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The Super Flavor Factory

Description: The main physics goals of a high luminosity e{sup +}e{sup -} flavor factory are discussed, including the possibilities to perform detailed studies of the CKM mechanism of quark mixing, and constrain virtual Higgs and Non-Standard Model particle contributions to the dynamics of rare B{sub u,d,s} decays. The large samples of D mesons and {tau} leptons produced at a flavor factory will result in improved sensitivities on D mixing and lepton flavor violation searches, respectively. One can also test fundamental concepts such as lepton universality to much greater precision than existing constraints and improve the precision on tests of CPT from B meson decays. Recent developments in accelerator physics have demonstrated the feasibility to build an accelerator that can achieve luminosities of {Omicron}(10{sup 36} cm{sup -2} s{sup -1}).
Date: January 26, 2007
Creator: Bevan, A.J. & /Queen Mary, U. of London
Partner: UNT Libraries Government Documents Department

Search for Lepton Flavour Violating Decays tau- to l- Ks with the BaBar experiment

Description: A search for the lepton flavor violating decays {tau}{sup -} {yields} l{sup -} K{sub S}{sup 0} (l = e or {mu}) has been performed using a data sample corresponding to an integrated luminosity of 469 fb{sup -1}, collected with the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} asymmetric energy collider. No statistically significant signal has been observed in either channel and the estimated upper limits on branching fractions are {Beta}({tau}{sup -} {yields} e{sup -} K{sub S}{sup 0}) < 3.3 x 10{sup -8} and {Beta}({tau}{sup -} {yields} {mu}{sup -}K{sub S}{sup 0}) < 4.0 x 10{sup -8} at 90% confidence level.
Date: January 6, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E. et al.
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

Dalitz Plot Analysis of Ds+->pi+pi-pi+

Description: A Dalitz plot analysis of {approx} 13, 000 D{sub s}{sup +} decays to {pi}{sup +}{pi}{sup +}{pi}{sup -} has been performed. A 384 fb{sup -1} data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring running at center of mass energies near 10.6 GeV, is used. Amplitudes and phases of the intermediate resonances which contribute to this final state are measured. A high precision measurement of the ratio: {Beta}(D{sub s}{sup +} {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -})/{Beta}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) = 0.199 {+-} 0.004 {+-} 0.006 is performed. Using a model independent partial wave analysis the amplitude and phase of the S-wave have been measured.
Date: January 26, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department

Searches for the Decays B0 to l+- tau-+ and B+ to l+ nu(L=e,mu) using Hadronic Tag Reconstruction

Description: We present searches for the leptonic decays B{sup +} {yields} {ell}{sup +}{nu} and the lepton flavor violating decays B{sup 0} {yields} {ell}{sup {+-}}{tau}{sup {-+}}, where {ell} = e, {mu}, with data collected by the BABAR experiment at SLAC. This search demonstrates a novel technique in which we fully reconstruct the accompanying {bar B} in {Upsilon}(4S) {yields} B{bar B} events, and look for a monoenergetic lepton from the signal B decay. The signal yield is extracted from a fit to the signal lepton candidate momentum distribution in the signal B rest frame. Using a data sample of approximately 378 million B{bar B} pairs (342 fb{sup -1}), we find no evidence of signal in any of the decay modes. Branching fraction upper limits of {Beta}(B{sup +} {yields} e{sup +}{nu}) < 5.2 x 10{sup -6}, {Beta}(B{sup +} {yields} {mu}{sup +}{nu}) < 5.6 x 10{sup -6}, {Beta}(B{sup 0} {yields} e{sup +}{tau}{sup -}) < 2.8 x 10{sup -5} and {Beta}(B{sup 0} {yields} {mu}{sup +}{tau}{sup -}) < 2.2 x 10{sup -5}, are obtained at 90% confidence level.
Date: January 30, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X. et al.
Partner: UNT Libraries Government Documents Department