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You searched for +publisher:"Universidade Nova" +contributor:("Indelicato, Paul"). Showing records 1 – 3 of 3 total matches.

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Universidade Nova

1. Machado, Jorge Felizardo Dias Cunha. High precision tests of QED Measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions.

Degree: 2018, Universidade Nova

This work aims to provide insight on Bound-State Quantum-Electrodynamics (BSQED) by experimental fundamentals high-precision tests in exotic states of matter. Although BSQED and the relativistic many-body problem have been undergoing important progress, there are still some issues that require the increase of the number and accuracy of experimental fundamental tests. The first part of this work was done within the framework of the recent experiment in muonic helium ions ( 4He+ and 3He+) by the CREMA collaboration. This experiment, aims to provide new accurate values for the root-mean-square (rms) charge radii of the helium isotopes nuclei that are extracted from the measurement of the Lamb Shift, i.e., the measurement of the energy difference between the 2S 2P states. With the goal of measuring the transition energies with an accuracy of at least 50 ppm, the rms charge radii of the helium isotopes will be determined with an uncertainty of 0.03%, a factor of ten more precise than previous results obtained from electron scattering. The second part of this work aims the high-precision measurement of x-ray transitions in Highly-Charged Ions (HCI) using a Double-Crystal Spectrometer (DCS). These ions were produced in the plasma of an Electron-Cyclotron Resonance Ion Source (ECRIS). This kind of spectrometer is able not only to provide high-precision measurements but also reference-free measurements, without reference to any theoretical or experimental energy. Four transitions energies from n = 2!n = 1 have been measured in an argon plasma in three different charge states, He-, Be- and Li-like, with an accuracy of better than 3 ppm. Besides the energies, the natural width of each transition has also been experimentally obtained. The obtained results are in excellent agreement with the most recent theoretical calculations. Advisors/Committee Members: Santos, José, Indelicato, Paul.

Subjects/Keywords: Muonic atoms (ions); Lamb shift; Laser spectroscopy; Relativistic and QED effects; ECRIS; HCI; Domínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e Tecnologias

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

APA (6th Edition):

Machado, J. F. D. C. (2018). High precision tests of QED Measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions. (Thesis). Universidade Nova. Retrieved from https://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/33710

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

Chicago Manual of Style (16th Edition):

Machado, Jorge Felizardo Dias Cunha. “High precision tests of QED Measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions.” 2018. Thesis, Universidade Nova. Accessed October 25, 2020. https://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/33710.

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

MLA Handbook (7th Edition):

Machado, Jorge Felizardo Dias Cunha. “High precision tests of QED Measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions.” 2018. Web. 25 Oct 2020.

Vancouver:

Machado JFDC. High precision tests of QED Measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions. [Internet] [Thesis]. Universidade Nova; 2018. [cited 2020 Oct 25]. Available from: https://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/33710.

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

Council of Science Editors:

Machado JFDC. High precision tests of QED Measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions. [Thesis]. Universidade Nova; 2018. Available from: https://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/33710

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


Universidade Nova

2. Amaro, Pedro Manuel Duarte Gonçalves. Study of forbidden transitions in atomic systems.

Degree: 2011, Universidade Nova

A Thesis submitted for the co-tutelle degree of Doctor in Physics at Universidade Nova de Lisboa and Université Pierre et Marie Curie

