux de l’un des objets les plus étudié, la Nébuleuse du Crabe, au TeV est étudiée avec dix ans d'observation de l'expérience H.E.S.S. Le spectre de la nébuleuse du crabe est mesuré de 280 GeV jusqu'à 62 TeV. Ceci est la première mesure qui s'étend à ces très hautes énergies. Considérée comme une “chandelle standard” en astronomie gamma, la nébuleuse du crabe est une source utilisée pour l'étalonnage et l'étude des instruments. L’observation de variations du flux au GeV par le satellite Fermi-LAT a par conséquent été une découverte inattendue. Ces variations de flux au GeV ont motivé la recherche de variations de flux au TeV en utilisant les données de l'expérience H.E.S.S. La position de la nébuleuse de crabe dans l'hémisphère nord et la localisation de H.E.S.S. en Namibie rendent cette enquête complexe en raison des importantes erreurs systématiques introduites par des conditions d'observation non optimales. Le travail sur la nébuleuse du crabe montre que la prise en compte de la transparence atmosphérique pour l'étude de l'évolution du flux avec le temps résulte en une réduction des effets systématiques. Aucune variation de flux n'a été observée à des énergies supérieures à 1 TeV dans les données de H.E.S.S. I. Une autre variation de flux au GeV signalée par le Fermi-LAT en octobre 2016 par télégramme astronomique, a été étudiée avec H.E.S.S. II. Cette analyse a montré que le GeV éruption a duré pendant un mois, et le flux avec H.E.S.S. a une variance excessive de 15 %. Cela devrait être comparé à l'incertitude systématique de 20 % fréquemment citée par H.E.S.S.

The current…

Advisors/Committee Members: Naurois, Mathieu de (thesis director).

Subjects/Keywords: Astronomie gamma; Nébuleuse du Crabe; B2 1215+30; Nébuleuse du vent pulsar; Noyaux actifs de galaxies; Blazars; Variabilité du flux; H.E.S.S. expérience; Satellite Fermi-LAT; Gamma-ray astronomy; Crab Nebula; B2 1215+30; Pulsar wind nebula; Active galactic nuclei; Blazar; Gamma-ray flux variability; H.E.S.S. experiment; Fermi-LAT satellite

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

APA (6^th Edition):

Zefi, F. (2017). Gamma-ray flux variation studies from the blazar B2 1215+30 with the Fermi-LAT and the Crab Nebula with the H.E.S.S. experiment : Étude de la variabilité temporelle de l'émission gamma du blazar B2 1215 + 30 avec Fermi-LAT et de la Nébuleuse du Crabe avec le réseau de télescopes H.E.S.S. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2017SACLS587

Chicago Manual of Style (16^th Edition):

Zefi, Floriana. “Gamma-ray flux variation studies from the blazar B2 1215+30 with the Fermi-LAT and the Crab Nebula with the H.E.S.S. experiment : Étude de la variabilité temporelle de l'émission gamma du blazar B2 1215 + 30 avec Fermi-LAT et de la Nébuleuse du Crabe avec le réseau de télescopes H.E.S.S.” 2017. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 19, 2021. http://www.theses.fr/2017SACLS587.

MLA Handbook (7^th Edition):

Zefi, Floriana. “Gamma-ray flux variation studies from the blazar B2 1215+30 with the Fermi-LAT and the Crab Nebula with the H.E.S.S. experiment : Étude de la variabilité temporelle de l'émission gamma du blazar B2 1215 + 30 avec Fermi-LAT et de la Nébuleuse du Crabe avec le réseau de télescopes H.E.S.S.” 2017. Web. 19 Jan 2021.

Vancouver:

Zefi F. Gamma-ray flux variation studies from the blazar B2 1215+30 with the Fermi-LAT and the Crab Nebula with the H.E.S.S. experiment : Étude de la variabilité temporelle de l'émission gamma du blazar B2 1215 + 30 avec Fermi-LAT et de la Nébuleuse du Crabe avec le réseau de télescopes H.E.S.S. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2017. [cited 2021 Jan 19]. Available from: http://www.theses.fr/2017SACLS587.

Council of Science Editors:

Zefi F. Gamma-ray flux variation studies from the blazar B2 1215+30 with the Fermi-LAT and the Crab Nebula with the H.E.S.S. experiment : Étude de la variabilité temporelle de l'émission gamma du blazar B2 1215 + 30 avec Fermi-LAT et de la Nébuleuse du Crabe avec le réseau de télescopes H.E.S.S. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2017. Available from: http://www.theses.fr/2017SACLS587

George Mason University

14. Secrest, Nathan. Supermassive Black Holes in Bulgeless and Dwarf Galaxies: A Multi-Wavelength Investigation .

Degree: 2014, George Mason University

URL: http://hdl.handle.net/1920/9180

► Supermassive black holes (SMBHs) are now understood to reside at the centers of nearly all major galaxies in the Universe. From studies of high-redshift quasars,… (more)

▼ Supermassive black holes (SMBHs) are now understood to reside at the centers of nearly all major galaxies in the Universe. From studies of high-redshift quasars, we understand that SMBHs formed very early in the Universe's history, and well-studied correlations between other properties of galaxies, such as their morphologies, star formation rate, and merger history, with their central SMBH shows that SMBHs played a key role in the evolution of galaxies. The fact that the post-Big Bang Universe was extremely uniform and homogeneous presents a major mystery: How did SMBHs millions to billions of times as massive as the Sun form in such a short time? Given the theoretical limit at which a black hole can accrete material, it is not plausible that SMBHs could have formed through the conventional route: the end stage of the lifecycle of a massive star. Rather, there are two major theories for the formation of SMBHs, each with its own prediction for the black hole mass distribution and occupation fraction in the local Universe. Understanding this mass distribution and occupation fraction is therefore imperative to understanding the formation of SMBHs, the quasars that reveal their presence in the early Universe, and ultimately the evolution of galaxies to the present day. While large SMBHs in major, bulge-dominated galaxies are relatively easy to detect and characterize, this population of SMBHs is understood to have been built up largely through black hole merger events that erase any information about the progenitor black holes' masses. We must therefore search for SMBHs in late-type, bulgeless, and dwarf galaxies, which are much more likely to have had a relatively quiet, merger-free history, in order to glimpse the properties of the `seed' black holes that led to the buildup of SMBHs during the earliest epoch of the Universe. In this thesis, I will discuss my contributions to the understanding of this question, as well as what questions remain to be answered and the future of research in this field. Advisors/Committee Members: Satyapal, Shobita (advisor).

Subjects/Keywords: Astrophysics; Astronomy; Physics; active galactic nuclei; black holes; extragalactic; galaxies; infrared astronomy; X-ray astronomy

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

APA (6^th Edition):

Secrest, N. (2014). Supermassive Black Holes in Bulgeless and Dwarf Galaxies: A Multi-Wavelength Investigation . (Thesis). George Mason University. Retrieved from http://hdl.handle.net/1920/9180

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):

Secrest, Nathan. “Supermassive Black Holes in Bulgeless and Dwarf Galaxies: A Multi-Wavelength Investigation .” 2014. Thesis, George Mason University. Accessed January 19, 2021. http://hdl.handle.net/1920/9180.

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

MLA Handbook (7^th Edition):

Secrest, Nathan. “Supermassive Black Holes in Bulgeless and Dwarf Galaxies: A Multi-Wavelength Investigation .” 2014. Web. 19 Jan 2021.

