A Search for the Rare Decay B -] Pi Ll−


Book Description

This thesis presents a search for the rare B meson decay B -> pi ll− (l=e or mu) using 428 fb−1 of data collected at the Upsilon(4S) resonance by the BaBar detector at the PEP-II asymmetric energy ee− storage rings located located at SLAC National Accelerator Laboratory in Menlo Park, California. Four exclusive modes are studied: B+ -> pi+ e+e−, B+ -> pi+ mu+mu−, B0 -> pi0 e+e−, and B0 -> pi0 mu+mu−. Branching fraction upper limits at the 90% confidence level are presented for the exclusive modes B+ -> pi+ mu+mu− and B0 -> pi0 mu+mu−, and the combined mode B -> pi mu+mu−.




Search for the Rare Decay B to Pi L+ L-


Book Description

The authors have performed a search for the flavor-changing neutral-current decays B →?ll−, where l+l− is either e+e− or?+?−, using a sample of 230 million?(4S) → B{bar B} decays collected with the BABAR detector. They observe no evidence of a signal and measure the upper limit on the isospin-averaged branching fraction to be?(B →?l+l−)




Search for the Rare Decay B to Pi L+ L-


Book Description

The authors present results of a search for the rare flavor-changing neutral-current decay B {yields} {pi}{ell}{sup +}{ell}{sup -}, based on a data sample corresponding to 209 fb{sup -1} of integrated luminosity collected with the BABAR detector at the PEP-II B Factory. They reconstruct the four exclusive B decay modes B{sup +} {yields} {pi}{sup +}{ell}{sup +}{ell}{sup -} and B{sup 0} {yields} {pi}{sup 0}{ell}{sup +}{ell}{sup -}, where {ell} is either an e or {mu}. They find no evidence for a signal, and they obtain the upper limit at 90% confidence level on the lepton-flavor-averaged branching fraction to be {Beta}(B{sup +} {yields} {pi}{sup +}{ell}{sup +}{ell}{sup -}) = 2 x {tau}B{sup +}/{tau}B{sup 0} {Beta}(B{sup 0} {yields} {pi}{sup 0}{ell}{sup +}{ell}{sup -})




The Search for the Rare Decay B to A0+pi0


Book Description

A search for the decay B{+-} {yields} a{sub 0}{sup {+-}}{pi}{sup 0} with the a{sub 0}{sup +} decaying to an {eta} and a {pi}{sup +} was carried out at the Stanford Linear Accelerator Center using the BABAR detector coupled with the PEP-II collider. The analysis used a data sample comprised of approximately 252 million B{bar B} pairs collected at the {Upsilon}(4S) resonance. No signal was observed and a 90% confidence level upper limit on the branching fraction was set at 1.32 x 10{sup -6}.
















B Physics & Cp Violation '99, 3rd Intl Conf


Book Description

CP violation was first observed in 1964, but only in 1999 did we gain much greater experimental insight. Direct CP violation finally appeared in the form of ε′/ε in the K system. Indirect CP violation in B → J/Ψ Ks decay, the raison d'être for construction of e+e- B factories, was first sniffed out at the proton-antiproton collider. The asymmetric B factories — BABAR at SLAC and BELLE at KEK — were completed, while the symmetric B factory at Cornell was upgraded to CLEO-III. It seems that everyone is positioning himself for the great competition on “B Physics and CP Violation”, racing to unravel the Kobayashi-Maskawa matrix, especially the size and origin of CP phases. The change of millennium provides a dramatic backdrop.To have intensive discussions at the technical level, to create broader interest in the subject, and to maximize interaction between experimenters and theorists, this book starts with the status of B factories: accelerator, detector and physics analysis. Following an overview of B physics and the CKM matrix, it delves into the details of lifetime, spectroscopy and decays, with even more specialized discussions on rare decays, direct and indirect CP violation, factorization and final state interactions, determination of unitarity phases, etc. Topics on ε′/ε, rare K decay, charm and hyperon systems, and various T, CP and CPT tests are also discussed at length. The book closes with the outlook for hadron machines and the prospects for new physics. A special feature is that there are two summary talks, one on experiment and the other on theory. The book is further augmented by two dozen excellent contributed talks.