Tesi sul tema "Saveur des quarks"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Vedi i top-29 saggi (tesi di laurea o di dottorato) per l'attività di ricerca sul tema "Saveur des quarks".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Vedi le tesi di molte aree scientifiche e compila una bibliografia corretta.
Espagnon, Bruno. "Etude de la brisure de symetrie de saveur dans la mer de quarks legers du nucleon au moyen du processus drell-yan". Clermont-Ferrand 2, 1995. http://www.theses.fr/1995CLF21694.
Testo completoBonis, Isabelle de. "Etude des désintégrations semi-leptoniques du méson B, dans les canaux D*lv et Dlv, auprès du détecteur ALEPH, au LEP : mesure de la fonction de fragmentation du quark b et recherche d'états D**". Lyon 1, 1994. http://www.theses.fr/1994LYO10156.
Testo completoVale, Silva Luiz Henrique. "Phénoménologie de modèles à symétrie droite-gauche dans le secteur des quarks". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS249/document.
Testo completoThough very successful in explaining a wide variety of particle physics phenomena, the Standard Model (SM) leaves unexplained some properties of nature. Here we focus on the different behaviours of left- and right-handed chiralities, or in other words the violation of parity symmetry. A possible and somewhat natural avenue to explain this feature is to embed the SM into a more symmetric framework, which treats the chiralities on equal footing. This class of models, the Left-Right (LR) Models, introduces new gauge interactions that couple preferentially to right-handed fields. Then, at an energy scale high enough, LR symmetry is spontaneously broken through the Brout-Englert-Higgs (BEH) mechanism, thus giving origin to the SM and to parity violating phenomena. The specific way in which the BEH mechanism operates in LR Models can be probed by EW Precision Observables, consisting of quantities that have been very accurately measured, serving as a first test of consistency for extensions of the SM in the EW sector. We revisit a simple realization of LR Models containing doublet scalars, and consider the phenomenological study of this doublet scenario in order to test the viability and structure of the LR Models. In particular, there is a rich phenomenology associated to the new gauge bosons W’ et Z’ introduced by LR Models, such as new sources of CP violation beyond the one of the SM. Moreover, the extended neutral scalar sector introduces Flavour Changing Neutral Couplings (FCNC) at tree level, which are strongly suppressed in the SM where they arrive first at one loop. FCNCs typically lead to extremely powerful constraints since they contribute to meson-mixing processes, and therefore deserve close attention. For this reason, we consider the calculation of short-distance QCD effects correcting the LR Model contributions to meson-mixing observables up to the Next-to-Leading Order (NLO), a precision required to set solid lower bounds on the LR Model scales. Finally, we combine in a global fit electroweak precision observables, direct searches for the new gauge bosons and meson oscillation observables in the simple case where the right-handed analogous of the CKM mixing-matrix is equal to the CKM matrix itself (a scenario called CKMfitter symmetry). The full set of the observables is combined by using the CKMfitter statistical framework, based on a frequentist analysis and a particular scheme for modeling theoretical uncertainties. We also discuss other possible modelings of theoretical uncertainties in a prospective study for future global flavour fits made by the CKMfitter Collaboration
Guth, Manuel [Verfasser], Gregor [Akademischer Betreuer] Herten, Henri [Akademischer Betreuer] Bachacou e Frédéric [Akademischer Betreuer] Déliot. "Search for tt̄H(bb̄) Production in the Lepton + Jets Channel and Quark Flavour Tagging with Deep Learning at the ATLAS Experiment = Recherche de la production tt̄H(bb̄) dans le canal lepton+jets et étiquetage de quarks de saveur lourde par apprentissage profond dans l'expérience ATLAS". Freiburg : Universität, 2021. http://d-nb.info/1233018728/34.
Testo completoGuth, Manuel [Verfasser], Gregor [Akademischer Betreuer] Herten, Henri [Akademischer Betreuer] Bachacou e Frédéric [Akademischer Betreuer] Déliot. "Search for ttH(bb) Production in the Lepton + Jets Channel and Quark Flavour Tagging with Deep Learning at the ATLAS Experiment = Recherche de la production ttH(bb) dans le canal lepton+jets et étiquetage de quarks de saveur lourde par apprentissage profond dans l'expérience ATLAS". Freiburg : Universität, 2021. http://d-nb.info/1232644676/34.