Vancouver:

Secrest N. Supermassive Black Holes in Bulgeless and Dwarf Galaxies: A Multi-Wavelength Investigation . [Internet] [Thesis]. George Mason University; 2014. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/1920/9180.

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

Council of Science Editors:

Secrest N. Supermassive Black Holes in Bulgeless and Dwarf Galaxies: A Multi-Wavelength Investigation . [Thesis]. George Mason University; 2014. Available from: http://hdl.handle.net/1920/9180

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

University of Oxford

15. Potter, William J. Black hole jets, accretion discs and dark energy.

Degree: PhD, 2013, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:e286380b-f2ab-4def-bcc4-32c191a3d76d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.629508

► Black hole jets and accretion discs are the most extreme objects in modern astrophysics whilst dark energy is undoubtedly the most mysterious. This thesis focuses… (more)

Subjects/Keywords: 523.8; Astrophysics (theoretical); Astrophysics; Theoretical physics; Black holes; blazars; accretion discs; dark energy; cosmology; active galactic nuclei; black hole jets

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APA (6^th Edition):

Potter, W. J. (2013). Black hole jets, accretion discs and dark energy. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:e286380b-f2ab-4def-bcc4-32c191a3d76d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.629508

Chicago Manual of Style (16^th Edition):

Potter, William J. “Black hole jets, accretion discs and dark energy.” 2013. Doctoral Dissertation, University of Oxford. Accessed January 19, 2021. http://ora.ox.ac.uk/objects/uuid:e286380b-f2ab-4def-bcc4-32c191a3d76d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.629508.

MLA Handbook (7^th Edition):

Potter, William J. “Black hole jets, accretion discs and dark energy.” 2013. Web. 19 Jan 2021.

Vancouver:

Potter WJ. Black hole jets, accretion discs and dark energy. [Internet] [Doctoral dissertation]. University of Oxford; 2013. [cited 2021 Jan 19]. Available from: http://ora.ox.ac.uk/objects/uuid:e286380b-f2ab-4def-bcc4-32c191a3d76d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.629508.

Council of Science Editors:

Potter WJ. Black hole jets, accretion discs and dark energy. [Doctoral Dissertation]. University of Oxford; 2013. Available from: http://ora.ox.ac.uk/objects/uuid:e286380b-f2ab-4def-bcc4-32c191a3d76d ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.629508

Penn State University

16. Yang, Guang. What drives the growth of black holes?.

Degree: 2019, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/16198gxy909

► There are supermassive black holes (SMBHs) in the centers of most massive galaxies. Observations of nearby systems have found that SMBH masses (M_BH ) are… (more)

Subjects/Keywords: X-ray; active galactic nucleus; black hole-galaxy coevolution; photometric redshift; AGN variability; extragalactic transient

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APA (6^th Edition):

Yang, G. (2019). What drives the growth of black holes?. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/16198gxy909

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):

Yang, Guang. “What drives the growth of black holes?.” 2019. Thesis, Penn State University. Accessed January 19, 2021. https://submit-etda.libraries.psu.edu/catalog/16198gxy909.

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

MLA Handbook (7^th Edition):

Yang, Guang. “What drives the growth of black holes?.” 2019. Web. 19 Jan 2021.

Vancouver:

Yang G. What drives the growth of black holes?. [Internet] [Thesis]. Penn State University; 2019. [cited 2021 Jan 19]. Available from: https://submit-etda.libraries.psu.edu/catalog/16198gxy909.

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

Council of Science Editors:

Yang G. What drives the growth of black holes?. [Thesis]. Penn State University; 2019. Available from: https://submit-etda.libraries.psu.edu/catalog/16198gxy909

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

University of Canterbury

17. Bastin, Fane Troy. A multiwavelength investigation of blazar-type active galactic nuclei.

Degree: MS, Physics, 2013, University of Canterbury

URL: http://dx.doi.org/10.26021/7686

► A multiwavelength investigation is conducted for nineteen blazar-type active galactic nuclei. Studies of variability timescales and flux duty cycles are performed at x- and gamma-rays… (more)

Subjects/Keywords: x-ray; gamma-ray; AGN; active galaxies; blazar; blazars; multiwavelength

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APA (6^th Edition):

Bastin, F. T. (2013). A multiwavelength investigation of blazar-type active galactic nuclei. (Masters Thesis). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/7686

Chicago Manual of Style (16^th Edition):

Bastin, Fane Troy. “A multiwavelength investigation of blazar-type active galactic nuclei.” 2013. Masters Thesis, University of Canterbury. Accessed January 19, 2021. http://dx.doi.org/10.26021/7686.

MLA Handbook (7^th Edition):

Bastin, Fane Troy. “A multiwavelength investigation of blazar-type active galactic nuclei.” 2013. Web. 19 Jan 2021.

Vancouver:

Bastin FT. A multiwavelength investigation of blazar-type active galactic nuclei. [Internet] [Masters thesis]. University of Canterbury; 2013. [cited 2021 Jan 19]. Available from: http://dx.doi.org/10.26021/7686.

Council of Science Editors:

Bastin FT. A multiwavelength investigation of blazar-type active galactic nuclei. [Masters Thesis]. University of Canterbury; 2013. Available from: http://dx.doi.org/10.26021/7686

University of Oxford

18. De Franco, Andrea. Development of a camera for Tera-electron Volt gamma-ray astronomy.

Degree: PhD, 2016, University of Oxford

URL: https://ora.ox.ac.uk/objects/uuid:bfa00ea0-3be1-455c-9f82-3429e4bef0da ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730218

► In this thesis I describe the development of a compact camera for ground-based multi TeV gamma-ray astronomy, using the Imaging Atmospheric Cherenkov Telescope (IACT) technique.… (more)

▼ In this thesis I describe the development of a compact camera for ground-based multi TeV gamma-ray astronomy, using the Imaging Atmospheric Cherenkov Telescope (IACT) technique. The camera is based on multi-anode photomultipliers (MAPM) and is designed for use on the Gamma Cherenkov Telescope (GCT), which is proposed to be part of the Small Size Telescope (SST) array of the Cherenkov Telescope Array (CTA). GCT achieves high performance with a compact and cost efficient design via a Schwarzschild-Couder (SC) dual-mirror optical system. The GCT optical design allows the use of a compact camera of diameter roughly 0.5 m. The curved focal plane is equipped with 32 tiles of 64-pixels MAPM for a total of 2048 pixels of ~0.2° angular size, resulting in a field of view of ~9°. The GCT camera is designed to record the flashes of Cherenkov light from electromagnetic cascades, which last only a few tens of nanoseconds. I give a detailed description of the design, the challenges encountered during testing in the lab, and the performance of the most critical components. I give details on the custom front-end electronics modules that provide the required fast electronics, facilitating sampling and digitization, as well as first level of triggering. The camera-level triggering system is a custom backplane, developed to reject spurious triggers on the night sky background, which typically is of the order of few tens of millions of photons per pixel per second. This is to be compared with the rate of the astrophysical signal, which is of the order of few hundreds of events per second at the relevant energies. Additionally I provide a detailed description of all the software needed for the data acquisition and control of the camera, from the very low level drivers to high level and user friendly processes. I follow the commissioning of the camera, from the individual core components to the integration of the system. I then describe the integration of the camera on the GCT prototype telescope structure, and the achievement of "first light", validating for the first time the full proof-of-concept of an IACT with SC optics. I also report a study I performed on expectations for an extragalactic survey for blazars with CTA. The cumulative source count distribution of blazars is presented, including implications from two different phenomena: axion-like particle (ALP) to gamma-ray oscillations in the intergalactic magnetic field, and secondary gamma rays from hadronic origins. I conclude that a shallow and wide survey will provide the best science return for CTA, that the impact of ALP is modest and that the secondary mechanism of gamma-ray production would allow detection of blazars up to redshift of 1 in the multi-TeV energy band.

