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Mazzucato, Eddy. "Photoproduction de pions neutres sur le proton au voisinage du seuil." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37607801m.
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Fuchey, E. "Electroproduction de pions neutres dans le Hall A au Jefferson Laboratory." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2010. http://tel.archives-ouvertes.fr/tel-00586093.
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La décennie passée a vu une forte évolution de l'étude de la structure des hadrons par les processus exclusifs, permettant d'accéder à une description plus complète de cette structure. Les processus exclusifs incluent la diffusion Compton profondément virtuelle, ainsi que la production exclusive de mesons à haute énergie. Ce document s'attache particulièrement à ce dernier, et plus particulièrement à la production exclusive de pions neutres. Cette thèse décrit l'analyse des événements en triple coïncidence H(e,e'gamma gamma)X, qui fut un sous produit abondant de l'expérience DVCS qui a eu lieu durant l'automne 2004 dans le Hall A au Jefferson Laboratory, afin d'extraire la section efficace de ep → epπ0 . Cette section efficace a été mesurée à deux valeurs de quadrimoment de tranfert Q2 =1.9 GeV2 et Q2 =2.3 GeV2 . La précision statistique accomplie pour ces mesures est meilleure que 5 %. Le domaine cinématique permet d'étudier l'évolution en Q2 et en W de la section efficace. Ces résultats ont été comparés avec des calculs inspirés de la phénoménologie de Regge, ainsi qu'avec les prédictions du formalisme des distributions de partons généralisées. Une interprétation dans le cadre de la diffusion profondément inélastique semi-inclusive est également discutée.
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Fuchey, Eric. "Electroproduction de pions neutres dans le Hall A au Jefferson Laboratory." Clermont-Ferrand 2, 2010. http://www.theses.fr/2010CLF22037.
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La décennie passée a vu une forte évolution de l'étude de la structure des hadrons par les processus exclusifs, permettant d'accéder à une description plus complète de cette structure. Les processus exclusifs incluent la diffusion Compton profondément virtuelle, ainsi que la production exclusive de mesons à haute énergie. Ce document s'attache particulièrement à ce dernier, et plus particulièrement à la production exclusive de pions neutres. Cette thèse décrit l'analyse des événements en triple H(e,égammagamma)X, qui fut un sous produit abondant de l'expérience DVCS qui a eu lieu durant l'automne 2004 dans le Hall A au Jefferson Laboratory, afin d'extraire la section efficace de ép ->eppi°. Cette section efficace a été mesurée à deux valeurs de quadrimoment de transfert Q2=1. 9GeV2 et Q2=2. 3GeV2. La précision statistique accomplie pour ces mesures est meilleur que 5%. Le domaine cinématique permet d'étudier l'évolution en Q2 et en W de la section. Ces résultats ont été comparés avec des calculs inspirés de la phénoménologie de Regge, ainsi qu'avec les prédictions du formalisme des distributions de partons généralisées. Une interprétation dans le cadre de la diffusion profondément inélastique semi-inclusive est également discutée
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Jammes, Laurent. "Photoproduction de pions neutres au voisinage du seuil sur les noyaux d'hélium 4, de carbone 12 et de calcium 40." Paris 11, 1988. http://www.theses.fr/1988PA112241.
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Nous présentons les résultats d'une mesure de section efficace totale de photo production de pions neutres sur les noyaux d'hélium 4, de carbone et de calcium, dans le domaine d'énergie de photons allant du seuil de réaction à 180 MeV, ainsi que des données prises à 148 MeV sur les noyaux de lithium 6 et de magnésium. Cette expérience a utilisé le faisceau de photons étiquetés obtenu par annihilation en vol des positrons délivrés par l'accélérateur Linéaire de Saclay (A. L. S. ) sur les électrons atomiques d'une cible d'hydrure de lithium. Le pion neutre est identifié par la détection en coïncidence de ses deux photons de désintégration, dans un ensemble de détecteurs en verre au plomb couvrant un grand angle solide. L'expérience sur l'hélium 4 a nécessité l'étude et la réalisation d'une cible cryogénique d'hélium liquide adaptée à la géométrie de l'installation. Un système de filtre a photons, fonctionnant sur le principe d'un spectromètre à paires, permet une mesure précise du flux incident. La détermination de la section efficace repose sur les analyses conjointes et similaires des événements caractéristiques de la création d'un pion ou d'une paire électron-positron, en coïncidence avec la détection d'un photon d'étiquetage. La simulation du fonctionnement du détecteur de pions neutres par une méthode de type Monte-Carlo, permet le calcul de l'efficacité de détection. Les deux calculs dont nous disposons, qui incluent la distorsion de l'onde du pion dans l'état final, sont tous deux en accord avec les données expérimentales, bien que leurs estimations en onde plane diffèrent notablement. Nous essayons de dégager l'origine de cette coïncidence provenant de l'utilisation, par les auteurs, de diverses simplifications cinématiques et de déterminations différentes du potentiel optique. Enfin, par la comparaison des prédictions d'un modèle simple d'approximation d'impulsion avec les sections efficaces expérimentales, nous déduisons pour chaque noyau, une évaluation de l'effet de l'interaction pion-noyau dans l'état final, relativement au carbone.
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Benhabib, Lamia. "Détection de pions neutres dans les collisions proton-proton à l'aide du spectromètre de photons PHOS de l'expérience ALICE auprès du LHC." Nantes, 2009. http://www.theses.fr/2009NANT2116.