Testo completoToucas, Guillaume. "Mécanisme de brisure de symétrie chirale pour trois saveurs de quarks légers et extrapolation de résultats de chromodynamique quantique sur réseau". Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00754994.
Testo completoKhreich, Gaëlle. "Angular Analysis of Bs->Phiee Decays and Implementation of Automated Analyses to Ensure Data Quality for Run3 of the LHCb Experiment". Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASP041.
Testo completoOne of the effective ways to search for signs of New Physics (NP) beyond the Standard Model (SM) is through the study of b→sℓ+ℓ− (ℓ is a lepton) transitions, which involve Flavour Changing Neutral Currents (FCNC) via box or loop diagrams. While the SM predicts that the photon is predominantly left-handed in b→sγ transitions, with a small right-handed component, the presence of New Physics (NP) could manifest as a more substantial right-handed current. LHCb has previously conducted an angular analysis on B→K*ee in the low dielectron mass region where the primary contributions to the loop processes arise from the coupling of a virtual photon to the dielectron pair. It has delivered the world's most accurate measurement of photon polarization in b→sγ transitions. The objective of my thesis is to conduct an angular analysis on the Bs→ϕe+e− decay channel in the low dielectron mass region, utilizing the complete LHCb dataset corresponding to an integrated luminosity of 9 fb-1 of proton-proton collisions. This analysis aims to provide a clean and novel measurement of photon polarization, marking the first instance of such an analysis with the Bs meson. Furthermore, it complements the previously established measurements in the B0 channel.The second aspect of my thesis involved the development of an online monitoring tool for use during Run 3 at LHCb. With the LHC transitioning to higher luminosity and generating larger data samples, real-time monitoring of physics variables becomes increasingly crucial. This automatic analysis tool is utilized to detect anomalies by conducting checks on data collected in real-time, ensuring the integrity and reliability of the experimental data
Rosnet, P. "Les saveurs lourdes dans les collisions d'ions lourds ultra-relativistes". Habilitation à diriger des recherches, Université Blaise Pascal - Clermont-Ferrand II, 2008. http://tel.archives-ouvertes.fr/tel-00262436.
Testo completoVincent, Pascal. "Mesure des rapports d'embranchement semi-leptoniques et de la contribution baryonique dans les désintégrations du quark b". Lyon 1, 1994. http://www.theses.fr/1994LYO10090.
Testo completoBorowski, Witold. "Charme ouvert dans les collisions des ions lourds et p+p avec STAR au RHIC". Nantes, 2012. http://www.theses.fr/2013NANT2079.
Testo completoHeavy quarks, namely c and b, at the RHIC energy scale are produced mainly in the early stages of the collision. Thus they are expected to be a good probe to study the _rst moments of the system formation. However the analysis of the spectra of non-photonic electrons, that comes form c and b semi-leptonic decays, shows suppression of the nuclear modi_cation factor for the large transverse momenta (pT) similar to the one measured for the light _avor hadrons, which contradicts the theoretical prediction. To understand this phenomenon a separate measurement of the c and b contribution to those spectra had to be carried out. This has already been done for the proton-proton collisions at 200 GeV. For this study in the STAR experiment a special technique, the electron_D0 azimuthal angular correlations has been developed. This thesis shows that the capabilities of the current setup of the STAR detector do not allow to perform this kind of measurement in the Gold Gold collisions at 200 GeV. Furthermore it shows that the application of this method in proton-proton collision at 500 GeV results in a dominant production of the b in comparison with c quark for the energy of non-photonic electron from the heavy _avor decay greater than 4. 3 GeV. The inclusive spectra of the charm particles (D0 and D*) has been measured by STAR in proton-proton minimum bias collisions in the range of pT up to 7 GeV/c. This thesis presents a new pioneering study on the D* measurement in High Tower dataset which allows to extend the spectra in pT up to 18 GeV/c in the protonproton system at 500 GeV. That range of the pT for D* meson has never been reached before on any system measured in STAR
Ben-Haim, Eli. "La fonction de fragmentation du quark b, du LEP au TeVatron". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2004. http://tel.archives-ouvertes.fr/tel-00010858.
