Mesure DE La Section Efficace DE Production DE Paires DE Quarks Top Dans L'Etat Final DI-Electron Avec Les Donnees Collectees Par L'Experience d0 AU Runiia (open access)

Mesure DE La Section Efficace DE Production DE Paires DE Quarks Top Dans L'Etat Final DI-Electron Avec Les Donnees Collectees Par L'Experience d0 AU Runiia

The top quark has been discovered in 1995 by CDF and D0 collaborations in proton-antiproton collisions at the Tevatron. The amount of data recorded by both experiments makes it possible to accurately measure the properties of this very massive quark. This thesis is devoted to the measurement of the top pair production cross-section via the strong interaction, in a final state composed of two electrons, two particle jets and missing transverse energy. It is based on a 1 fb{sup -1} data set collected by the D0 experiment between 2002 and 2006. The reconstruction and identification of electrons and jets is of major importance in this analysis, and have been studied in events where a Z boson is produced together with one or more jets. The Z+jets process is indeed the dominant physics background to top pair production in the dielectron final state. The primary goal of this cross-section measurement is to verify Standard Model predictions. In this document, this result is also interpreted to indirectly extract the top quark mass. Moreover, the cross-section measurement is sensitive to new physics such as the existence of a charged Higgs boson. The selection established for the cross-section analysis has been used to search …
Date: September 1, 2008
Creator: Martin Dit Latour, Bertrand & /LPSC, Grenoble
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Study of correlations between photoproduced pairs of charmed particles at Experiment E831/FOCUS (open access)

Study of correlations between photoproduced pairs of charmed particles at Experiment E831/FOCUS

The authors present the study of the charm-pair correlations produced in photon-nucleon interactions at <E{sub {gamma}}> = 175 GeV/c, by the Fermilab fixed target experiment E831/FOCUS. The E831/FOCUS experiment produced and reconstructed over one million charm particles. This high statistics allows the reconstruction of more than 7000 charm-pair mesons D{bar D}, 10 times the statistic of former experiments, and also allows to get, for the first time, about 600 totally reconstructed charm-pairs in the DD{sub s} and D{Lambda}{sub c} channels. They were able to study, with some detail, the kinematical correlations between the charm and anticharm particle forming a pair, in the square transverse momentum (p{sub T}{sup 2}), azimuthal angle difference ({Delta}{phi}), rapidity difference ({Delta}y) and the charm-pair mass variables. They observe some correlation for the longitudinal momenta, and a significant correlation for the transverse momenta of the charm and anticharm particles. They compare the experimental distributions with theoretical predictions based on the photon-gluon fusion model (PGF), for the production of c{bar c} quarks, and the standard Lund hadronization model. These models are implemented by the PYTHIA Monte Carlo event generator. The PYTHIA program allows the inclusion, in the simulation, of non-perturbative effects that have been shown to be important …
Date: August 1, 2008
Creator: Castromonte Flores, Cesar Manuel & /Rio de Janeiro, CBPF
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Mesure de l'angle Gamma du triangle d'unitarit_ de la matrice CKM dansles d_sint_grations B to D*K aupr_s de l'exp_rience BaBaR (open access)

Mesure de l'angle Gamma du triangle d'unitarit_ de la matrice CKM dansles d_sint_grations B to D*K aupr_s de l'exp_rience BaBaR

None
Date: April 29, 2008
Creator: Latour, Emmanuel & Polytechnique, /Ecole
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Mesure DU Rapport D'Embranchement ET DU Facteur Deforme DE La D_Sint_Gration b0 to Pilnu, ET D_Termination DE |Vub| Avec Unetechnique DE Reconstruction Rel_Ch_E DU Neutrinoac (open access)

Mesure DU Rapport D'Embranchement ET DU Facteur Deforme DE La D_Sint_Gration b0 to Pilnu, ET D_Termination DE |Vub| Avec Unetechnique DE Reconstruction Rel_Ch_E DU Neutrinoac

The authors report the results of a study of the exclusive charmless semileptonic decay, B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}, undertaken with approximately 227 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with an innovative loose neutrino reconstruction technique. They obtain partial branching fractions in 12 bins of q{sup 2}, the momentum transfer squared, from which they extract the f{sub +}(q{sup 2}) form-factor shape and the total branching fraction {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.46 {+-} 0.07{sub stat} {+-} 0.08{sub syst}) x 10{sup -4}. Based on a recent unquenched lattice QCD calculation of the form factor in the range q{sup 2} > 16 GeV{sup 2}/c{sup 4}, they find the magnitude of the CKM matrix element |V{sub ub}| to be (4.1 {+-} 0.2{sub stat} {+-} 0.2{sub syst{sub -0.4}{sup +0.6}FF}) x 10{sup -3}, where the last uncertainty is due to the normalization of the form factor.
Date: July 17, 2007
Creator: Cote, David & U., /Montreal
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Measurement of the Production Cross Section of Top Quark Pairs in the Lepton + Jets Channel at d0 and Atlas and Interpretation in Terms of Charged Higgs Boson at Atlas (open access)