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Les collisions d'ions lourds à des énergies ultra-relativistes permettent de créer de la matière nucléaire sous forme de Plasma de Quarks et de Gluons (PQG) puis de l’étudier grâce à de nombreuses observables proposées pour signer sa formation. Ce travail de thèse, en particulier, s’intéresse à la mesure de pions neutres (0) qui représente une sonde importante aussi bien pour la physique des collisions proton-proton que pour celle des collisions noyau-noyau. Dans le premier cas, elle permet de tester la chromodynamique quantique perturbative pQCD, théorie de l'interaction forte, et de contraindre les modèles théoriques. Elle servira ensuite de référence pour déceler des comportements anormaux dans les collisions noyau-noyau. Dédiée aux ions lourds, l'expérience ALICE auprès du collisionneur LHC, permet à l'aide, entre autres, de son spectromètre de photons PHOS, la mesure des 0 grâce à leur canal de désintégration en deux photons (0 ). PHOS couvrira un domaine en impulsion transverse variant de quelques centaines de MeV/c à quelques dizaines de GeV/c. Nous présentons, dans un premier temps, les prédictions théoriques sur la section efficace de production de pions neutres à l’ordre dominant et à l’ordre dominant suivant ainsi que le taux de comptage pour différents scénarios au LHC. Les coefficients correctifs à appliquer pour l’obtention d’un spectre de pions neutres sont ensuite calculés en termes d’acceptance géométrique, d’efficacité de reconstruction et d’efficacité du déclenchement. En outre, cette thèse consacre un chapitre plus technique au calibrage du premier module PHOS. Ceci a permis d’établir la carte des mauvais canauxUltra-relativistic Heavy-Ion Collisions (HIC) allow to create nuclear matter as Quark Gluon Plasma (QGP) and to study it through various observables proposed to highlight its formation, in particular, via measurements of neutral pions (0). The 0 measurement is an important probe for both proton and heavy ion physics. In the former case, it provides an important mean of testing pQCD as well as useful data to constrain current and future theoretical models. It will then serves as a baseline to detect abnormal behaviour in heavy ion collisions. Dedicated to heavy ion physics, the ALICE experiment at Large Hadron Collider, allows the identification of 0 mesons via their decay into two photons (0 ) using the high resolution photon spectrometer (PHOS). PHOS will measure over a wide range of transverse momentum, spanning from hundreds of MeV/c up to several tenths of GeV/c. In order to perform the first 0 spectrum measurement at LHC and compare it to theoretical predictions, an estimation of 0 production cross-section in proton-proton collisions is calculated in a leading order LO and a next-to-leading order (NLO) approximation and presented at a first place. We also discuss the Monte Carlo correction factors to apply for obtaining a realistic 0 spectrum as the geometrical acceptance, the identification efficiency and the trigger efficiency along with the analysis on the invariant mass. The quality of the measurement depends on the performance of PHOS detector. In particular calibration studies on the first PHOS module have also been performed yielding a map of bad channels
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Jammes, Laurent. "Photoproduction de pions neutres au voisinage du seuil sur les noyaux d'hélium-4, de carbone-12 et de calcium-40." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376144715.
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Charbonnier, Yves. "Processus collectifs et individuels de production de particules sous le seuil. Production de pions neutres et mesons dans la reaction ar+ca a 180a mev." Caen, 1997. http://www.theses.fr/1997CAEN2068.
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Ce travail a pour objet l'etude des processus collectifs et de collision nucleon-nucleon individuelle dans la production de particules sous le seuil. Dans ce but, et pour la premiere fois, nous avons simultanement etudie les taux de production des mesons et produits sous le seuil dans la reaction ar+ca a 180a mev. Notre revue des donnees experimentales preexistantes souligne l'interet specifique de ces particules comme sonde de la matiere nucleaire dense et chaude formee au cours des collisions entre ions lourds. Cette experience a ete realisee avec le multidetecteur taps au gsi. Le dispositif experimental et les techniques d'analyse utilisees nous ont permis d'obtenir les multiplicites et les sections efficaces de production de ces mesons. Il s'est avere que la production des mesons est 20 fois plus faibles que celle prevue par la systematique. De facon surprenante, il semble que la loi d'echelle en masse transverse soit encore valide a si faible energie. Nous avons demontre que la plupart des pions observes interagissent avec la matiere nucleaire via l'excitation des resonances. Enfin, nous avons observe que la multiplicite des pions augmente avec le nombre de nucleons participants mais de facon plus marquee pour les pions de grande masse transverse que pour l'ensemble des pions. Ceci est une indication claire que le mecanisme de production des particules tres energetiques, au dela de l'image d'un superposition de collisions de premiere chance, implique des processus collectifs et cooperatifs. Ces resultats ont ete confrontes avec les predictions de deux modeles dynamiques, et d'un modele statistique. Ces modeles sous-estiment fortement les sections efficaces et aucun n'est en mesure de fournir une vision coherente des processus mis en jeu.
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Aphecetche, Laurent. "Mecanismes de production de particules sous le seuil dans la matiere nucleaire froide : production de pions neutres et de photons dans les reactions proton-noyau a 190 mev." Caen, 1998. http://www.theses.fr/1998CAEN2066.
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Nous avons etudie la production des photons et des pions neutres dans la matiere nucleaire froide, et en particulier la production sous le seuil. Les particules produites sous le seuil dans les collisions d'ions lourds sont en effet des sources uniques d'information sur les caracteristiques de la matiere nucleaire chaude et dense qui est formee lors de ces collisions. Neanmoins, pour pouvoir pleinement utiliser ces sondes, leurs modes de creation et de propagation dans la matiere nucleaire doivent etre connus. Pour parvenir a cette fin les reactions proton-noyau ont ete etudiees a 190 mev. Ce choix elimine de nombreuses caracteristiques inconnues des collisions noyau-noyau qui conduisent a la production dans la matiere nucleaire chaude. Cette experience a ete realisee par la collaboration taps aupres de l'accelerateur franco-hollandais agor au kvi. La mesure concomitante des photons et des pions neutres a rendu possible la determination des sections efficaces de production des photons directs, en permettant d'estimer la contribution des photons issus de la decroissance des pions neutres au spectre total des photons mesures. Le grand nombre de particules detectees nous a permis d'etudier l'evolution des sections efficaces doublement differentielles en fonction de la masse du noyau cible. Cette evolution est notablement differente pour les particules (photons ou pions neutres) les plus energetiques. Il est clair que cette difference indique que le mecanisme de production des particules tres energetiques, au-dela de l'image d'une superposition incoherente de collisions nucleon-nucleon de premiere chance, implique des processus collectifs. Il apparait que le processus de diffusions multiples joue un role important pour la production des photons, production incoherente a basse energie, et coherente (cooperative) a plus haute energie de photon. La confrontation de ces resultats avec les predictions du modele de transport dcm montre les limites de la theorie. En particulier, la precision de la mesure effectuee de la production de particules pres de la limite cinematique (capture pionique du proton) depasse de loin les capacites actuelles du calcul theorique.
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Sazak, Halime. "Measuring the CP Violation Phase γ in open charm B decays at LHCb." Electronic Thesis or Diss., Université Clermont Auvergne (2021-...), 2022. http://www.theses.fr/2022UCFAC115.