Testo completoLe, Bris Nicolas. "Étude des décroissances semi-muoniques de saveurs lourdes à bas pt, et de l'éfficacité de trajectographie du spectromètre à muons d'ALICE". Nantes, 2009. http://www.theses.fr/2009NANT2065.
Testo completoIn accelerators as the one of LHC, collisions will help to reproduce the Quark Crluon Plasma. With such a purpose, the ALICE detector is optimized to study the transition toward this hypothetic state of matter. The ALICE’s muon spectrometer will measure the muon related probes (quarkonia, heavy flavours). The first part of this thesis presents the method to calculate the tracking efficiency of this spectrometer. The results, obtained by simulation, are placed in the global efliciency context. They show the evolution of the efliciency as a function of likely electronics failures. They establish that a proper working of the detector involves less than 10% of channels failures and 15% of missing so-called MANU cards. The second part presents the Distance Closest Approach method which enhance the identification of muons from charm and beauty particle decays. For momentum as for pt < 4 GeV/ c, the determination of heavy flavours contribution (charm in particular) in the single muon spectrum requires subtracting the decay part from pions and kaons. This discrimination is not possible track by track, an alternative method to subtract the light-hadrons has been developed. The DCA method uses the distance between the extrapolated track in the primary vertex transverse plan and the vertex itself. The different shapes of the distributions in DCA between the signal and the noise, arising from the different decay length path to the particle types, permit a better separation, and therefore a better estimation of the corresponding cross sections
Descotes-Genon, Sebastien. "Le rôle du quark étrange dans la brisure de la symétrie chirale". Habilitation à diriger des recherches, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00678960.
Testo completoLe, Bris Nicolas. "Étude des décroissances semi-muoniques de saveurs lourdes à bas Pt, et de l'efficacité de trajectographie du spectromètre à muons d'ALICE". Phd thesis, Université de Nantes, 2009. http://tel.archives-ouvertes.fr/tel-00464809.
Testo completoMalak, Rehan. "Contribution à l'ordre dominant de la polarisation hadronique du vide au moment magnétique anomal du muon en QCD sur réseau avec quatre saveurs de quarks à leur masse physique". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4089.
Testo completoThe anomalous magnetic moments of leptons have played an important role in the development of the Standard Model of particle physics. Today, that of the muon is measured very precisely and will be so with even higher precision in an experiment that will begin in 2017. To the extent that the theoretical prediction can be made with comparable uncertainties, a rigorous test of the Standard Model will be possible. Here we study the limiting factor in this prediction, the leading-order hadronic vacuum polarization contribution (HVP-LO). We compute this contribution numerically with a discretized version of the theory of the strong interaction: lattice Quantum Chromodynamics. High-performance computing allows to solve the theory in its highly nonlinear regime, which is the one most relevant here. The simulation algorithms and the methods used to obtain the HVP, as well as the associated statistical and systematic uncertainties, are described. These methods are then applied to simulations performed with the Budapest-Marseille-Wuppertal collaboration. First they are implemented in a dedicated study of finite-volume effects. The most robust methods are then used to compute the HVP with simulations which include N_f=2+1+1 flavors of quarks. These are performed directly at the physical values of the u, d, s and c quark masses, with six lattice spacings and in large volumes of 6 fm^3. They allow us to compute the HVP-LO contribution to the anomalous magnetic moment of the muon with controlled errors of around 3%
Defraigne, Tardieu Geneviève. "L'Université populaire Quart Monde : la construction du savoir émancipatoire". Paris 8, 2009. http://octaviana.fr/document/150984871#?c=0&m=0&s=0&cv=0.
