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CDF B spectroscopy results: B** and Bc{sup +}

Description: The authors report on two spectroscopy results from CDF. First, they observe the orbitally excited B** mesons in B {r_arrow} {ell}D(*) X events. They find 28 {+-} 6 {+-} 3% of light B mesons produced are B** states. A collective mass fit results in a B{sub 1} mass of 5.71 {+-} 0.02 GeV/c{sup 2}. Secondly, they observe 20.4{sub {minus}5.5}{sup +0.18} {+-} 0.03 ps lifetime. The production rate is in reasonable accordance with expectations.
Date: September 8, 1999
Creator: Bauer, G.
Partner: UNT Libraries Government Documents Department

B Decays as a probe of spontaneous cp-violation in SUSY models

Description: We consider phenomenological implications of susy models with spontaneously broken CP-symmetry. In particular, we analyze CP-asymmetries in B decays and find that the predictions of these models are vastly different from those of the SM. These features are common to NMSSM-like models with an arbitrary number of sterile superfields and the MSSM with broken R-parity.
Date: July 8, 1999
Creator: Lebedev, Oleg
Partner: UNT Libraries Government Documents Department

Unraveling the Structure of Hadrons with Effective Field Theories of QCD

Description: Effective Field theory is a powerful framework based on controlled expansions for problems with a natural separation of energy scales. This technique is particularly important for QCD, the theory of strong interactions, due to the vast diversity of phenomena that it describes. Stewart and collaborators have invented a new class of effective theories that can be used in processes with energetic hadrons. These Soft-Collinear Effective Theories provide a unified framework for describing hadronic processes which involve hard probes or the release of a large amount of energy. Many interesting issues about hadronic physics can be addressed with the soft-collinear effective theory. Examples include the size and shape of hadronic form factors, the universality of hadronic distribution functions for a plethora of processes, and the importance of subleading corrections at intermediate energy scales. Effective field theories allow these issues to be addressed using only the underlying symmetries and scales in QCD. Understanding these issues also has a direct impact on other areas of physics, such as on devising clean methods for the measurement of CP violation in the decay of B-mesons. Current progress on the soft-collinear effective theory and related methods is discussed in this report.
Date: June 8, 2004
Creator: Stewart, Iain
Partner: UNT Libraries Government Documents Department

Measurement of the Branching Fraction for the DecayB^{\pm} to K^{*\pm} gamma, K^{*\pm} toK^{\pm} \pi^{0} with the BaBar Detector

Description: The branching fraction of the radiative penguin B meson decay B{sup {+-}} {yields} K*{sup {+-}}{gamma} is measured at the PEP-II asymmetric energy e{sup +}e{sup -} collider, operating at a center of momentum energy of 10.58 GeV, the {Upsilon}(4S) resonance. This document concentrates on the case K*{sup {+-}} {yields} K{sup {+-}}{pi}{sup 0}; {pi}{sup 0} {yields} {gamma}{gamma}. This analysis is based on a dataset of 88.2-million {Upsilon}(4S) {yields} B{bar B} events corresponding to 81.3 fb{sup -1} collected with the BABAR detector.
Date: September 8, 2006
Creator: koeneke, K.
Partner: UNT Libraries Government Documents Department

Electro-Weak Penguin and Leptonic Decays in BaBar

Description: Electro-weak penguin and leptonic decays provide an indirect probe for physics beyond the Standard Model and contribute to the determination of Standard Model parameters. Copious quantities of B mesons produced at the B-Factories permit precision measurements of the electro-weak penguin decays and searches for leptonic decays. We review the current experimental status of b {yields} s(d){gamma}, B{sup 0} {yields} D*{sup 0}{gamma}, b {yields} s{ell}{sup +}{ell}{sup -} and finally B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}} decays at BABAR.
Date: September 8, 2005
Creator: Di Lodovico, F. & /Queen Mary, U. of London
Partner: UNT Libraries Government Documents Department