Measurement of the Production Cross Section of Top Quark Pairs in the Lepton + Jets Channel at d0 and Atlas and Interpretation in Terms of Charged Higgs Boson at Atlas

None
Date: May 1, 2007
Creator: Chevallier, Florent & /LPSC, Grenoble
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Study of CP Symmetry Violation in the Charmonium-K*(892) Channel By a Complete Time Dependent Angular Analysis (BaBar Experiment) (open access)

Study of CP Symmetry Violation in the Charmonium-K*(892) Channel By a Complete Time Dependent Angular Analysis (BaBar Experiment)

This thesis presents the full-angular time-dependent analysis of the vector-vector channel B{sub d}{sup 0} {yields} J/{psi}(K{sub S}{sup 0}{pi}{sup 0})*{sup 0}. After a review of the CP violation in the B meson system, the phenomenology of the charmonium-K*(892) channels is exposed. The method for the measurement of the transversity amplitudes of the B {yields} J/{psi}K*(892), based on a pseudo-likelihood method, is then exposed. The results from a 81.9 fb{sup -1} of collected data by the BABAR detector at the {Upsilon}(4S) resonance peak are |A{sub 0}|{sup 2} = 0.565 {+-} 0.011 {+-} 0.004, |A{sub {parallel}}|{sup 2} = 0.206 {+-} 0.016 {+-} 0.007, |A{sub {perpendicular}}|{sup 2} = 0.228 {+-} 0.016 {+-} 0.007, {delta}{sub {parallel}} = -2.766 {+-} 0.105 {+-} 0.040 and {delta}{sub {perpendicular}} = 2.935 {+-} 0.067 {+-} 0.040. Note that ({delta}{sub {parallel}}, {delta}{sub {perpendicular}}) {yields} (-{delta}{sub {parallel}}, {pi} - {delta}{sub {perpendicular}}) is also a solution. The strong phases {delta}{sub {parallel}} and {delta}{sub {perpendicular}} are at {approx}> 3{sigma} from {+-}{pi}, signing the presence of final state interactions and the breakdown of the factorization hypothesis. The forward-backward analysis of the K{pi} mass spectrum revealed the presence of a coherent S-wave interfering with the K*(892). It is the first evidence of this wave in the …
Date: September 18, 2006
Creator: T'Jampens, Stephane & /Orsay
Object Type: Report
System: The UNT Digital Library
Measurement of the inclusive jet cross section at D0 Run II (open access)

Measurement of the inclusive jet cross section at D0 Run II

None
Date: December 1, 2004
Creator: Agram, Jean-Laurent & /Haute Alsace U., GRPHE
Object Type: Thesis or Dissertation
System: The UNT Digital Library
International Journal of Government Auditing, July 2000, Vol. 27, No. 3 (French Version) (open access)

International Journal of Government Auditing, July 2000, Vol. 27, No. 3 (French Version)

Other written product issued by the General Accounting Office with an abstract that begins "This journal of the International Organization of Supreme Audit Institutions (INTOSAI) includes articles regarding: (1) the Food and Agriculture Organization's audit, management, and governance; (2) fighting corruption and fraud; (3) INTOSAI's conference on internal controls; (4) Romania's Court of Audit; (5) reports in print on auditing; and (6) activities inside INTOSAI."
Date: July 1, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
International Journal of Government Auditing, April 2000, Vol. 27, No. 2 (French Version) (open access)

International Journal of Government Auditing, April 2000, Vol. 27, No. 2 (French Version)

Other written product issued by the General Accounting Office with an abstract that begins "This French-language edition of the Journal of the International Organization of Supreme Audit Institutions (INTOSAI) includes articles concerning (1) auditing in the South Pacific, (2) new training infrastructure in the Asian Organization of Supreme Audit Institutions, (3) national responsibilities and and international activities of selected Supreme Audit Institutions, (4) the office of the Auditor General of Mexico, (5) reports in print, and (6) activities within INTOSAI."
Date: April 1, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
International Journal of Government Auditing, January 2000, Vol. 27, No. 1 (French Version) (open access)

International Journal of Government Auditing, January 2000, Vol. 27, No. 1 (French Version)

Other written product issued by the General Accounting Office with an abstract that begins "This is the French-language edition of the journal of the International Organization of Supreme Audit Institutions (INTOSAI) includes articles regarding: (1) issues concerning auditing in the new century as discussed at the 17th Commonwealth Auditors-General Conference held in Sun City, South Africa in October 1999; (2) efforts to encourage public health services, public works, and technical assistance at the Organization of African Supreme Audit Institutions' 8th General Assembly held in Burkina Faso in October 1999; (3) discussions held by the Organization of Latin American and Caribbean Supreme Audit Institutions' 9th General Assembly in Paraguay; (4) an audit profile on Sierra Leone; and (5) activities within INTOSAI."
Date: January 1, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library