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Cette thèse présente l’étude de la mesure de l’angle CKM γ à travers deux analyses possibles à LHCb : première analyse, à partir de la mesure B_s^0→D ~^(┤)0 ϕ désintégration, où la notation D ~^0 désigne soit un D^0 ou un ¯D^0 méson reconstruit en mode de désintégration : Kππ^0, tandis que les ϕ désintégrations vers K^(+K^- ) ; la deuxième analyse, à partir du mode de désintégration plus conventionnel B^(-→D^0 K^- ), où D^0 se désintègre en K^(-π^+ ) (RS), K^(-K^+ ) , π^(-π^+ ) , π^(-K^+ ) (WS) et K^-est reconstruit en K^(-π^0 ). Les deux mesures pour les modes de désintégration utilisant la collision proton-proton sont basées sur une luminosité intégrée de 9.0 〖fb〗^(-1) collectée par le détecteur LHCb pendant les périodes d'exploitation Run 1 & Run 2, accumulées au cours des années 2011 à 2018This thesis presents the study of the measurement of the CKM angle γ through two possible analysis at LHCb: first analysis, from the measurement of B_s^0→D ~^(┤)0 ϕ decay, where the notation D ~^0 stands for either a D^0 or a ¯D^0 meson reconstructed in sub-decay mode: Kππ^0, while the ϕ decays to K^(+K^- ); the second analysis, from the more conventional decay mode B^(-→D^0 K^- ), where D^0 decays to K^(-π^+ ) (RS), K^(-K^+ ), π^(-π^+ ), π^(-K^+ ) (WS) and K^- is reconstructed in K^(-π^0 ). Both measurements for the decay modes using proton-proton collision based on an integrated luminosity of 9.0〖fb〗^(-1) collected by the LHCb detector during Run 1 & Run 2, accumulated over years 2011 to 2018
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Fauth, Anderson Campos 1957. "Observações sobre os momentos transversais dos pions neutros e dos raios gamas do estado intermediário de massa ~3 GeV/c2 (mirim) na produção múltipla de mésons." [s.n.], 1986. http://repositorio.unicamp.br/jspui/handle/REPOSIP/278131.
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Orientador: Kotaro SawayanagiDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
Made available in DSpace on 2018-07-14T09:50:43Z (GMT). No. of bitstreams: 1 Fauth_AndersonCampos_M.pdf: 1371288 bytes, checksum: 06e1353fb3e94790d264614367376eda (MD5) Previous issue date: 1986
Resumo:É obtida a distribuição de momento transversal dos pions neutros de 32 C-jatos Mirins com SEg > 20 TeV através de dois métodos de acoplamento 2g ® pº. Estes resultados independem de qualquer modelo de produção de partículas. Realiza-se uma simulação, pelo método de Monte Carlo, da produção de pions e avalia-se que os dois métodos conseguem obter em média aproximadamente 50% de acoplamentos corretos. Constata-se que a forma da distribuição dos pions neutros depende fracamente da porcentagem de acoplamentos corretos. A distribuição de momento transversal dos pions neutros dos eventos Mirins é obtida por uma terceira maneira, a qual é completamente independente das duas primeiras, que consiste da composição entre uma solução analítica e o método de Monte Carlo. Os resultados dos três métodos são consistentes entre si
Abstract: Not informed.
Mestrado
Física
Mestre em Física
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Fog, Lotte S. "Coherent production of neutral pions on '1'2C and '4'0Ca." Thesis, University of Glasgow, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368746.
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Ko, Ho San. "Neutral Pion Electroproduction and development of a Neutral Particle Spectrometer." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASS129.
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Les distributions de partons généralisées (GPD) sont des objets décrivant la structure interne du nucléon. Les GPD corrèlent les distributions spatial et d'impulsion des partons à l'intérieur du nucléon. Par conséquent, elles contiennent des informations beaucoup plus riches sur la structure du nucléon que les facteurs de forme ou les distributions de partons ordinaires. Les GPD sont accessibles à travers des réactions exclusives où toutes les particules de l'état final sont identiées. La diffusion Compton profondément virtuelle (DVCS) et l'électroproduction exclusive de pions neutres (DVMP) sont discutées dans ce document. Le texte est divisé en quatre chapitres: une introduction, une présentation de l'analyse des données, une description des développements instrumentaux et une courte discussion d'un nouveau matériau scintillant. Une mesure précise du DVCS et du DVMP a été réalisée dans la région de valence à Jefferson Lab, avec un faisceau d'électrons de 11 GeV et une cible de protons. L'analyse des données et les résultats préliminaires de cette expérience sont présentés dans le deuxième chapitre. Une future expérience donnera encore plus de contraintes pour l'extraction des GPD. Pour cette nouvelle expérience un spectromètre à particules neutres (NPS) est en cours de construction. Dans le troisième chapitre des simulations et des développements instrumentaux pour le calorimètre de NPS sont discutés. Enfin, la caractérisation d'un nouveau verre scintillant est montrée brièvement. Ce matériau, encore en phase de développement, est un des candidats pour les calorimètres d'un futur collisionneur électron-ion (EIC)Generalized Parton Distributions (GPDs) are generalized objects describing nucleon structure. GPDs correlate the spatial and the momentum distributions of partons inside the nucleon. Therefore, they provide richer information about the nucleon structure than the well-known form factors and parton distribution functions. GPDs are accessible via exclusive reactions, where all particles in the final state are identifed. Deeply virtual Compton scattering (DVCS) and deeply virtual neutral pion production (DVMP) are discussed. The document is divided into four chapters: physics introduction, data analysis, development of a detector, and a short preview of a new scintillator material. With an 11 GeV electron beam and a proton target at Je_erson Lab, a precise DVCS and DVMP experiment in the valence quark region was performed. The data analysis and preliminary results of this experiment are presented in the second chapter. An upcoming experiment will give more constraints on the extraction of GPDs. For this new experiment, a neutral particle spectrometer (NPS) is under construction. In the third chapter, simulation studies and hardware developments for the NPS calorimeter are presented. Finally, characterizations of a new glass scintillator are shortly discussed. This material, which is in an early stage of development, is one of the candidates for the calorimeters of a future Electron-Ion Collider (EIC)
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Meekins, David G. "Coherent neutral pion photoproduction on the deuteron." W&M ScholarWorks, 1998. https://scholarworks.wm.edu/etd/1539623932.