One active topic in Atomic Physics is the study of highly charged ions (HCI). These physical systems have a strong Coulomb field that provides a unique opportunity to investigate and validate relativistic, Quantum ElectroDynamics (QED), and many-body e ects. Moreover, fundamental test on symmetries and parity violation gives clues to the physics beyond the Standard Model. Thus, nowadays, a primary goal of Atomic Physics is the existence of precise experimental data and accurate theoretical calculations for these systems. In this thesis I focus on the investigation of forbidden radiative transitions in HCI. The main emphasis of this work is on atomic transitions, in which the selection rules forbids the emission of electric dipole photons. In this special type of radiative transition, the electron decays mainly through the emission of a single magnetic dipole photon, or two electric dipole photons. Both types of decay are investigated either experimentally or theoretically. The two-photon decay is only theoretically investigated, using a full relativistic formalism,in HCI with one or two electrons. Several physical e ects in the two photon decay, such as resonances, the Dirac’s negative continuum or angular correlations are considered. Related with the decay, two-photon excitation is also investigated. According to these evaluations, I stress the importance of relativistic and nondipolar e ects. Moreover, a new approach based on the B-polynomials basis set is employed on two-photon transitions. The second part of the work is devoted to the precise measurement of transitions in highly charged Ar with two to four electrons. For that matter, I describe the technical features of a double crystal spectrometer used to perform those measurements in HCI for the first time. This kind of spectrometer is able to perform absolute and precise measurements with an accuracy never achieved in these systems, which enables a comparison with recent QED calculations. I describe a Monte-Carlo code developed with the purpose of studying several systematic errors, as well as testing the various methods of retrieving physical quantities from raw data. Finally, I present the first absolute 2 ppm measurements on HCI with this spectrometer, paying special attention on the forbidden magnetic dipole transition in He-like Ar.

Accõess Integradas Luso-Alem˜as (Contract no A-19/09); Fundação de Ciências e Tecnologia (FCT)- contract SFRH/BD/37404/2007 ; Programa Operacional Potencial Humano (POPH/FSE) and European Union social fund

Advisors/Committee Members: José, Santos, Indelicato, Paul.

Subjects/Keywords: Forbidden transitions; HCI; QED; Multi-photon processes; ECRIS; Xray spectroscopy

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

APA (6th Edition):

Amaro, P. M. D. G. (2011). Study of forbidden transitions in atomic systems. (Thesis). Universidade Nova. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/6916

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

Chicago Manual of Style (16th Edition):

Amaro, Pedro Manuel Duarte Gonçalves. “Study of forbidden transitions in atomic systems.” 2011. Thesis, Universidade Nova. Accessed October 25, 2020. http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/6916.

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

MLA Handbook (7th Edition):

Amaro, Pedro Manuel Duarte Gonçalves. “Study of forbidden transitions in atomic systems.” 2011. Web. 25 Oct 2020.

Vancouver:

Amaro PMDG. Study of forbidden transitions in atomic systems. [Internet] [Thesis]. Universidade Nova; 2011. [cited 2020 Oct 25]. Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/6916.

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

Council of Science Editors:

Amaro PMDG. Study of forbidden transitions in atomic systems. [Thesis]. Universidade Nova; 2011. Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/6916

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

3. Machado, Jorge Felizardo Dias Cunha. High precision tests of QED : measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions : Essais de haute précision du QED : mesures de la particule alpha et de la racine moyenne des rayons de charge de l'hélium et les énergies de transition en ions fortement chargés.

Degree: Docteur es, Physique, 2018, Sorbonne université; Universidade nova de Lisboa. Faculdade de ciências e tecnologia (Lisboa, Portugal)

Ce travail vise à contribuer à l’amélioration de notre connaissance de l’électrodynamique quantique des états liés, par des mesures de haute précision dans des états exotiques de la matière. Bien que notre connaissance de l’électrodynamique quantique des états liés et du problème relativiste à plusieurs corps aient fait des progrès importants ces dernières années, il reste des questions fondamentales dont la résolution nécessite d’augmenter le nombre et la précision des tests expérimentaux. La première partie de ce travail a été réalisée dans le cadre de l’expérience récente sur les ions muoniques d’hélium (μ4He+ et μ3He+) conduite par la collaboration CREMA. Cette expérience vise à fournir de nouvelles valeurs précises pour les rayons de charge moyens des noyaux des isotopes stables de l’hélium. Ces valeurs sont extraites de la mesure du déplacement de Lamb, c’est-à-dire, de la mesure de la différence d’énergie entre les États 2S − 2P. Une mesure des énergies de transition d’une précision d’au moins 50 ppm, permet de déterminer les rayons de charge des noyaux des isotopes d’hélium avec une incertitude de 0,03%, dix fois plus précise que les résultats précédents obtenus à partir de la diffusion d’électrons. La deuxième partie de ce travail a été de réaliser des mesures de haute précision de transitions de rayons X dans des ions fortement chargés, à l’aide d’un spectromètre à double cristal plan. Ces ions étaient produits dans le plasma d’une source d’ions de type ECRIS (electron-cyclotron resonance ion source). Le spectromètre utilisé est non seulement capable de fournir des mesures de haute précision, mais aussi des mesures sans référence à des énergies de transition théorique ou expérimentales. Quatre énergies de transition de n = 2 → n = 1 ont été mesurées pour des ions d’argon de trois états de charge différents, héliumoïde, lithiumoïde et berylliumoïde, avec une précision meilleure que 3 ppm. La largeur naturelle de chaque raie a également été obtenue expérimentalement. Les résultats trouvés sont en excellent accord avec les calculs théoriques les plus récents.