Testo completoThe Fourth World People's University (FWPU) is a locus for collective expression that was founded in 1972 by Joseph Wresinski with very underprivileged people. It is a place for emancipation through the construction of knowledge. The People's University is built upon the experience-based knowledge of persons who live in extreme poverty. This dissertation examines how people who have been excluded from access to knowledge can start anew to learn, to produce knowledge, to act for their own emancipation. This participatory action research project explores : - the actions and thinking of movement founder Joseph Wresinski; - the concepts of extreme poverty, and of exclusion; - the history of people's universities; - and the concepts of learning process, of relationship to knowledge, and of emancipation. The thesis explores the works of practitioners of emancipation- P. Freire, S. Alinsky, D. Dolci- followed by the history and practices of the Fourth World People's University. The theoretical framework utilized is "communicative action" following J. Habermas and that of "self-teaching from personal experience" following J. Mezirow. The Fourth World People’s University is a locus for the creation of social relationships that include recognition, reciprocity and commitment to change. An existential action research following R. Barbier was undertaken with members of the Fourth World People's University. Members shed light on the conditions for the production of identity, meanings, and knowledge in operation at the FWPU, as well as for the production of new social relations. In this setting knowledge stemming from resiliency is produced as are the conditions for cognitive democracy, both of which are factors in social change
Vincent, P. "Mesure des rapports d'embranchement semi-leptoniques et de la contribution baryonique dans les desintegrations du quark b". Phd thesis, Université Claude Bernard - Lyon I, 1994. http://tel.archives-ouvertes.fr/in2p3-00002740.
Testo completoCharpy, Alexandre. "Etude de la production de muons issus des saveurs lourdes prédite par le modèle de Color Glass Condensate dans les collisions proton-proton et proton-plomb dans l'acceptance du spectromètre à muons de l'expérience ALICE du LHC". Phd thesis, Université Paris Sud - Paris XI, 2007. http://tel.archives-ouvertes.fr/tel-00188303.
Testo completopartonique dans le domaine des très petits x, domaine largement accessible au LHC. Le CGC présente un grand intérêt dans l'étude des collisions d'ions lourds ultra-relativistes plomb-plomb puisqu'elle permet d'en décrire les conditions initiales du système qui évoluera vers un état où les quarks et les gluons sont déconfinés : le Plasma de Quarks et de Gluons (PQG). ALICE est l'expérience du LHC dédiée à l'étude du PQG dont l'une des voies d'étude est la mesure de la production des quarkonia lourds à l'aide d'un spectromètre à muons. Couvrant un domaine de rapidité entre −4 < y < −2.5, ce dernier peut s'avérer particulièrement intéressant pour étudier le CGC.
La première partie de ce travail présente les tests de performances des chambres de trajectographie du spectromètre à muons équipées avec l'électronique d'acquisition finale CROCUS. Ils ont conduit à poser les bases du processus de calibration de l'électronique frontale. La seconde partie concerne des simulations effectuées sur
certains paramètres électroniques pouvant affecter les performances du spectromètre à muons. La dernière partie développe les prédictions du modèle du CGC pour la production de quarks lourds et la manifestation des effets de saturation via la mesure des muons issus de ces quarks.
Jamin, D. "Recherche du boson de Higgs du Modèle Standard dans le canal de désintégration ZH->nu nu bb sur le collisionneur Tevatron dans l'expérience D0. Développement d'une méthode d'étiquetage des jets de quark b avec des muons de basses impulsions transverses". Phd thesis, Université de la Méditerranée - Aix-Marseille II, 2010. http://tel.archives-ouvertes.fr/tel-00557839.
Testo completoHamon, Julien. "Etude de la production des mésons charmés-étranges dans les collisions proton-proton et proton-plomb avec l'expérience ALICE au LHC". Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAE012/document.
Testo completoThe study of the production of charm quarks in high-energy atomic-nucleus collisions offers an genuine approach for the study of the quark-gluon plasma. The understanding and characterisation of this state of deconfined-matter, at first sight created in heaviest systems, require a fine knowledge of lightest systems, such as proton-proton (pp) and proton-lead (p-Pb) collisions. In this manuscript, we present the measurement of the charm-strange mesons Ds+ production, at central rapidity, with the LHC run 2 data, collected in 2016 with the ALICE experiment. Two systems are studied: pp collisions at √s=13 TeV and p-Pb collisions at √sNN=5.02 TeV. The production cross-section of Ds+, their relative abundance and their nuclear modification factor are measured then compared to other measurements and to various theoretical predictions. The p-Pb result establishes a new reference for the study of Pb-Pb collisions
Zhang, Zuman. "Open heavy-flavour measurements via muons in proton-proton and nucleus-nucleus collisions with the ALICE detector at the CERN-LHC". Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC077/document.