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The differential scattering cross section for the process gd→dp0 was measured, as part of experiment E89-012 at Thomas Jefferson National Accelerator Facility. The experiment was performed in Hall C during the Spring of 1996 as the commissioning experiment for the Hall C cryogenic target. The High Momentum Spectrometer was used to detect the recoil deuteron and no effort was made to detect the p0 or its decay photons. The differential cross section was measured at a number of incident photon energies between 0.8 GeV and 4.0 GeV for the deuteron center-of-mass angles of 90?? and 136??. The data were found to disagree with both the constituent counting rule and reduced nuclear amplitude predictions. These are the first data at large deuteron center-of-mass angles for photon energies larger than 1.6 GeV.
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Carroll, Michael. "Measurement of CP violation parameters in neutral kaon decay of two charged pions." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363990.
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Kochanek, Izabela. "Analysis of neutral pions from vµ CC CNGS interactions in the ICARUS detector." Doctoral thesis, Katowice : Uniwersytet Śląski, 2015. http://hdl.handle.net/20.500.12128/5906.
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The aim of the thesis is the study of the electromagnetic showers and neutral mesons in the ICARUS T600 Liquid Argon Time Projection Chamber. To accurately reconstruct energy of electromagnetic showers, different corrections to the collected charge are needed. In this thesis the author calibrated the energy reconstruction with a set of corrections, most of which are not present in the official ICARUS reconstruction software. For this goal, the simulation package FLUKA was extensively used in order to study the ionization quenching and
the shower containment in the detector. As a result the reconstructed invariant ⇡0 masses are distributed compactly (" = 12 MeV/c2) with
a best value equal to 134.5 ± 1.5 ± 4.2 MeV/c2. Moreover, other results on low energy electromagnetic showers in Liquid Argon were found which include the longitudinal profile parametrization, the conversion
distance measurement and the ionization losses for 1 and 2 m.i.p. particles. This latest point is interesting for the e CC events selection from ⌫μ NC background.
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Gardner, Simon. "Polarisation observables in neutral pion photoproduction with MAMI." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/8024/.
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This thesis presents new high statistics measurements of polarisation observables in neutral pion photoproduction from experiments carried out with the Crystal Ball at the Mainzer Microtron (MAMI) in Mainz. The polarisation observable Σ has been measured in the γp → π0 p reaction in the region between the ∆(1232) and second resonance region. Measurements of observables Σ, I s and I c in the γp → 2π0 p reaction have been made from the 2π 0 threshold, a lower energy than previously measured. All measurements produced for this thesis have been sent to partial wave analysis groups where they will be used to provide constraints to their models. In particular, the 2π 0 measurements are expected to have an impact on our understanding of the poorly constrained properties of the N(1440) resonance, such as the branching ratios of its decay through intermediate meson or ∆ pathways. The sPlot technique has been used for the first time in photoproduction experiments with advantages over other techniques discussed. The development of the technique for such analysis as this will be key for the extraction of many observables from future measurements.
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Kimmel, Jr Taylor Douglas. "Analysis of Neutral D Meson Two-Body Decays to a Neutral Kaon and a Neutral Pion." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/105001.
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Decays of neutral D mesons to final states containing K + π's could provide evidence for
CP-violation from a source not accounted for in the Standard Model. Due to the interference
between Cabibbo-favored and Cabibbo-suppressed transitions, a decay rate asymmetry of
D0 → K0S π0 compared to D0 → K0Lπ0 has been predicted to be non-zero. If New Physics
interferes in doubly Cabibbo-suppressed D decays, the measurement of this asymmetry would
differ from the predicted value and may provide evidence for CP-violation beyond the CKM
mechanism. I present an analysis method to measure this branching fraction asymmetry,
R(D0) ≡ B(D0→K0S π0)−B(D0→K0L π0)/(B(D0→K0Sπ0)+B(D0→K0Lπ0)), utilizing e+e− → cc events in the Belle dataset.Doctor of Philosophy
The Universe appears to be made almost entirely of matter rather than antimatter; however, matter and antimatter should have been created in equal amounts in the Big Bang. We do not know exactly why we observe so much more matter as compared to antimatter. The Standard Model (SM) of particle physics accounts for some of the asymmetry through Charge-Parity (CP) symmetry violation, which explains how particles behave differently than their corresponding antiparticles. In the current state of the SM, some CP-violation is allowed in decays via the weak force, but the theory does not account for enough CP violation to explain the amount of matter-antimatter asymmetry observed in the Universe. Decays of a D meson to a kaon (K meson) plus one or more pions (π mesons) via a new mechanism beyond the weak force could provide evidence of a new source of CP-violation. In this analysis, I present a method for analyzing the decays of neutral D mesons to a neutral kaon and a neutral pion in the Belle dataset to test the SM.
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Sokhan, Daria. "Beam asymmetry measurement from pion photoproduction on the neutron." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4336.