Subjects/Keywords: 522; Gamma ray astronomy – Instruments; Active Galactic Nuclei; Gamma ray Cherenkov Telescope (GCT); High energy gamma ray; Axion like particle; Cherenkov Telescope Array (CTA)

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APA (6^th Edition):

De Franco, A. (2016). Development of a camera for Tera-electron Volt gamma-ray astronomy. (Doctoral Dissertation). University of Oxford. Retrieved from https://ora.ox.ac.uk/objects/uuid:bfa00ea0-3be1-455c-9f82-3429e4bef0da ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730218

Chicago Manual of Style (16^th Edition):

De Franco, Andrea. “Development of a camera for Tera-electron Volt gamma-ray astronomy.” 2016. Doctoral Dissertation, University of Oxford. Accessed January 19, 2021. https://ora.ox.ac.uk/objects/uuid:bfa00ea0-3be1-455c-9f82-3429e4bef0da ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730218.

MLA Handbook (7^th Edition):

De Franco, Andrea. “Development of a camera for Tera-electron Volt gamma-ray astronomy.” 2016. Web. 19 Jan 2021.

Vancouver:

De Franco A. Development of a camera for Tera-electron Volt gamma-ray astronomy. [Internet] [Doctoral dissertation]. University of Oxford; 2016. [cited 2021 Jan 19]. Available from: https://ora.ox.ac.uk/objects/uuid:bfa00ea0-3be1-455c-9f82-3429e4bef0da ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730218.

Council of Science Editors:

De Franco A. Development of a camera for Tera-electron Volt gamma-ray astronomy. [Doctoral Dissertation]. University of Oxford; 2016. Available from: https://ora.ox.ac.uk/objects/uuid:bfa00ea0-3be1-455c-9f82-3429e4bef0da ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730218

Durham University

19. Dickinson, Mark R. Very high energy gamma ray observations of southern hemisphere blazars.

Degree: PhD, 1997, Durham University

URL: http://etheses.dur.ac.uk/4705/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241776

► This thesis is concerned with very high energy γ-ray observations of blazars observable from the southern hemisphere. The data presented were obtained using the recently… (more)

Subjects/Keywords: 523.01; Gamma ray astronomy; Active galactic nuclei

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APA (6^th Edition):

Dickinson, M. R. (1997). Very high energy gamma ray observations of southern hemisphere blazars. (Doctoral Dissertation). Durham University. Retrieved from http://etheses.dur.ac.uk/4705/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241776

Chicago Manual of Style (16^th Edition):

Dickinson, Mark R. “Very high energy gamma ray observations of southern hemisphere blazars.” 1997. Doctoral Dissertation, Durham University. Accessed January 19, 2021. http://etheses.dur.ac.uk/4705/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241776.

MLA Handbook (7^th Edition):

Dickinson, Mark R. “Very high energy gamma ray observations of southern hemisphere blazars.” 1997. Web. 19 Jan 2021.

Vancouver:

Dickinson MR. Very high energy gamma ray observations of southern hemisphere blazars. [Internet] [Doctoral dissertation]. Durham University; 1997. [cited 2021 Jan 19]. Available from: http://etheses.dur.ac.uk/4705/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241776.

Council of Science Editors:

Dickinson MR. Very high energy gamma ray observations of southern hemisphere blazars. [Doctoral Dissertation]. Durham University; 1997. Available from: http://etheses.dur.ac.uk/4705/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241776

Universidad de Cantabria

20. Barquín González, Lorenzo. The search for the most obscured active galactic nuclei with XMM-Newton and Athena: Búsqueda de los núcleos galácticos activos más oscurecidos con XMM-Newton y Athena.

Degree: Máster en Física de Partículas y del Cosmos, 2019, Universidad de Cantabria

URL: http://hdl.handle.net/10902/17864

► ABSTRACT: One of the most important questions in modern astrophysics is the study of the formation and evolution of galaxies throughout the history of the… (more)

▼ ABSTRACT: One of the most important questions in modern astrophysics is the study of the formation and evolution of galaxies throughout the history of the Universe. In the last decades, several pieces of evidence have been found that support a coevolution of galaxies with the supermassive black hole (SMBH) that most of them (maybe every galaxy) have in their centres. Consequently, to make progress in this field it is necessary to understand the properties of these SMBH. Particularly of those in an active phase of growing (increasing their mass) accreting material from the host galaxy. They are the so-called active galactic nuclei (AGN). Of these, the most highly obscured systems are of special interest, since it is believed that during this highly obscured phase the relationship between SMBHs and their hosts was established. The obscuration is caused by a dust and gas structure, the so-called torus. The highly obscured AGN (known as Compton thick (CT)) are lost in optical surveys and, to a lesser extent, in X-ray surveys as the radiation emitted at these frequencies is absorbed. These AGN could be detected in mid-infrared wavelengths, where obscuration effect are less important. However, their study in X-rays is fundamental to determine the obscuration level. There are empirical relations in the literature that relate the mid-infrared and X-ray luminosity of AGN. The first objective of this work is to check whether these relations describe correctly the relation between luminosities for mid-infrared selected AGN samples (as the one used in this work) and to obtain our own relation otherwise. The second objective is to estimate a lower-limit for the obscuration for mid-infrared selected AGN not detected in deep X-ray exposures with the X-ray observatory XMM-Newton. The last objective is to estimate the necessary exposure times for the detection of this kind of objects with the X-ray observatories XMM-Newton and Athena. To accomplish these scientific objectives we have selected a sample in the mid-infrared composed of 91 AGN: 68 detected in X-rays with XMM-Newton, 3 detected in X-rays but with low-quality X-ray spectra and 20 AGN with no X-ray detection. As it is a sample selected in the mid-infrared it is expected to include objects with obscuration levels all over the parameter space. These AGN (23) are our sample of CT candidates. The X-ray undetected AGN and those with low-quality X-ray spectra are expected to be highly obscured or CT. For the undetected AGN we have upper-limit estimated for their X-ray fluxes. For those AGN with low-quality X-ray spectra, we have the observed luminosity (not corrected by obscuration). These measurements will be used to put constrains on the level of obscuration for these sources. First, we obtained the intrinsic X-ray luminosity (corrected by obscuration) of the CT candidates. To do that we check if the empirical relations of the literatura between X-rays and mid-infrared luminosities are valid for mid-infrared selected samples. As previous relations in the literature… Advisors/Committee Members: Mateos Ibáñez, Silvia (advisor), Universidad de Cantabria (other).

