Measurement of the BXsl+lB \to X_s l^+l^- branching fraction and search for direct CP violation from a sum of exclusive final states

Collaboration
Dec 18, 2013
8 pages
Published in:
  • Phys.Rev.Lett. 112 (2014) 211802
  • Published: May 30, 2014
e-Print:
Report number:
  • BABAR-PUB-13-01,
  • SLAC-PUB-15866
Experiments:

Citations per year

201420172020202320240510152025
Abstract: (APS)

We measure the total branching fraction of the flavor-changing neutral-current process BXs+-, along with partial branching fractions in bins of dilepton and hadronic system (Xs) mass, using a sample of 471×106 ϒ(4S)BB¯ events recorded with the BABAR detector. The admixture of charged and neutral B mesons produced at PEP-II2 are reconstructed by combining a dilepton pair with 10 different Xs final states. Extrapolating from a sum over these exclusive modes, we measure a lepton-flavor-averaged inclusive branching fraction B(BXs+-)=[6.73-0.64+0.70(stat)-0.25+0.34(exp syst)±0.50(model syst)]×10-6 for m+2>0.1GeV2/c4. Restricting our analysis exclusively to final states from which a decaying B meson’s flavor can be inferred, we additionally report measurements of the direct CP asymmetry ACP in bins of dilepton mass; over the full dilepton mass range, we find ACP=0.04±0.11±0.01 for a lepton-flavor-averaged sample.

Note:
  • 34 pages, 25 postscript figures, accepted by PRL
  • 13.20.He
  • 11.30.Er
  • neutral current: flavor changing
  • B: branching ratio: measured
  • dilepton: mass
  • BaBar
  • pi: multiplicity
  • K: final state
  • electron positron: annihilation
  • B: pair production