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The resonance spectrum of the nucleon gives direct information on the dynamics and interactions of its constituents. This offers an important challenge to the theoretical models of nucleon structure, including the emerging Lattice QCD predictions, conformal field theories and more phenomenological, QCD-based approaches. Although the various models predict different features for the excitation spectra, the experimental information is currently of too poor quality to differentiate between these models. Pion photoproduction from the nucleon is a powerful probe of the spectrum as most resonances are expected to couple to the pion decay channel. However, cross-sections alone are not sensitive enough to allow identification of the underlying excitation spectrum, as the resonances have energy widths larger than their separations. A major world effort is underway to additionally measure polarisation observables in the production process. For a model-independent analysis a “complete” set of single- and doublepolarisation observables needs to be measured in experiments involving polarised beams, targets and a means of determining recoil nucleon polarisation. In particular, the beam asymmetry is a critical observable for the constraint of partial wave analyses (PWA) used to extract the nucleon excitation spectrum from the data. Almost all of the available world data on the beam asymmetry has been taken on the proton, with the neutron dataset sparse, containing only three experiments at fixed angles and in a limited photon energy range. The lack of extensive data on the neutron is a major deficiency, as different resonances have very different electromagnetic couplings to the proton and neutron. As a result, the data from the two targets will have very different relative contributions from, and sensitivities to, the spectrum of nucleon resonances. Moreover, neutron data is essential for the separation of the isoscalar and isovector components of the reaction amplitudes. This thesis presents a very high statistics measurement of the photon beam asymmetry on the neutron with close-to-complete angular coverage and a wide range of invariant mass (1610 – 2320 MeV) extending over the third resonance region, where the excitation spectrum is particularly ill defined. The experiment was conducted at the Thomas Jefferson National Accelerator Facility (JLab) using a tagged, linearly polarised photon beam, a liquid deuterium target and the CEBAF Large Acceptance Spectrometer (CLAS). The quality and quantity of the data has allowed an invariantmass resolution of 10 MeV and an angular resolution of 0.1 in the cosine of the centre-of-mass pion production angle, θ. Good agreement is evident in the regions where there is kinematic overlap with sparse previous data. Comparison of the new data is made with the two main partial wave analyses, SAID andMAID. Significant discrepancy is observed at backward θ with SAID (across most of the energy range) and MAID (up to ∼ 1750 MeV) and also below ∼ 35◦ in θ with both analyses. This extensive new dataset will help significantly to constrain partial wave analyses and will be a crucial part of the current world effort to use meson photoproduction to tackle long-standing uncertainties in the fundamental excitation spectrum of the nucleon. As a first step towards this the refitting of the SAID partial wave analysis incorporating the new data was carried out and shows very significant changes in the properties of the magnetic P11, P13, D13, D35, F15, G17 and G19 partial waves.
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Fonvieille, Hélène. "Électroproduction inverse au seuil et désintégration de Dalitz du pion neutre." Clermont-Ferrand 2, 1989. http://www.theses.fr/1989CLF2E420.
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Les réactions d'électroproduction inverse de pion au seuil (1) et désintegrati0n de Dalitz du pion neutre (2) sont étudiées par capture de pions à l'arrêt. L'expérience utilise le faisceau de pions de l'accélérateur linéaire de Saclay, une cible d'hydrogène liquide, et un double spectromètre magnétique détectant la paire de leptons. Par une analyse différentielle, on extrait la partie dynamique des processus, testant ainsi les modèles d'interaction forte à basse énergie. Pour la réaction (1), une séparation transverse-longitudinale en fonction de la masse carrée du photon virtuel et de son taux de polarisation a permis de mesurer les multipôles d'onde s: en valeur relative (multipôle électrique transverse) et absolue (multipôle longitudinal). L'étude de la réaction (2) a permis de mesurer le facteur de forme électromagnétique de transition du pion neutre, et son paramètre de pente
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Short, Samantha. "Study of neutrino-induced neutral current neutral pion production in the T2K near detector." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11688.
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The T2K experiment is a long baseline neutrino oscillation experiment. The most intense accelerator muon neutrino beam ever built is produced at the J-PARC facility in Tokai, located on the east coast of Japan, and directed (2.5 [degrees] off -axis) toward the Super-Kamiokande water Cherenkov detector, located 295 km away in the mountains of western Japan. For the current T2K [Symbol appears here. To view, please open pdf attachment]e appearance analysis, 23% of the background at Super- Kamiokande is from neutral current interactions that produce one π0 in the final state (NC 1π0). This study uses ND280 Run 2 data totalling 7.832 x 10 [to the power of 19] POT and selects neutrino-induced NC 1π0 interactions in FGD1 and FGD2 where both π0 decay photons convert in the barrel and downstream ECAL. Overall, neglecting photon reconstruction efficiency, an efficiency of 22% and purity of 16% is obtained. For the case where both π0 decay photons convert in the downstream (barrel) ECAL an efficiency of 33% (12%) and purity of 43% (9%) is achieved. When one photon converts in the barrel ECAL and the other in the downstream ECAL the efficiency (purity) is 29% (16%). Systematic uncertainties arising from cross-section model parameters and final state interactions, the neutrino flux prediction and the shape discrepancy between ECAL variables in data and MC are evaluated. The predicted total number of events when both photons convert in the downstream and barrel ECAL is 7.1± 2.3 (syst)± 0.5 (stat) and 31.6± 8.9 (syst) ±1.2 (stat), respectively. Whereas when one decay photon is reconstructed in the barrel ECAL and the other in the downstream ECAL the expected number of events is 38.1± 8.7 (syst) ±1.3 (stat). The selected number of events in data is 5, 22 and 31, respectively, which agrees with the prediction within errors. The calibration of the time offsets for the barrel and downstream ECAL is also presented in this thesis. The application of this calibration reduces the timing resolution from 9 ns to approximately 2.5 ns, for high charge hits.
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kurimoto, Yoshinori. "Measurement of Neutral Current Neutral Pion Production on Carbon in a Few-GeV Neutrino Beam." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120650.
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Titov, A. I., T. I. Gulamov, and Burkhard Kämpfer. "Neutral roh-meson properties in an isospin-asymmetric pion medium." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32202.
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Ghaderi, Hazhar. "The Rare Decay of the Neutral Pion into a Dielectron." Thesis, Uppsala universitet, Kärnfysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-211683.
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We give a rather self-contained introduction to the rare pion to dielectron decay which in nontrivial leading order is given by a QED triangle loop. We work within the dispersive framework where the imaginary part of the amplitude is obtained via the Cutkosky rules. We derive these rules in detail. Using the twofold Mellin-Barnes representation for the pion transition form factor, we derive a simple expression for the branching ratio B(π0
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Titov, A. I., T. I. Gulamov, and Burkhard Kämpfer. "Neutral roh-meson properties in an isospin-asymmetric pion medium." Forschungszentrum Rossendorf, 1994. https://hzdr.qucosa.de/id/qucosa%3A22047.
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Guzowski, Pawel. "Reconstruction of neutrino induced neutral current neutral pion events with the T2K ND280 Tracker and ECAL." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11067.