Subjects/Keywords: Active galactic nuclei

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APA (6^th Edition):

Barquín González, L. (2019). The search for the most obscured active galactic nuclei with XMM-Newton and Athena: Búsqueda de los núcleos galácticos activos más oscurecidos con XMM-Newton y Athena. (Masters Thesis). Universidad de Cantabria. Retrieved from http://hdl.handle.net/10902/17864

Chicago Manual of Style (16^th Edition):

Barquín González, Lorenzo. “The search for the most obscured active galactic nuclei with XMM-Newton and Athena: Búsqueda de los núcleos galácticos activos más oscurecidos con XMM-Newton y Athena.” 2019. Masters Thesis, Universidad de Cantabria. Accessed January 19, 2021. http://hdl.handle.net/10902/17864.

MLA Handbook (7^th Edition):

Barquín González, Lorenzo. “The search for the most obscured active galactic nuclei with XMM-Newton and Athena: Búsqueda de los núcleos galácticos activos más oscurecidos con XMM-Newton y Athena.” 2019. Web. 19 Jan 2021.

Vancouver:

Barquín González L. The search for the most obscured active galactic nuclei with XMM-Newton and Athena: Búsqueda de los núcleos galácticos activos más oscurecidos con XMM-Newton y Athena. [Internet] [Masters thesis]. Universidad de Cantabria; 2019. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/10902/17864.

Council of Science Editors:

Barquín González L. The search for the most obscured active galactic nuclei with XMM-Newton and Athena: Búsqueda de los núcleos galácticos activos más oscurecidos con XMM-Newton y Athena. [Masters Thesis]. Universidad de Cantabria; 2019. Available from: http://hdl.handle.net/10902/17864

21. Lorentz, Matthias. Caractérisation de la transparence de l'univers aux rayons gamma de très haute énergie avec H.E.S.S. et aspects associés en physique fondamentale et cosmologie : Characterisation of the transparency of the universe to very-high-energy gamma rays with H.E.S.S. and related aspects in fundamental physics and cosmology.

Degree: Docteur es, Astroparticules et cosmologie, 2017, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2017SACLS249

►

La propagation des rayons Ɣ de très haute énergie (E > 100GeV) dans l'univers est affectée par les propriétés du milieu extragalactique. Ces photons à… (more)

▼

La propagation des rayons Ɣ de très haute énergie (E > 100GeV) dans l'univers est affectée par les propriétés du milieu extragalactique. Ces photons à l'échelle du TeV, issus des processus d'accélération de particules dans les noyaux actifs de galaxies, peuvent en effet interagir avec des photons du fond optique et infrarouge qui baignent l'univers et produire des paires d'électrons et de positrons. Ce processus réduit la transparence de l'univers aux rayons Ɣ de très haute énergie mais permet en revanche de sonder les propriétés du milieu extragalactique de façon unique. Dans cette thèse, les données prises par le réseau de télescopes à imagerie Tcherenkov atmosphérique H.E.S.S. sont analysées et utilisées afin de caractériser la transparence de l'univers aux rayons Ɣ de très haute énergie. Une mesure indépendante de la distribution spectrale en énergie du fond cosmologique optique et infrarouge est réalisée à travers l'ajustement des modulations observées dans les spectres en énergie obtenus avec H.E.S.S. pour un échantillon de noyaux actifs de galaxies brillants dans une gamme en redshift 0.03 < z < 0.28. Les résultats obtenus sont compatibles avec les limites inférieures dérivées par comptages de galaxies et ne suggèrent pas d'anomalie de la transparence de l'univers aux rayons Ɣ vis à vis des modèles actuels du fond de lumière extragalactique. Des processus de second ordre affectant la propagation des rayons Ɣ de très haute énergie sont également explorés. Des limites sur une brisure de la symétrie de Lorentz à l'échelle de Planck sont obtenues à partir de l'analyse spectrale du noyau actif Mrk 501 observé dans un état de flux exceptionnel par H.E.S.S. en 2014, à grand angle zénithal. Enfin, des contraintes sur le champ magnétique extragalactique sont dérivées en considérant l'émission Ɣ secondaire attendue à partir de simulations des cascades électromagnétiques initiées lors du processus d'absorption pour le noyau actif distant PG 1553+113 vu par H.E.S.S. et le télescope spatial Fermi. Cette thèse a également été l'occasion d'une participation aux développements de certains aspects de la calibration et de l'analyse des données de H.E.S.S.

The propagation of very high energy Ɣ rays in the universe depends on the properties of the extragalactic medium. Such TeV-scale photons travelling cosmological distances are -emitted through particle acceleration mechanisms in active galaxy nuclei- can interact with the low-energy photons of the extragalactic background light (EBL) and produce electron-positron pairs. This effect reduces the transparency of the universe to very high energy Ɣ rays but it also provides a unique opportunity to probe the properties of the extragalactic medium. In this thesis, data taken with the H.E.S.S. array of Cherenkov telescopes are analyzed and used to characterize the transparency of the universe to very high energy Ɣ rays. A independent measurement of the spectral energy distribution of the EBL with H.E.S.S. is presented. It is obtained by extracting the EBL absorption signal from the…

Advisors/Committee Members: Brun, Pierre (thesis director).

Subjects/Keywords: Astronomie gamma; Noyaux actifs de galaxies; Cosmologie; Fond optique et infrarouge extragalactique; Brisure de l'invariance de Lorentz; Gamma-Ray astronomy; Active galactic nuclei; Cosmology; Extragalactic background light; Lorentz invariance violation

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APA (6^th Edition):

Lorentz, M. (2017). Caractérisation de la transparence de l'univers aux rayons gamma de très haute énergie avec H.E.S.S. et aspects associés en physique fondamentale et cosmologie : Characterisation of the transparency of the universe to very-high-energy gamma rays with H.E.S.S. and related aspects in fundamental physics and cosmology. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2017SACLS249

Chicago Manual of Style (16^th Edition):

Lorentz, Matthias. “Caractérisation de la transparence de l'univers aux rayons gamma de très haute énergie avec H.E.S.S. et aspects associés en physique fondamentale et cosmologie : Characterisation of the transparency of the universe to very-high-energy gamma rays with H.E.S.S. and related aspects in fundamental physics and cosmology.” 2017. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 19, 2021. http://www.theses.fr/2017SACLS249.

MLA Handbook (7^th Edition):

Lorentz, Matthias. “Caractérisation de la transparence de l'univers aux rayons gamma de très haute énergie avec H.E.S.S. et aspects associés en physique fondamentale et cosmologie : Characterisation of the transparency of the universe to very-high-energy gamma rays with H.E.S.S. and related aspects in fundamental physics and cosmology.” 2017. Web. 19 Jan 2021.

Vancouver:

Lorentz M. Caractérisation de la transparence de l'univers aux rayons gamma de très haute énergie avec H.E.S.S. et aspects associés en physique fondamentale et cosmologie : Characterisation of the transparency of the universe to very-high-energy gamma rays with H.E.S.S. and related aspects in fundamental physics and cosmology. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2017. [cited 2021 Jan 19]. Available from: http://www.theses.fr/2017SACLS249.