This work aims to provide insight on Bound-State Quantum-Electrodynamics (BSQED) by experimental fundamentals high-precision tests in exotic states of matter. Although BSQED and the relativistic many-body problem have been undergoing important progress, there are still some issues that require the increase of the number and accuracy of experimental fundamental tests. The first part of this work was done within the framework of the recent experiment in muonic helium ions (μ4He+ and μ3He+) by the CREMA collaboration. This experiment, aims to provide new accurate values for the root-mean-square (rms) charge radii of the helium isotopes nuclei that are extracted from the measurement of the Lamb Shift, i.e., the measurement of the energy difference between the 2S − 2P states. With the goal of measuring the transition energies with an accuracy of at least 50 ppm, the rms…

Advisors/Committee Members: Indelicato, Paul (thesis director), Santos, José Paulo (thesis director).

Subjects/Keywords: Atomes muoniques (ions); Spectroscopie laser; Effets relativistes et QED; Ions fortement chargés; Spectroscopie aux rayons X sans référence; Lamb shift; Muonic atoms (ions); Reference-free X-ray spectroscopy; Electro-cyclotron resonance ion source; 530.1433

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

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

APA (6th Edition):

Machado, J. F. D. C. (2018). High precision tests of QED : measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions : Essais de haute précision du QED : mesures de la particule alpha et de la racine moyenne des rayons de charge de l'hélium et les énergies de transition en ions fortement chargés. (Doctoral Dissertation). Sorbonne université; Universidade nova de Lisboa. Faculdade de ciências e tecnologia (Lisboa, Portugal). Retrieved from http://www.theses.fr/2018SORUS016

Chicago Manual of Style (16th Edition):

Machado, Jorge Felizardo Dias Cunha. “High precision tests of QED : measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions : Essais de haute précision du QED : mesures de la particule alpha et de la racine moyenne des rayons de charge de l'hélium et les énergies de transition en ions fortement chargés.” 2018. Doctoral Dissertation, Sorbonne université; Universidade nova de Lisboa. Faculdade de ciências e tecnologia (Lisboa, Portugal). Accessed October 25, 2020. http://www.theses.fr/2018SORUS016.

MLA Handbook (7th Edition):

Machado, Jorge Felizardo Dias Cunha. “High precision tests of QED : measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions : Essais de haute précision du QED : mesures de la particule alpha et de la racine moyenne des rayons de charge de l'hélium et les énergies de transition en ions fortement chargés.” 2018. Web. 25 Oct 2020.

Vancouver:

Machado JFDC. High precision tests of QED : measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions : Essais de haute précision du QED : mesures de la particule alpha et de la racine moyenne des rayons de charge de l'hélium et les énergies de transition en ions fortement chargés. [Internet] [Doctoral dissertation]. Sorbonne université; Universidade nova de Lisboa. Faculdade de ciências e tecnologia (Lisboa, Portugal); 2018. [cited 2020 Oct 25]. Available from: http://www.theses.fr/2018SORUS016.

Council of Science Editors:

Machado JFDC. High precision tests of QED : measurement of the alpha-particle and helion rms charge radius and the transition energies in highly-charged ions : Essais de haute précision du QED : mesures de la particule alpha et de la racine moyenne des rayons de charge de l'hélium et les énergies de transition en ions fortement chargés. [Doctoral Dissertation]. Sorbonne université; Universidade nova de Lisboa. Faculdade de ciências e tecnologia (Lisboa, Portugal); 2018. Available from: http://www.theses.fr/2018SORUS016

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