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T2K is a long baseline neutrino oscillation experiment in Japan. One of the goals is to search for electron neutrino appearance at the far detector (Super Kamiokande) in a muon neutrino beam produced 295 km away, to make a measurement of the unknown neutrino oscillation angle [Symbol appears here. To view, please open pdf attachment]13. A major background to this appearance search is neutral pions (π0) produced in neutral current (NC) neutrino interactions. The π0s decay to photons, which can in cases mimic the electron appearance signal. The near detector of the experiment (ND280) has the capability of measuring the rates of NCπ0 production processes. NCπ0 interactions in the Tracker of the detector (plastic scintillator targets, and time projection chambers for tracking charged particles) can be detected through photon conversions in the electromagnetic calorimeter that surrounds the Tracker. For these types of events, the photon reconstruction in the calorimeter has to have good energy and angular resolutions. This thesis describes the T2K experiment, the ND280 detector and its offline software, and gives details on the ECal reconstruction of photons. The performance of the reconstruction in relation to the π0 decay photons, their energy and angular resolutions, is studied. An analysis is presented for the reconstruction of NC π0s produced in the trackers, with both photons converting in the downstream calorimeter, developed purely with Monte Carlo (with GENIE as the interaction generator), and then applied to the first-year data from ND280. The Monte Carlo expectation is 17.7 ± 1.1(stat) ± 4.9(syst) events, with 37 ± 4% NCπ0 purity; 21 events are seen in the first year data. The MC is consistent with data at the 0.5σ level. As a crosscheck, the same analysis is applied to a different Monte Carlo production (using NEUT as the generator). The expectation from this production is 16.8 ± 1.0(stat) ± 4.7(syst) events, with 30 ± 4% purity. This is consistent with data at the 0.7σ level.
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Bensayah, Mohammed Nadji. "Etude de la désintégration ... mesure du facteur de forme électromagnétique du pion neutre /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37611773z.
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Paquet, Jean-François. "Photon and neutral pion production in d-Au collisions at RHIC." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97207.
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The cross-section of large transverse momentum photons and neutral pions in proton-proton collisions is calculated using the standard perturbative QCD formula at leading twist, next-to-leading order, and is compared to data from the Relativistic Heavy Ion Collider (RHIC). The cross-section of hard photons and neutral pions is also calculated for deuteron-gold collisions using a model based on an extension of the proton-proton calculation to nucleus-nucleus collisions and on phenomenological nuclear parton distribution functions. The deuteron-gold calculations are compared to data measured at the same collider. The effect of parton energy loss on the deuteron-gold calculations is also investigated.La section efficace des photons et des pions neutres ayant de grandes quantités de mouvement tranversales produits dans des collisions proton-proton est calculée en utilisant la formule standard basée sur la chromodynamique quantique (QCD) perturbative. Les calculs sont faits au premier "twist" et au second ordre, et sont comparés à des mesures provenant du "Relativistic Heavy Ion Collider" (RHIC). La section efficace est aussi calculée pour des collisions deutéron-or à l'aide d'un modèle basé sur des distributions de partons nucléaires et sur un prolongement de la formule des collisions proton-proton aux collisions noyau-noyau. Les calculs basés sur ce modèle sont comparés à des mesures provenant du même accélérateur. L'effet des pertes d'énergie des partons sur les calculs de sections efficaces dans les collisions deutéron-or est aussi étudié.
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Ryan, Garrett. "Maximum Mass Restraint of Neutron Stars: Quarks, Pion, Kaons, and Hyperons." Scholarship @ Claremont, 2017. http://scholarship.claremont.edu/cmc_theses/1535.
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This thesis explores the topic of maximum mass stability of neutron stars. The outer structure is detailed and explores nuclear pasta phases, the neutron drip line, and density transitions of matter in the crust and atmosphere layers. Other discussion points include superfluids in the crust and core, vortex roles in neutron stars, and magnetic field effects on the EOS in neutron stars. The inner core is studied in much more detail due to its significant role in EOS. The variety of stars include pion condensate stars, kaon condensate stars, npeu stars, npeu stars with the inclusion of hyperons, quark-hybrid stars, and strange stars. Included with these is a description of nucleon-nucleon, nucleon-nucleon-nucleon interactions, the appearance factors that affect hyperon species, and the formation process of kaons, pions, quarks, and hyperons. The ending EOS are compared with their maximum mass values to determine which ones are likely to limit the mass of neutron stars.
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Conti, Camila de. "Proposta de um novo calorímetro eletromagnético para o experimento ALICE - LHC." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-22012015-135852/.
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No presente trabalho é explorada a performance do FoCal, um calorímetro eletromagnético frontal, com alta resolução espacial, proposto como um upgrade para o experimento ALICE, no LHC. O principal objetivo deste detector é fazer a medida de fótons diretos na região de pseudo-rapidez 2.5 < < 4.5. Essa região frontal é dominada por fótons provenientes do decaimento de hadrons, principalmente do píon neutro , e portanto uma eficiente medida de fótons diretos está diretamente associada à eficiência em se identificar fótons provenientes do decaimento do píon neutro. Para distinguir fótons diretos de fótons de decaimento do píon neutro, são explorados três diferentes métodos de análise, a saber, massa invariante, análise da forma do chuveiro e isolamento, sendo cada um deles adequado a uma diferente faixa de energia do píon neutro. O método da massa invariante permitiu identificar fótons de píon neutro com uma eficiência de 95% num ambiente de partículas únicas, para píon neutro com energia entre 0 e 300 GeV. Num ambiente pp, esse método mostra uma eficiência de 85%. A análise da forma do chuveiro foi capaz de identificar, com um dado corte no parâmetro de forma Width1, fótons diretos com uma eficiência acima de 90% e de rejeitar fótons de píon neutro com uma eficiência que varia de 65% a 95%, no intervalo de energia de 300 GeV a 500 GeV, num ambiente de partículas únicas. Essas eficiências podem ser melhoradas se for aplicado um corte dependente da energia e a rejeição de píon neutro pode também ser melhorada se os eventos mais assimétricos puderem ser melhor reconstruídos pelo detector no futuro. No método de isolamento, aplicado ao ambiente pp e PbPb, é explorado o melhor valor de raio de isolamento Riso a ser usado em cada ambiente. Por este método podem ser atingidas altas eficiências em detectar fótons diretos, mas o método se mostra limitado pelo grande fundo de fótons de decaimento, e a pureza dos cortes testados não atinge valores maiores que cerca de 10%. E mostrado que o uso de um trigger em 40 GeV pode melhorar a pureza dos cortes de 0.01 % para cerca de 10%. Foi feita a otimização de alguns parâmetros de análise, permitindo melhor desempenho desses métodos de análise exploradosIn the present work is explored the performance of the FoCal, a forward electromagnetic calorimeter, with high granularity, proposed as an upgrade for the ALICE experiment, in LHC. The main goal of the detector is to be able to identify direct photons in the pseudo-rapidity region 2.5 < < 4.5. This forward region is dominated by decay photons, mainly photons from neutron pion decay, so an efficient mesurement of direct photons is directly associated to the efficiency in identify photons from neutron pion decay. To separate direct photons from neutron piondecay photons, it is explored three different analysis methods, the invariant mass, shower shape and isolation, each one useful in a different energy range of the neutron pion. The invariant mass method allowed to identify photons from neutron pion with an efficiency around 95% in a single particle environment, for neutron pion with energy between 0 and 300 GeV. In a pp environment, this method showed an efficiency of 85%. The shower shape method was able to identify, by a given cut in the shower shape parameter Width1, direct photons with an efficiency of 90% and to reject 65% to 95% of the photons from neutron pion in the energy range of 300 GeV to 500 GeV, in a single particle environment. This efficiencies can be improved if there is aplied a cut that depends on the energy and the neutron pion rejectioncan also be improved if the more assimetric decays can be better reconstructed by the detector in the future. The isolation method is aplied to a pp and PbPb environments, and it is explored the best value of isolation radius Riso to be used in each environment. By this method, it can be reached high efficiencies in detecting direct photons, but the method is limited by the high background of decay photons, and the purity of the cuts is not better than about 10%. It is showed that a trigger in 40 GeV can improve the purity from 0.01% to about 10%. It was made an optimization of some of the used analysis parameters, leading to an improvement of the explored analysis methods.