Council of Science Editors:

Lorentz M. Caractérisation de la transparence de l'univers aux rayons gamma de très haute énergie avec H.E.S.S. et aspects associés en physique fondamentale et cosmologie : Characterisation of the transparency of the universe to very-high-energy gamma rays with H.E.S.S. and related aspects in fundamental physics and cosmology. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2017. Available from: http://www.theses.fr/2017SACLS249

22. Denes Couto, Jullianna. New Insights into AGN Mass Outflows: Detailed Study of the Spectral Properties of NGC 4151.

Degree: 2017, The Catholic University of America

URL: http://hdl.handle.net/1961/cuislandora:64712

► Active Galactic Nuclei (AGNs) exist in a few percent of all massive galaxies. It is believed that AGNs are powered by accretion of matter onto… (more)

▼ Active Galactic Nuclei (AGNs) exist in a few percent of all massive galaxies. It is believed that AGNs are powered by accretion of matter onto a supermassive black hole (SMBH), generating in the process huge amounts of radiation that span the entire electromagnetic spectrum. In turn, this also triggers the so-called AGN Feedback phenomenon, by inducing the formation of accretion disk winds (or outflows) that accelerate highly ionized gas outwards and affect the intergalactic medium of the host galaxy, reducing star formation rates and preventing bulge growth. It has been suggested that a dominant component of mass outflows is observable in the X-rays, and there are a limited number of detailed studies of single objects for which the relation between outflows and power of the central engine can be determined directly.The Seyfert 1.5 galaxy NGC 4151 is a great study candidate, given its proximity (14.077 Mpc, z = 0.0033), X-ray brightness and orientation. Over the past decades, it has been the target of many single and multiwavelength observations, and its heavily absorbed X-ray spectrum and complex absorption features have been extensively stud- ied and characterized. I have investigated the relationship between the long term X-ray spectral variability in and its intrinsic absorption, by comparing our 2014 simultaneous ultraviolet/X-Ray observations taken with Hubble Space Telescope Imaging Spectrometer (STIS) Echelle and Chandra High Energy Transmission Grating Spectrometer (HETGS) with archival observations from Chandra, XMM-Newton and Suzaku. The observations were divided into ”high” and ”low” flux states, with the low states showing strong and unabsorbed extended emission at energies below 2 keV. The X-ray model consists of a broken powerlaw, neutral reflection and two dominant absorption components, a high and a low ionization component, which are present in all epochs.The model fittings suggest that the absorbers are very stable, with the principal changes in the intrinsic absorption resulting from a response to the variable strength of the ionizing continuum. However, the low states show evidence of larger column densities in one or both of the absorbers. Among plausible explanations for the column increase, I discuss the possibility of an expanding/contracting X-ray corona. The higher ionization component is consistent with being part of a magnetohydrodynamic (MHD) wind, while the lower is possibly radiatively driven, which suggests that at a sufficiently large radial distance there could be a break point between MHD-dominated and radiatively driven outflows.The final model of the absorbed continuum was used as input to the analysis of the soft X-ray emission, which arises in an extended medium of several hundred parsecs. There is evidence of at least four components of gas, with different ionization states and different kinematic profiles. I calculated global covering factors, total masses, mass outflow rates and kinetic luminosity estimates for each component. The models results indicate that it is unlikely… Advisors/Committee Members: The Catholic University of America (Degree granting institution), Kraemer, Steven (Thesis advisor), Turner, T. Jane (Committee member), Crenshaw, D. Michael (Committee member), Wiklind, G. Tommy (Committee member).

Subjects/Keywords: Active Galactic Nuclei; NGC 4151; Seyfert galaxies; X-ray

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APA (6^th Edition):

Denes Couto, J. (2017). New Insights into AGN Mass Outflows: Detailed Study of the Spectral Properties of NGC 4151. (Thesis). The Catholic University of America. Retrieved from http://hdl.handle.net/1961/cuislandora:64712

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):

Denes Couto, Jullianna. “New Insights into AGN Mass Outflows: Detailed Study of the Spectral Properties of NGC 4151.” 2017. Thesis, The Catholic University of America. Accessed January 19, 2021. http://hdl.handle.net/1961/cuislandora:64712.

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

MLA Handbook (7^th Edition):

Denes Couto, Jullianna. “New Insights into AGN Mass Outflows: Detailed Study of the Spectral Properties of NGC 4151.” 2017. Web. 19 Jan 2021.

Vancouver:

Denes Couto J. New Insights into AGN Mass Outflows: Detailed Study of the Spectral Properties of NGC 4151. [Internet] [Thesis]. The Catholic University of America; 2017. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/1961/cuislandora:64712.

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

Council of Science Editors:

Denes Couto J. New Insights into AGN Mass Outflows: Detailed Study of the Spectral Properties of NGC 4151. [Thesis]. The Catholic University of America; 2017. Available from: http://hdl.handle.net/1961/cuislandora:64712

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

23. Pancoast, Anna Kathryn. A New Method for Measuring Black Hole Masses in Active Galaxies: Modeling the Broad Line Region Using Reverberation Mapping Data.

Degree: 2015, University of California – eScholarship, University of California

URL: http://www.escholarship.org/uc/item/1713m85k

► Measuring the masses of supermassive black holes in active galactic nuclei (AGN) allows us to trace their evolution over cosmic time and understand how black… (more)

Subjects/Keywords: Physics; Astrophysics; Astronomy; Active galactic nuclei; Black holes; Reverberation mapping

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APA (6^th Edition):

Pancoast, A. K. (2015). A New Method for Measuring Black Hole Masses in Active Galaxies: Modeling the Broad Line Region Using Reverberation Mapping Data. (Thesis). University of California – eScholarship, University of California. Retrieved from http://www.escholarship.org/uc/item/1713m85k

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):

Pancoast, Anna Kathryn. “A New Method for Measuring Black Hole Masses in Active Galaxies: Modeling the Broad Line Region Using Reverberation Mapping Data.” 2015. Thesis, University of California – eScholarship, University of California. Accessed January 19, 2021. http://www.escholarship.org/uc/item/1713m85k.

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

MLA Handbook (7^th Edition):

Pancoast, Anna Kathryn. “A New Method for Measuring Black Hole Masses in Active Galaxies: Modeling the Broad Line Region Using Reverberation Mapping Data.” 2015. Web. 19 Jan 2021.

Vancouver:

Pancoast AK. A New Method for Measuring Black Hole Masses in Active Galaxies: Modeling the Broad Line Region Using Reverberation Mapping Data. [Internet] [Thesis]. University of California – eScholarship, University of California; 2015. [cited 2021 Jan 19]. Available from: http://www.escholarship.org/uc/item/1713m85k.

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

Council of Science Editors:

Pancoast AK. A New Method for Measuring Black Hole Masses in Active Galaxies: Modeling the Broad Line Region Using Reverberation Mapping Data. [Thesis]. University of California – eScholarship, University of California; 2015. Available from: http://www.escholarship.org/uc/item/1713m85k

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

University of Washington

24. Ruan, John Jianfei. The Astrophysics of Active Galactic Nuclei Variability in Large Scale Spectroscopic Surveys.

Degree: PhD, 2017, University of Washington

URL: http://hdl.handle.net/1773/40473

► More than 50 years after the initial discovery of the extragalactic nature of quasi-stellar objects (quasars) by Schmidt (1963), studies of luminous active galactic nuclei… (more)