The Search for B+ to Tau+ Nu(Tau) at BaBar

Description: We present a search for the decay B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}} using 288 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed semileptonic B decay (B{sup -} {yields} D{sup o}{ell}{sup -}{bar {nu}}{sub {ell}}X) is selected, and in the recoil a search for B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}} signal is performed. The {tau} is identified in the following channels: {tau}{sup +} {yields} e{sup +}{nu}{sub e}{bar {nu}}{sub {tau}}, {tau}{sup +} {yields} {mu}{sup +} {nu}{sub {mu}}{bar {nu}}{sub {tau}}, {tau}{sup +} {yields} {pi}{sup +}{pi}{sup 0}{bar {nu}}{sub {tau}}. We measure a branching fraction of {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) = 0.88{sub -0.67}{sup +0.68}(stat.) {+-} 0.11(syst.) x 10{sup -4} and extract an upper limit on the branching fraction, at the 90% confidence level, of {Beta}(B{sup +} {yields} {tau}{sup +}{nu}{sub {tau}}) < 1.8 x 10{sup -4}. We calculate the product of the B meson decay constant and |V{sub ub}| to be f{sub B} {center_dot} |V{sub ub}| = (7.0{sub -3.6}{sup +2.3}(stat.){sub -0.5}{sup +0.4}(syst.)) x 10{sup -4} GeV.
Date: January 8, 2007
Creator: Corwin, L.A.
Partner: UNT Libraries Government Documents Department

A Measurement of the Branching Fractions ofexclusive Bbar to D(*)(pi)lnu Decays in Events with a Fully Reconstructed BMeson

Description: The authors report a measurement of the branching fractions for {bar B} {yields} D{sup (*)}{pi}{ell}{sup -}{bar {nu}}{sub {ell}} decays based on 341.1 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. The obtain {Beta}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.33 {+-} 0.09{sub stat.} {+-} 0.09{sub syst.})%, {Beta}(B{sup -} {yields} D*{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = 5.83 {+-} 0.15{sub stat.} {+-} 0.30{sub syst.}%, {Beta}({bar B}{sup 0} {yields} D{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.21 {+-} 0.11{sub stat.} {+-} 0.12{sub syst.})% {Beta}({bar B}{sup 0} {yields} D*{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = 5.49 {+-} 0.16{sub stat.} {+-} 0.25{sub syst.}%, {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.42 {+-} 0.06{sub stat.} {+-} 0.03{sub syst.})%, {Beta}(B{sup -} {yields} D*{sup +} {pi}{sup -}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.59 {+-} 0.05{sub stat.} {+-} 0.04{sub syst.})%, {Beta}({bar B}{sup 0} {yields} D{sup 0}{pi}{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.43 {+-} 0.08{sub stat.} {+-} 0.03{sub syst.})% and {Beta}({bar B}{sup 0} {yields} D*{sup 0} {pi}{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.48 {+-} 0.08{sub stat.} {+-} 0.04{sub syst.})%.
Date: January 8, 2008
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Results from the B Factories

Description: These proceedings are based on lectures given at the Helmholtz International Summer School Heavy Quark Physics at the Bogoliubov Laboratory of Theoretical Physics, Dubna, Russia, during August 2008. I review the current status of CP violation in B meson decays from the B factories. These results can be used, along with measurements of the sides of the Unitarity Triangle, to test the CKM mechanism. In addition I discuss experimental studies of B decays to final states with 'spin-one' particles.
Date: January 8, 2009
Creator: Bevan, A. & /Queen Mary, U. of London
Partner: UNT Libraries Government Documents Department

Bounds on the mixing of the down-type quarks with vector-like singlet quarks

Description: We derive bounds on the mixing of the standard charge -1/3 quarks with vector-like isosinglet quarks, as they exist in some extensions of the standard model. We make no assumptions about the unitarity or any other features of the mixing matrix. We find that the mixing is quite constrained: we are able to set bounds on all the extra parameters which arise in the mixing matrix (CKM matrix), except on two phases. The assumption that there exists only one exotic quark leads to some extra relationships among the parameters of the mixing matrix.
Date: September 8, 1992
Creator: Lavoura, L. & Silva, J.P.
Partner: UNT Libraries Government Documents Department

Bounds on the mixing of the down-type quarks with vector-like singlet quarks

Description: We derive bounds on the mixing of the standard charge -1/3 quarks with vector-like isosinglet quarks, as they exist in some extensions of the standard model. We make no assumptions about the unitarity or any other features of the mixing matrix. We find that the mixing is quite constrained: we are able to set bounds on all the extra parameters which arise in the mixing matrix (CKM matrix), except on two phases. The assumption that there exists only one exotic quark leads to some extra relationships among the parameters of the mixing matrix.
Date: September 8, 1992
Creator: Lavoura, L. & Silva, J. P.
Partner: UNT Libraries Government Documents Department