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Wilson, Michael Galante. "Analysis of [neutral-D to a charged kaon, a charged pion, and a neutral pion] decays : Search for [neutral-D] mixing, and measurements of the doubly Cabibbo-suppressed decay rate and resonance contributions /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2005. http://uclibs.org/PID/11984.
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Reposeur, Thierry. "Etude de l'interaction proton- proton dans la voie inelastique de production d'un pion neutre." Paris 7, 1989. http://www.theses.fr/1989PA077167.
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Ullrich, Matthias Gunter [Verfasser]. "Measurement of sigma (psi(3770) to proton antiproton neutral pion) and determination of sigma (proton antiproton to psi(3770)neutral pion) for the PANDA experiment / Matthias Gunter Ullrich." Gießen : Universitätsbibliothek, 2014. http://d-nb.info/1068275812/34.
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Lenkewitz, Mark [Verfasser]. "Neutral Pion Electroproduction off Light Nuclei in Chiral Perturbation Theory / Mark Lenkewitz." Bonn : Universitäts- und Landesbibliothek Bonn, 2013. http://d-nb.info/1045872075/34.
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Rahmat, Rahmat. "Hadronic spectrum of [tau lepton to antipion-neutral pion-tau neutrino] decays /." Connect to title online (ProQuest), 2008. http://proquest.umi.com/pqdweb?did=1617382331&sid=4&Fmt=2&clientId=11238&RQT=309&VName=PQD.
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Thesis (Ph. D.)--University of Oregon, 2008.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 144-149). Also available online in ProQuest, free to University of Oregon users.
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Lawe, Matthew. "Study of charged current neutral pion production in the T2K Near Detector." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/8562/.
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T2K is a long-baseline neutrino oscillation experiment based at the J-PARC research facility in eastern Japan. The main systematic uncertainties dominating the neutrino oscillation analyses for T2K are related to the beam flux, cross-section and final state interaction uncertainties. Within this thesis, a first attempt is made to develop an analysis to reconstruct charged-current single neutral-pion interactions within the tracking detector region of the T2K near detector. The analysis presented is divided into six topologies and produces a selection efficiency, over all the event topologies of interest, of 9.6% with 12.1% purity. When considering the most effective selection topology, labelled FGD2DsDs, an efficiency of 9.4% with purity of 22.6% is achieved. This leads to a FGD2DsDs Monte-Carlo prediction of 58.5 ± 3.5 (stat.) ± 15.4 (syst.) events being selected across the T2K Run 2, Run 3 and Run 4 data taking periods, with a total of 58 events being selected within the real data. With further development in the future, it is expected that the presented analysis will contribute towards the data samples used to constrain the T2K experiment oscillation analysis and lead to a CC1pi0 final state cross-section measurement.
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Torii, Hisayuki. "Midrapidity neutral-pion production in proton-proton collisions at [root]s=200GeV." 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/145481.
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Kyoto University (京都大学)0048
新制・課程博士
博士(理学)
甲第11177号
理博第2845号
新制||理||1425(附属図書館)
22761
UT51-2004-T146
京都大学大学院理学研究科物理学・宇宙物理学専攻
(主査)教授 今井 憲一, 教授 植松 恒夫, 教授 西川 公一郎
学位規則第4条第1項該当
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Rahmat, Rahmat 1974. "Hadronic spectrum of tau lepton to antipion-neutral pion-tau neutrino decays." Thesis, University of Oregon, 2008. http://hdl.handle.net/1794/8569.
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xix, 149 p. ; ill. (some col.) A print copy of this title is available through the UO Libraries. Search the library catalog for the location and call number.We report on a study of the invariant mass spectrum of the hadronic system in à - [arrow right] à - à 0 à à à à à ½ à decays. This study was performed using data obtained with the BABAR detector operating at the PEP-II e + e - collider. We present fits to phenomenological models in which resonance parameters associated with the à (770), à '(1450) and à "(1700) mesons are determined. We also discuss the implications of our data with regard to estimates of the hadronic contribution to the muon anomalous magnetic moment.
Adviser: Eric Torrence
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Nix, Oliver. "Suche nach odderoninduzierten Beiträgen in exklusiver pi 0-Produktion mit dem Detektor H1 bei HERA." [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB9394026.
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Maly, Enrico. "Untersuchung neutraler pi-Mesonen mit dem elektromagnetischen Kalorimeter des BABAR-Detektors." [S.l. : s.n.], 2004. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10976060.
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Odier, Philippe. "Mesure de la production inclusive de pio dans les desintegrations hadroniques du z#o avec le detecteur aleph au lep." Chambéry, 1995. http://www.theses.fr/1995CHAMS018.