▼ More than 50 years after the initial discovery of the extragalactic nature of quasi-stellar objects (quasars) by Schmidt (1963), studies of luminous active galactic nuclei (AGN) have revolutionized our understanding of black hole growth across cosmic time, accretion and jet physics, as well as galaxy evolution and cosmology. In the coming decade, these studies will be further fueled by large (a few x10⁶) samples of quasars from massive optical spectroscopic surveys (e.g., from eBOSS and DESI). These spectra will be accompanied by well-sampled photometric light curves from time-domain imaging surveys (e.g., from Pan-STARRS and LSST), enabling discovery of rare objects and new time-domain phenomena. Current spectroscopic and imaging surveys have well-established that nearly all Type 1 quasars are optically variable, although the origin of this variability is still unknown. The primary goal of this thesis is to investigate various AGN variability phenomena in the UV/optical, to understanding their origin. In particular, I investigate the origin of 10-20% flux variability ubiquitously observed in quasars, the apparent change in accretion states observed in ‘transition blazars’, as well as the rapid fading observed in the recently-discovered ‘changing-look quasars’ phenomenon. I also prepare for the science enabled by the large samples of AGN that will be discovered in future time-domain imaging surveys, by characterizing the unique properties of variability-selected AGN. The primary technique I use in this dissertation to probe AGN variability is repeat optical spectroscopy. AGN optical spectra contain a wealth of information about the central engine, encoded in the properties of the emission lines, absorption lines, and continuum emission. Repeat optical spectroscopy can further probe the time-variable nature of these emission components, but this has previously been little explored in comparison to single-epoch spectroscopy. One notable exception in repeat AGN spectroscopy is the well-established reverberation mapping technique of mapping the size of AGN broad line regions; this has lead to the development of black hole mass estimates based on broad Balmer emission line widths in single-epoch spectroscopy. However, these and other studies based on repeat AGN spectroscopy are only available for small samples of a few dozen AGN at low redshifts, due to the expensive nature of repeat spectroscopy for large samples of faint quasars at higher redshifts. The development of multi-object spectrographs now have the ability to do repeat spectroscopy for large numbers of quasars, opening new windows into AGN astrophysics in the time-domain. Surveys dedicated to repeat quasar spectroscopy, including currently in SDSS-IV and in the future in SDSS-V, will fuel the early science results from this dissertation. In this dissertation, I first use SDSS repeat spectroscopy of quasars to quantify the bluer-when-brighter trend of wavelength-dependent quasar spectral variability, and use it to con- strain simple models of quasar… Advisors/Committee Members: Anderson, Scott F. (advisor).

Subjects/Keywords: accretion; active galactic nuclei; black holes; galaxies; quasars; Astronomy; Astrophysics; Astronomy

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

APA (6^th Edition):

Ruan, J. J. (2017). The Astrophysics of Active Galactic Nuclei Variability in Large Scale Spectroscopic Surveys. (Doctoral Dissertation). University of Washington. Retrieved from http://hdl.handle.net/1773/40473

Chicago Manual of Style (16^th Edition):

Ruan, John Jianfei. “The Astrophysics of Active Galactic Nuclei Variability in Large Scale Spectroscopic Surveys.” 2017. Doctoral Dissertation, University of Washington. Accessed January 19, 2021. http://hdl.handle.net/1773/40473.

MLA Handbook (7^th Edition):

Ruan, John Jianfei. “The Astrophysics of Active Galactic Nuclei Variability in Large Scale Spectroscopic Surveys.” 2017. Web. 19 Jan 2021.

Vancouver:

Ruan JJ. The Astrophysics of Active Galactic Nuclei Variability in Large Scale Spectroscopic Surveys. [Internet] [Doctoral dissertation]. University of Washington; 2017. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/1773/40473.

Council of Science Editors:

Ruan JJ. The Astrophysics of Active Galactic Nuclei Variability in Large Scale Spectroscopic Surveys. [Doctoral Dissertation]. University of Washington; 2017. Available from: http://hdl.handle.net/1773/40473

Univerzitet u Beogradu

25. Savić, Đorđe, 1990-, 36808039. Measuring black hole masses in active galactic nuclei using the polarization of broad emission lines: doctoral dissertation.

Degree: Matematički fakultet, 2020, Univerzitet u Beogradu

URL: https://fedorabg.bg.ac.rs/fedora/get/o:21940/bdef:Content/get

►

Астрономиjа - Астрофизика / Astronomy - Astrophysics

Супермасивне црне рупе (СМЦР-е) се налазе у центру готово сваке масивне галаксиjе у свемиру. Већина су неактивне, али… (more)

▼

Астрономиjа - Астрофизика / Astronomy - Astrophysics

Супермасивне црне рупе (СМЦР-е) се налазе у центру готово сваке масивне галаксиjе у свемиру. Већина су неактивне, али када у околини има доста гаса, започеће активна фаза у коjоj се формира активно галактичко jезгро (АГJ). У активноj фази, СМЦР имаjу велики утицаj на еволуциjу галаксиjе коjа садржи АГJ и њеног окружења. Поуздано мерење масе СМЦР jе зато важан задатак савремене астрономиjе. У ту сврху, Афанасиев и Поповић (2015) су недавно предложили методу коjа користи ротациjу позиционог угла поларизационе равни дуж профила широке емисионе линиjе како би детектовали кеплеровско кретање и одредили масу СМЦР-е. Ова метода претпоставља да су широке линиjе емитоване из пљоснатог дисколиког региона са кеплеровским кретањем, док jе главни механизам поларизациjе расеjање на унутрашњем зиду копланарног торуса прашине – тзв. екваториjално расеjање. Циљ тезе jе теориjски испитати могућности ове методе. Извршили смо броjне Монте Карло симулациjе за моделирање екваториjалног расеjања код АГJ-а користећи кˆoд за пренос зрачења stokes (Goosmann & Gaskell 2007). Разматрали смо и утицаj комплексног кретања емисионог региона коjе може бити у форми радиjалног прилива и вертикалног одлива гаса, или услед присуства двоjне супермасивне црне рупе (ДСМЦР-е). Такође, изабрали смо четири добро позната АГJ-а коjа смо посматрали: NGC 4051, NGC 4151, 3C 273 и PG0844+349. Спектрополариметриjа jе урађена користећи SCORPIO спектрограф монтираним на 6-метарском БТА телескопу Специjалне астрофизичке опсерваториjе Руске академиjе наука (САО РАН-а). Моделирали смо сваки од ових АГJ-а користећи податке из литературе и упоредили смо резултате наших модела са посматрачким подацима. Добили смо да се ова метода може користити за независно мерење маса СМЦР-а код АГJ-а. Утицаj прилива и отицања гаса се може игнорисати уколико су њихове брзине мање од брзина кеплеровског кретања. Додатно, када jе расеjаваjући регион близу широколиниjског региона, ова метода не зависи од инклинациjе посматрања. За систем ДСМЦР-е ова метода се не може користити, међутим, добили смо jединствене профиле коjе нису уобичаjени за jедну СМЦР-у, што може бити коришћено за одређивање могућих кандидата за ДСМЦР-е. Процењене масе СМЦР-а за четири посматрана АГJ-а слажу се добро са масама коjе су процењене другим методама, пре свега методом реверберационог мапирања. Метода за независно мерење маса СМЦР-а jе у овом раду теориjски и експериментално проверена, што jе од изузетног значаjа за будућа изстраживања коjа се баве утицаjем СМЦР-а на своjу непосредну околину.

Advisors/Committee Members: Popović, Luka Č., 1964-, 16615783.

Subjects/Keywords: Active Galactic Nuclei; supermassive black holes; polarization; radiative transfer

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

APA (6^th Edition):

Savić, Đorđe, 1990-, 3. (2020). Measuring black hole masses in active galactic nuclei using the polarization of broad emission lines: doctoral dissertation. (Thesis). Univerzitet u Beogradu. Retrieved from https://fedorabg.bg.ac.rs/fedora/get/o:21940/bdef:Content/get

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):

Savić, Đorđe, 1990-, 36808039. “Measuring black hole masses in active galactic nuclei using the polarization of broad emission lines: doctoral dissertation.” 2020. Thesis, Univerzitet u Beogradu. Accessed January 19, 2021. https://fedorabg.bg.ac.rs/fedora/get/o:21940/bdef:Content/get.

