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Title: Study of the Rare Decay B Mesons Decaying to X Mesons Positive And Negative Leptons at BABAR

Abstract

Flavor-changing neutral current transitions are forbidden at tree level in the Standard Model and can only occur via higher order diagrams. Since the amplitudes for such loops are dominated by the heaviest known particles, and non-SM effects are expected to contribute at the same order as the SM, such processes are an ideal place to look for new physics. We present a measurement of the inclusive branching fraction for the flavor-changing neutral current process B {yields} X{sub s}{ell}{sup +}{ell}{sup -} with a sample of 81.9 fb{sup -1}, collected with the BABAR detector at the Stanford Linear Accelerator Center. The final state is reconstructed from e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -} pairs and a hadronic system consisting of one K{sup {+-}} or K{sub s} and up to two pions, with at most one {pi}{sup 0}. They observe a signal of 40 {+-} 10(stat) {+-} 2(syst) events and extract a branching fraction {Beta}(B {yields} X{sub s}{ell}{sup +}{ell}{sup -}) = (5.6 {+-} 1.5(stat) {+-} 0.6(exp. syst) {+-} 1.1(model syst)) x 10{sup -6} for m{sub ll} > 0.2 GeV.

Authors:
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
878791
Report Number(s):
SLAC-R-776
TRN: US0602587
DOE Contract Number:  
AC02-76SF00515
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; AMPLITUDES; B MESONS; DECAY; LEPTONS; MESONS; NEUTRAL CURRENTS; PHYSICS; PIONS; STANDARD MODEL; STANFORD LINEAR ACCELERATOR CENTER; Experiment-HEP,HEPEX

Citation Formats

Koptchev, Ventzislav B, and /Massachusetts U., Amherst. Study of the Rare Decay B Mesons Decaying to X Mesons Positive And Negative Leptons at BABAR. United States: N. p., 2005. Web. doi:10.2172/878791.
Koptchev, Ventzislav B, & /Massachusetts U., Amherst. Study of the Rare Decay B Mesons Decaying to X Mesons Positive And Negative Leptons at BABAR. United States. https://doi.org/10.2172/878791
Koptchev, Ventzislav B, and /Massachusetts U., Amherst. 2005. "Study of the Rare Decay B Mesons Decaying to X Mesons Positive And Negative Leptons at BABAR". United States. https://doi.org/10.2172/878791. https://www.osti.gov/servlets/purl/878791.
@article{osti_878791,
title = {Study of the Rare Decay B Mesons Decaying to X Mesons Positive And Negative Leptons at BABAR},
author = {Koptchev, Ventzislav B and /Massachusetts U., Amherst},
abstractNote = {Flavor-changing neutral current transitions are forbidden at tree level in the Standard Model and can only occur via higher order diagrams. Since the amplitudes for such loops are dominated by the heaviest known particles, and non-SM effects are expected to contribute at the same order as the SM, such processes are an ideal place to look for new physics. We present a measurement of the inclusive branching fraction for the flavor-changing neutral current process B {yields} X{sub s}{ell}{sup +}{ell}{sup -} with a sample of 81.9 fb{sup -1}, collected with the BABAR detector at the Stanford Linear Accelerator Center. The final state is reconstructed from e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -} pairs and a hadronic system consisting of one K{sup {+-}} or K{sub s} and up to two pions, with at most one {pi}{sup 0}. They observe a signal of 40 {+-} 10(stat) {+-} 2(syst) events and extract a branching fraction {Beta}(B {yields} X{sub s}{ell}{sup +}{ell}{sup -}) = (5.6 {+-} 1.5(stat) {+-} 0.6(exp. syst) {+-} 1.1(model syst)) x 10{sup -6} for m{sub ll} > 0.2 GeV.},
doi = {10.2172/878791},
url = {https://www.osti.gov/biblio/878791}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Aug 30 00:00:00 EDT 2005},
month = {Tue Aug 30 00:00:00 EDT 2005}
}