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Ce memoire presente une mesure de la production inclusive de pio dans les desintegrations hadroniques du z#o avec l'experience aleph au lep. Cette mesure s'inscrit dans le cadre de l'etude de la production des hadrons issus de la fragmentation des quarks et des gluons, decrite pour la partie perturbative par la chromodynamique quantique et pour la partie non perturbative par des modeles phenomenologiques. Nous commencons par une breve revue de l'etat actuel des connaissances sur ces deux aspects de la fragmentation. L'analyse presentee ensuite utilise deux millions d'evenements, selectionnes parmi les donnees prises par aleph pendant les annees 1992, 93 et 94. Les pio sont reconstruits a partir de leur desintegration en deux photons. Ces photons sont identifies soit par leur depot d'energie dans le calorimetre electromagnetique, soit a partir de leur conversion en une paire electron-positron, detectee dans les chambres a traces. Au cours des differentes etapes de la selection des photons, les efficacites calculees avec le monte-carlo sont controlees a l'aide des donnees elles-memes. Le signal des pio est alors extrait par un ajustement des distributions de masse invariante photon/photon. Les trois combinaisons de photons (converti/calorimetrique, calorimetrique/calorimetrique et converti/converti) sont utilisees. Les sections efficaces differentielles en energie, impulsion transverse et rapidite sont mesurees. Le nombre de pio mesures par evenement pour e#p#i#o superieure a 1. 14 gev est: n(pio) = 5. 24 0. 02 (stat. ) 0. 29 (syst. ) ces resultats sont compares a ceux obtenus par d'autres experiences lep, aux resultats obtenus par aleph sur les pions charges, ainsi qu'aux predictions de differents generateurs d'evenements. Un accord raisonnable est observe, meme si nous mesurons une section efficace legerement superieure, l'ecart atteignant deux deviations standard a basse energie. Pour terminer, une breve etude topologique est presentee, utilisant les variables globales d'evenement
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He, Yanyi. "2+1 correlation between neutral pions and charged hadrons in gold-gold collisions at center of mass energy = 200GeV." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1465704.
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Moisan, Christian. "Neutral pion production in the reactions 160+27Al, 58Ni, 208Pb at 95 MeVu." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59518.
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The inclusive production of neutral pions has been measured in reactions of 95 MeV/nucleon $ sp{16}$O+$ sp{27}$Al, $ sp{58}$Ni, $ sp{208}$Pb, using a setup of 8 lead-glass Cherenkov counter telescopes to detect in coincidence the two photons resulting from pion decays. The differential distributions of interest: d$ sigma$/dT$ sb{ pi}$, d$ sigma$/d$ Omega$, d$ sigma$/dy and d$ sigma$/dp$ sb{ rm t}$ are obtained from the experimental invariant cross section of the pions. The transverse momentum, kinetic energy, and angular distributions, are discussed in the framework of the moving thermal source model. The shape of d$ sigma$/dp$ sb{ rm t}$ and d$ sigma$/dT$ sb{ pi}$ is reproduced by a single source having a temperature close to 20 MeV and moving with a velocity between that of the nucleus-nucleus and the nucleon-nucleon center of mass rest frames. Relevant signatures of the energy and angular dependences of pion reabsorption have been extracted from the data. The deviations of the energy distributions from the thermal model predictions are consistent with the deduced behavior of reabsorption. It is also shown that the absorption can explain the evolution of the anisotropy of the angular distributions with the target mass.
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Sanderson, Ruth. "Coherent neutral pion photoproduction on ¹â¶O and ²â°â¸Pb." Thesis, University of Glasgow, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248275.
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Lurkin, Nicolas. "Neutral pion transition form factor measurement and run control at the NA62 experiment." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7617/.
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The measurement of the π0 electromagnetic transition form factor (TFF) slope a is performed in the time-like region of momentum transfer using a sample of 1.1 x 106 π0→ e+e-y Dalitz decay collected at the NA62-RK experiment in 2007. The event selection, the fit procedure and the study of the systematic effects are presented. The final result obtained a = (3.68 ± 0.51stat ± 0.25syst) X 10- 2 is the most precise to date and represents the first evidence of a non-zero π0 TFF slope with more than 3σ. The NA62 experiment based at the CERN SPS is currently taking data and aims at measuring the branching fraction of the K→ πvv ultra-rare decay with 10% precision and less than 10% background. A complex trigger and data acquisition system is in place to record the data collected by the various detectors in use to reach this goal. The Run Control system of the experiment is meant to supervise and control them in a simple transparent way. The choices made to address the requirements for the system and the most important aspects of its implementation are discussed.
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Arms, Kregg E. "Study of tau lepton decays to three charged hadrons and one neutral pion." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1112803154.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains xv, 81 p.; also includes graphics (some col.) Includes bibliographical references (p. 79-81). Available online via OhioLINK's ETD Center
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Niclasen, Rune. "Measuring the branching ratio of the rare decay neutral pion going to electron-positron." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3207725.
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Foucault, Pascal. "Photoproduction des mesons d : desintegration du d neutre dans un canal avec un pion neutre, caracteristiques de l'hadronisation du charme et de la dynamique de production." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13216.
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Foucault, Pascal. "Photoproduction des mésons D désintégration du D neutre dans un canal avec un pion neutre, caractéristiques de l'hadronisation du charme et de la dynamique de production /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37613681s.
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Aoki, Kazuya. "Double helicity asymmetry of inclusive neutral pion production in polarized pp collisions at √s=62.4GeV." 京都大学 (Kyoto University), 2009. http://hdl.handle.net/2433/126579.
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Kyoto University (京都大学)0048
新制・課程博士
博士(理学)
甲第14992号
理博第3471号
新制||理||1508(附属図書館)
27442
UT51-2009-R716
京都大学大学院理学研究科物理学・宇宙物理学専攻
(主査)教授 今井 憲一, 教授 永江 知文, 准教授 中家 剛
学位規則第4条第1項該当
50
Raaf, Jennifer Lynne. "A Measurement of the Neutrino Neutral Current π0 Cross Section at MiniBooNE." Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1116006438.
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Thesis (Ph. D.)--University of Cincinnati, 2005.Title from electronic thesis title page (viewed Jul. 11, 2006). Includes abstract. Keywords: neutrino; neutral current; cross section; single pion; resonant; coherent; flux-averaged. Includes bibliographical references.