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

MLA Handbook (7^th Edition):

Savić, Đorđe, 1990-, 36808039. “Measuring black hole masses in active galactic nuclei using the polarization of broad emission lines: doctoral dissertation.” 2020. Web. 19 Jan 2021.

Vancouver:

Savić, Đorđe, 1990- 3. Measuring black hole masses in active galactic nuclei using the polarization of broad emission lines: doctoral dissertation. [Internet] [Thesis]. Univerzitet u Beogradu; 2020. [cited 2021 Jan 19]. Available from: https://fedorabg.bg.ac.rs/fedora/get/o:21940/bdef:Content/get.

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

Council of Science Editors:

Savić, Đorđe, 1990- 3. Measuring black hole masses in active galactic nuclei using the polarization of broad emission lines: doctoral dissertation. [Thesis]. Univerzitet u Beogradu; 2020. Available from: https://fedorabg.bg.ac.rs/fedora/get/o:21940/bdef:Content/get

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

University of Waterloo

26. Jeter, Britton. Messier 87: A Laboratory for Exploring AGN Variability using the Event Horizon Telescope.

Degree: 2020, University of Waterloo

URL: http://hdl.handle.net/10012/16314

► At a distance of 50 million light years at the heart of the Virgo cluster, lies the giant elliptical galaxy Messier 87. This galaxy has… (more)

▼ At a distance of 50 million light years at the heart of the Virgo cluster, lies the giant elliptical galaxy Messier 87. This galaxy has at its center a brilliant relativistic jet, observable at all wavelengths, and at the jet's base, the black hole M87*. As of April 2017, this black hole was directly imaged by the Event Horizon Telescope (EHT), a network of eight radio telescopes scattered across the globe. These first images of a black hole will let us investigate not only the physics of black holes, but also the formation and launching mechanism of relativistic jets. The jet in M87 is known to exhibit variability on many different time-scales, from weeks to decades, and comparing the images produced by the EHT to models for jet variability will let us learn how relativistic jets are born. Synchrotron spot models have been used to model variability near black holes; the first part of this thesis extends these models by allowing spots to shear and deform in the jet velocity field. Depending on the position of the spot, shearing forces can significantly alter the structure of the spot, producing distinct signals in reconstructed images and light curves. The maximum intensity of the shearing spot can vary by as much as a factor of five depending on the spot azimuthal launch position, but the intensity decay time depends most significantly on the spot radial launch position. Spots launched by a black hole driven jet exhibit distinct arc structures in reconstructed images, and exhibit brighter and shorter-lived enhancements of the light curve. Spots launched by a wind-driven jet have exhibit much simpler structures in the image, and longer-lived light curve enhancements than spots launched by a black hole driven jet. The EHT measured the mass of M87* to be 6.5 × 10⁹ ~M_\odot, consistent with previous mass estimates from stellar kinematics, but inconsistent by up to 2σ with mass estimates made using gas dynamics models of the gas disk at parsec scales. Critical to gas-dynamical modeling is the assumed underlying dynamical state of the gas: that it lies on circular Keplerian orbits, potentially with some additional turbulent pressure support. This is inconsistent with models of the gas flow about low-accretion-rate SMBHs and at odds with observations of the Galactic Center. In the second part of this thesis, I present an extended model for non-Keplerian gas disks and explore their implications for SMBH mass measurements. I show that a larger central black hole with gas experiencing small amounts of sub-Keplerian motion and/or non-trivial disk thicknesses can produce velocity curves similar to models that just contain circular Keplerian motions and a lower black hole mass. These non-Keplerian models are distinguishable from low-mass Keplerian models primarily through measuremnets of the velocity dispersion, wherein non-Keplerian models produce higher and narrower peak dispersions. By combining the existing velocity measurements from \citet{M87gas:13} and the EHT mass estimate, we…

Subjects/Keywords: astrophysics; galaxies; EHT; black holes; relativistic jets; Active Galactic Nuclei

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

APA (6^th Edition):

Jeter, B. (2020). Messier 87: A Laboratory for Exploring AGN Variability using the Event Horizon Telescope. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/16314

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):

Jeter, Britton. “Messier 87: A Laboratory for Exploring AGN Variability using the Event Horizon Telescope.” 2020. Thesis, University of Waterloo. Accessed January 19, 2021. http://hdl.handle.net/10012/16314.

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

MLA Handbook (7^th Edition):

Jeter, Britton. “Messier 87: A Laboratory for Exploring AGN Variability using the Event Horizon Telescope.” 2020. Web. 19 Jan 2021.

Vancouver:

Jeter B. Messier 87: A Laboratory for Exploring AGN Variability using the Event Horizon Telescope. [Internet] [Thesis]. University of Waterloo; 2020. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/10012/16314.

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

Council of Science Editors:

Jeter B. Messier 87: A Laboratory for Exploring AGN Variability using the Event Horizon Telescope. [Thesis]. University of Waterloo; 2020. Available from: http://hdl.handle.net/10012/16314

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

Penn State University

27. Shen, Jiajian. BLACK HOLE-BULGE RELATIONSHIPS IN BROAD-LINE ACTIVE GALACTIC NUCLEI .

Degree: 2008, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/7978

► The formation and evolution of galaxies in the universe is still poorly understood. Possible clues have come recently from studies of the apparent connection between… (more)

Subjects/Keywords: Host Galaxy; Active Galactic Nuclei; Black Hole; Spectral and Imaging decomposition

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APA (6^th Edition):

Shen, J. (2008). BLACK HOLE-BULGE RELATIONSHIPS IN BROAD-LINE ACTIVE GALACTIC NUCLEI . (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/7978

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):

Shen, Jiajian. “BLACK HOLE-BULGE RELATIONSHIPS IN BROAD-LINE ACTIVE GALACTIC NUCLEI .” 2008. Thesis, Penn State University. Accessed January 19, 2021. https://submit-etda.libraries.psu.edu/catalog/7978.

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

MLA Handbook (7^th Edition):

Shen, Jiajian. “BLACK HOLE-BULGE RELATIONSHIPS IN BROAD-LINE ACTIVE GALACTIC NUCLEI .” 2008. Web. 19 Jan 2021.

Vancouver:

Shen J. BLACK HOLE-BULGE RELATIONSHIPS IN BROAD-LINE ACTIVE GALACTIC NUCLEI . [Internet] [Thesis]. Penn State University; 2008. [cited 2021 Jan 19]. Available from: https://submit-etda.libraries.psu.edu/catalog/7978.

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

Council of Science Editors:

Shen J. BLACK HOLE-BULGE RELATIONSHIPS IN BROAD-LINE ACTIVE GALACTIC NUCLEI . [Thesis]. Penn State University; 2008. Available from: https://submit-etda.libraries.psu.edu/catalog/7978

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

Indian Institute of Science

28. Deovrat, *. AGN Feedback in Galaxy Clisters - Controlling Cooling Flows in Galaxy Clusters by Momentum-driven AGN Jets.