Testo completoThe study of ultra-relativistic heavy-ion collisions aims at investigating a state of strongly-interacting matter at high energy density and temperature, the Quark-Gluon Plasma (QGP). Heavy quarks (charm and beauty) are predominantly produced in initial hard scattering processes during the early stage of the collisions and experience the full evolution of the medium. Therefore, the measurement of open heavy flavours should provide essential information on the QGP properties. Similar measurements in small systems are also essential for a comprehensible understanding of the QGP properties. The study of open heavy flavours in proton-proton (pp) collisions provides the mandatory reference for measurements in heavy-ion collisions. This thesis presents measurements of the production of muons from heavy-flavour hadron decays at forward rapidity (2.5 < y < 4) in pp collisions at sqrt (s) = 5.02 TeV, Pb-Pb collisions at sqrt (sNN) = 2.76 and 5.02 TeV and Xe-Xe collisions at sqrt (sNN) = 5.44 TeV collected with the ALICE detector at the CERN-LHC. The differential production cross sections of muons from heavy-flavour hadron decays in pp collisions at sqrt (s) = 5.02 TeV are obtained in a wide transverse momentum interval, 2 < pT < 20 GeV/c, and with an improved precision compared to the previously published measurements at sqrt (s) = 2.76 and 7 TeV. The measurements are described within uncertainties by predictions based on perturbative QCD. A strong suppression of the yield of muons from heavy-flavour decays is observed in the 10% most central Pb-Pb collisions at both sqrt (sNN) = 2.76 and 5.02 TeV. This suppression is due to final-state effects induced by the hot and dense medium. The suppression in Xe-Xe collisions is similar to that observed with Pb-Pb collisions. The comparison in the two colliding systems provides insight in the path-length dependence of medium-induced parton energy loss. The results constrain model calculations
Manceau, Loïc. "Mesure de la section efficace de production des hadrons lourds avec le spectromètre à muons d'ALICE au LHC". Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2010. http://tel.archives-ouvertes.fr/tel-00549229.
Testo completoFang, Bo. "Study of the Dₛ⁺ → ƞ'π⁺π⁻π⁺ decays at BESIII and precise measurement of the branching fraction of the B° → D*⁻τ⁺ν decay at LHCb". Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASP006.
Testo completoThe Standard model of particle physics requires lepton flavor universality, a property that the weak coupling constants have the same values for three generations of charged leptons. In recent decades, a long-standing anomaly in the measurement of R(D*), the ratio between B(B⁰ → D*⁻τ⁺ν) and B(B⁰ → D*⁻ℓ⁺ν) (ℓ = e, μ), implicates the violation of lepton flavor universality, of which the confirmation will prove the existence of new physics beyond standard model. The precision measurement of R(D*) provides an important probe for the possible new physics effect that is related to LFUV. Among all experimental measurements performed so far, the hadronic R(D*) analysis at LHCb, where the τ lepton is reconstructed from three charged pions, possesses the highest precision in single measurement. However, the most important physics background in that analysis, B → D*⁻Ds⁺ X(Ds⁺ → π⁺π⁻π⁺X) process, dominates the systematic uncertainties with ten times statistics to the signal decays in the final fit. So the studies of Ds⁺ decays to three charged pions will provide valuable information for separating the background hence reducing the systematic uncertainties, not only in the hadronic R(D*) analysis, but also in all researches involving hadronic τ decays. This thesis starts with a collective study of Ds⁺ decay phenomenology focusing on Ds⁺ → π⁺π⁻π⁺X decays, followed by the first observation of Ds⁺ → η′π⁺π⁻π⁺ mode and measurement of its branching fraction at BESIII experiment. Finally, these information of Ds⁺ → π⁺π⁻π⁺X decays are used to improve the R(D*) measurement, with the full Run 2 dataset collected by the LHCb detector. The Ds⁺ → η′π⁺π⁻π⁺ decay is searched for by using e⁺e⁻ annihilation data corresponding to a total integrated luminosity of 6.32 fb⁻¹, collected by BESIII detector at center-of-mass energies between 4178 and 4226 MeV. After considering systematic uncertainties, the decay mode of Ds⁺ → η′π⁺π⁻π⁺ is observed for the first time with a significance of 5.5σ. Possible intermediate processes of the decay Ds⁺ → η′π⁺π⁻π⁺ are also studied, but no conclusion is addressed due to limit of statistics. The branching fraction of Ds⁺ → η′π⁺π⁻π⁺ decay mode is measured to be B(Ds⁺ → η′π⁺π⁻π⁺) = (6.9 ± 1.6 ± 0.7) × 10⁻³. The value of R(D*) is measured with pp collision data samples collected from 2015 to 2018 by LHCb detector at center-of-mass energies of 13 TeV. The corresponding integrated luminosity is 6 fb⁻¹. The branching fraction of B⁰ → D*⁻τ⁺ν is measured relative to that of B⁰ → D*⁻π⁺π⁻π⁺ using hadronic τ⁺ → π⁺π⁻π⁺(π⁰)ν decays: B(B⁰ → D*⁻τ⁺ν )/B(B⁰ → D*⁻π⁺π⁻π⁺) with a record relative statistical accuracy of 3.9%
Crochet, Philippe. "Etude des collisions d'ions lourds aux énergies du SIS et du LHC". Habilitation à diriger des recherches, Université Blaise Pascal - Clermont-Ferrand II, 2005. http://tel.archives-ouvertes.fr/tel-00011353.
Testo completoA basse énergie, les collisions d'ions lourds permettent de sonder la matière nucléaire modérément chaude à grande densité baryonique.
A haute énergie, la chromodynamique quantique prédit le déconfinement des constituants des hadrons en un plasma de quarks et de gluons.
La première partie de ce document est consacrée à l'étude de la production d'étrangeté dans les collisions d'ions lourds aux énergies du SIS avec le détecteur FOPI installé au GSI.
La deuxième partie de ce document est consacrée à l'étude de la production des saveurs lourdes dans les collisions d'ions lourds aux énergies du LHC avec le détecteur ALICE installé au CERN.
Daussy-Renaudin, Victor. "Probing Lepton Flavour Universality through semitauonic Λb decays using three-pions τ-lepton decays with the LHCb experiment at CERN". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS335/document.
Testo completoProbing Lepton Flavour Universality has been recently a very promising topic to test for the presence of New Physics contributions in Standard Model processes. Measurements involving semitauonic decays are interesting as potential New Physics couplings to the τ-lepton could be enhanced with respect to the two other leptons due to its mass. Experimental measurements of B->D*τν and B->Dτν branching fractions are currently in tension with theoretical predictions at the 3.78σ level. Both precise measurements and analyses of new channels are thus required to understand the source of this disagreement. The work presented in this thesis describes the use of a new technique to reconstruct τ-lepton using its decay into three pions and its use to measure ratios of branching fractions for two decays B->D*τν and Λb->Λcτν with respect to the same decays involving a muon, these ratios are referred to as R(D*) and R(Λc). Using the 3 fb⁻¹ of proton-proton collisions recorded by the LHCb detector during the LHC Run1 at a centre-of-mass energy of 7 and 8 TeV, R(D*) was measured using the three-pions reconstruction for the τ to be R(D*⁻) = 0.291 ± 0.019(stat) ± 0.026(syst) ± 0.013(ext) This result is compatible with the Standard Model expectation at the 1σ level and is consistent with previous measurements. Its precision is able to slightly enforce the disagreement between the combination of the measurements with the theoretical prediction. The same dataset is also analysed in this thesis to study the Λb->Λcτν decay which is observed for the first time with a significance of 5.7σ. Both statistical and systematic uncertainties were estimated and R(Λc) can then be expressed as R(Λc) = X*(1 ± 0.105(stat) ± 0.162(syst) ± 0.12(ext)) with its central value remaining blind at the moment
Demeure, Marianne. "Les pédagogies émancipatrices dans le cadre des Universités populaires : le cas des Universités populaires de Paris 8 et Quart Monde". Electronic Thesis or Diss., Paris 8, 2019. http://www.theses.fr/2019PA080006.