Degree: PhD, Faculty of Science, 2019, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/4219

► Synopsis According to the hierarchical structure formation model, massive structures like galaxy clusters are formed due to the gravitational collapse of initial density perturbations and… (more)

▼ Synopsis According to the hierarchical structure formation model, massive structures like galaxy clusters are formed due to the gravitational collapse of initial density perturbations and their subsequent mergers. As the formation of galaxy clusters is driven by gravity, they are expected to follow self-similar profiles for density, temperature, entropy etc (Kaiser 1986). However, observations show that self-similarity assumption is not followed in clusters due to the presence of cooling and other such non-gravitational processes (Markevitch et al. 1998; Ponman et al. 1999). More than a third of galaxy clusters have cooling time of the hot diﬀuse gas in the intra-cluster medium (ICM) in their core smaller than their lifetime (Cavagnolo et al. 2009). As a result, the hot gas in cluster core is expected to cool down catastrophically with total cold gas mass deposition in the core greater than 1012 M⊙ during their lifetime and a star formation rate of several 100 M⊙yr−1. However, lack of observational support of these cooling flow signatures (Peterson et al. 2003) in clusters with short cooling time (cool core clusters) point to the presence of some heating mechanism to compensate the cooling loses and prevent the runway cooling. Among many possible candidates, AGN jets associated with the supermassive black hole present in member central galaxy of the cluster has emerged as the principle heating source (McNamara and Nulsen 2007). Observations show that the energy required to form the structures in the ICM as a result of AGN outbursts, are suﬃcient to overcome the radiative losses of the ICM. However, the details of AGN feedback to control the cooling flow remains sketchy. My thesis is based on numerical study of AGN feedback in galaxy clusters and trying to answer some important questions related to it. In chapter 1, we discuss the process of galaxy cluster formation and how self-similarity arises naturally in such systems. We then discuss the observational evidences of the breaking of self-similarity in galaxy clusters. We look at the early history of X-ray observations of galaxy clusters and the quest to find signatures of cooling flow as predicted by theoretical models. The non-detection of cooling flow signatures like absence of line emissions below 0.5 keV in several cool core clusters gave rise to the possibility of presence of some heating mechanism to control the cooling flow. We discuss the observational evidences pointing to AGN jets being the possible heating source to compensate for the cooling losses of the ICM. We discuss the diﬀerent modes of AGN feedback in galaxy clusters and their role in the evolution of these systems. We finally give a brief history of the numerical work done in the area of AGN feedback in galaxy clusters. This chapter ends with the big questions in AGN feedback model that needed investigation. In chapter 2, using high-resolution 3-D and 2-D (axisymmetric) hydrodynamic simulations in spherical geometry, we study the evolution of cool cluster cores heated by… Advisors/Committee Members: Sharma, Prateek (advisor).

Subjects/Keywords: Galaxy Cluster Formation; AGN Jet; AGN-Driven Turbulence.; Galaxy Clister; Active Galactic Nuclei; Super-massive Black Hole (SMBH); Cool Core Cycles; Physics

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APA (6^th Edition):

Deovrat, *. (2019). AGN Feedback in Galaxy Clisters - Controlling Cooling Flows in Galaxy Clusters by Momentum-driven AGN Jets. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/4219

Chicago Manual of Style (16^th Edition):

Deovrat, *. “AGN Feedback in Galaxy Clisters - Controlling Cooling Flows in Galaxy Clusters by Momentum-driven AGN Jets.” 2019. Doctoral Dissertation, Indian Institute of Science. Accessed January 19, 2021. http://etd.iisc.ac.in/handle/2005/4219.

MLA Handbook (7^th Edition):

Deovrat, *. “AGN Feedback in Galaxy Clisters - Controlling Cooling Flows in Galaxy Clusters by Momentum-driven AGN Jets.” 2019. Web. 19 Jan 2021.

Vancouver:

Deovrat *. AGN Feedback in Galaxy Clisters - Controlling Cooling Flows in Galaxy Clusters by Momentum-driven AGN Jets. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2019. [cited 2021 Jan 19]. Available from: http://etd.iisc.ac.in/handle/2005/4219.

Council of Science Editors:

Deovrat *. AGN Feedback in Galaxy Clisters - Controlling Cooling Flows in Galaxy Clusters by Momentum-driven AGN Jets. [Doctoral Dissertation]. Indian Institute of Science; 2019. Available from: http://etd.iisc.ac.in/handle/2005/4219

29. Becker, Julia K. Neutrinos on the rocks.

Degree: 2007, Technische Universität Dortmund

URL: http://hdl.handle.net/2003/24295

Subjects/Keywords: active galactic nuclei; AGN; astroparticle physics; Astroteilchenphysik; gamma ray burst; GRBs; neutrinos; 530

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

APA (6^th Edition):

Becker, J. K. (2007). Neutrinos on the rocks. (Thesis). Technische Universität Dortmund. Retrieved from http://hdl.handle.net/2003/24295

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):

Becker, Julia K. “Neutrinos on the rocks.” 2007. Thesis, Technische Universität Dortmund. Accessed January 19, 2021. http://hdl.handle.net/2003/24295.

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

MLA Handbook (7^th Edition):

Becker, Julia K. “Neutrinos on the rocks.” 2007. Web. 19 Jan 2021.

Vancouver:

Becker JK. Neutrinos on the rocks. [Internet] [Thesis]. Technische Universität Dortmund; 2007. [cited 2021 Jan 19]. Available from: http://hdl.handle.net/2003/24295.

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

Council of Science Editors:

Becker JK. Neutrinos on the rocks. [Thesis]. Technische Universität Dortmund; 2007. Available from: http://hdl.handle.net/2003/24295

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

30. Becker, Julia K. Neutrinos on the rocks: on the phenomenology of potential astrophysical neutrino sources.

Degree: 2007, Technische Universität Dortmund

URL: http://dx.doi.org/10.17877/DE290R-15959

Subjects/Keywords: neutrinos; astroparticle physics; gamma ray burst; active galactic nuclei; Astroteilchenphysik; AGN; GRBs; 530

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

APA (6^th Edition):

Becker, J. K. (2007). Neutrinos on the rocks: on the phenomenology of potential astrophysical neutrino sources. (Doctoral Dissertation). Technische Universität Dortmund. Retrieved from http://dx.doi.org/10.17877/DE290R-15959

Chicago Manual of Style (16^th Edition):

Becker, Julia K. “Neutrinos on the rocks: on the phenomenology of potential astrophysical neutrino sources.” 2007. Doctoral Dissertation, Technische Universität Dortmund. Accessed January 19, 2021. http://dx.doi.org/10.17877/DE290R-15959.

MLA Handbook (7^th Edition):

Becker, Julia K. “Neutrinos on the rocks: on the phenomenology of potential astrophysical neutrino sources.” 2007. Web. 19 Jan 2021.

Vancouver:

Becker JK. Neutrinos on the rocks: on the phenomenology of potential astrophysical neutrino sources. [Internet] [Doctoral dissertation]. Technische Universität Dortmund; 2007. [cited 2021 Jan 19]. Available from: http://dx.doi.org/10.17877/DE290R-15959.

Council of Science Editors:

Becker JK. Neutrinos on the rocks: on the phenomenology of potential astrophysical neutrino sources. [Doctoral Dissertation]. Technische Universität Dortmund; 2007. Available from: http://dx.doi.org/10.17877/DE290R-15959

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Open Access Theses and Dissertations