Testo completoThis research on two singular popular Universities attempts to analyze in depth the effects of the pedagogies used by these two popular Universities. Inspired by three pedagogues, for the popular University of Paris VIII (U2p8): Paulo Freire, Henri Desroche and Célestin Freinet and for the Fourth World People's University: Paulo Freire, Saül Alinsky and Danilo Dolci, the characteristics of these approaches are analyzed and crossed. Paulo Freire represents a common point in the pedagogical approach of the two popular Universities, his life, his works, his ideas are therefore particularly highlighted here. The U2p8 uses life stories, writing workshops with the help of a tutor and postgraduate research methods; the Fourth World People's University uses the experience of participants in extreme poverty to build emancipatory knowledge, which enables society to recognize their identity. The individual and collective dimensions are different in the two popular Universities. By inscribing these two popular Universities in a historical context, we see how these two popular Universities use the experience, although different in certain points, several points bring them together. The feedback from the participants allowed us to see the effects produced by these two popular Universities, particularly on the relationship to knowledge. A multireferential point of view will allow us to analyze the two popular Universities in five perspectives
Boyer, Bruno. "Etude des J/psi dans le canal dimuon du spectromètre de l'expérience ALICE auprès du LHC dans les collisions proton+proton à sqrt(s) = 7 TeV". Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00662272.
Testo completoVallier, Alexis. "Measurement of the CKM angle gamma in the B⁰->DK*⁰ decays using the Dalitz method in the LHCb experiment at CERN and photon reconstruction optimisation for the LHCb detector upgrade". Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112175/document.
Testo completoQuark mixing is described in the standard model of particle physics with the Cabibbo-Kobayashi-Maskawa mecanism. The angle gamma of the unitarity triangle is one of the parameters of this mecanism that is still determined with a large uncertainty. It can be measured without significant contribution of new physics, making it a standard model key measurement. The current precision of the best direct measurement of gamma is approximately 10°, whereas the global fits of the CKM parameters determine this angle up to a few degrees. Therefore precise measurement of this quantity is needed to further constrain the Unitarity Triangle of the CKM matrix, and check the consistency of the theory. This thesis reports a measurement of gamma with a Dalitz analysis of the B0->DK*0 channel where the D meson decays into K0Spipi, based on the 3 fb⁻¹ of proton-proton collision data collected by LHCb during the LHC Run I, at the centre-of-mass energy of 7 and 8 TeV. This channel is sensitive to gamma through the interference between the b->u and b->c transitions. The CP violation observables are measured to be x- = -0.09 ^{+0.13}_{-0.13} ± 0.09 ± 0.01 , x+ = -0.10 ^{+0.27}_{-0.26} ± 0.06 ± 0.01 , y- = 0.23 ^{+0.15}_{-0.16} ± 0.04 ± 0.01 , y+ = -0.74 ^{+0.23}_{-0.26} ± 0.07 ± 0.01 , where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is the systematic uncertainty due to the Dalitz model. A frequentist interpretation of these observables leads to rB0 = 0.39±0.13 , deltaB0 = ( 186^{+24}_{-23} )°, gamma = ( 77^{+23}_{-24} )° , where rB0 is the magnitude of the ratio between the suppressed and favoured decays and deltaB0 the strong phase difference between these two decays. In addition, the work performed on the optimisation of the photon reconstruction for the upgraded LHCb detector is reported. During LHC Run III, the LHCb instantaneous luminosity will be increased by a factor five, implying a larger shower overlap in the electromagnetic calorimeter. The study shows that reducing the cluster size used in the photon reconstruction limits the effect of the overlap between the showers, without inducing a significant energy leakage. With some dedicated corrections, the new cluster reconstruction improves the Bs->Phi gamma mass resolution by 7 to 12%, depending on the calorimeter region
Baalouch, Marouen. "Dalitz analysis of the three-body charmless decay B0 → K0Sπ+π− with the LHCb spectrometer". Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22652/document.
Testo completoStudies of charmless three-body decays of the neutral B mesons with a K0S in the final state are presented in this thesis. The analyses are performed with the full statistics recorded by the LHCb spectrometer during the Run I of the LHC. The amplitude analysis of the decay B0→K0Sπ+π− represents the main part of this thesis analysis. A time-integrated untagged Dalitz-Plot analysis of the decay is performed. The fit fractions of the quasi-two-body decays are obtained. Likewise, the direct CP asymmetries of the quasi-two-body decays B0→K*+(892)π−, B0→K0*+(1430)π−, B0→K2*+(1430)π− and B0→f0(980)K0S are obtained. The largest sensitivity is obtained for ACP (B0→K*+(892)π−). This measurement is the first observation of the CP asymmetry with a significance larger then five standard deviations. The measurement is in agreement with the world average, with an improved precision