Direct CP, Lepton Flavor, and Isospin Asymmetries in the Decays B -> K((*))l( )l(-)

作者：Aubert B^*; Bona M; Karyotakis Y; Lees J P; Poireau V; Prencipe E; Prudent X; Tisserand V; Tico J Garra; Grauges E; Lopez L; Palano A; Pappagallo M; Eigen G; Stugu B; Sun L; Abrams G S; Battaglia M; Brown D N; Cahn R N; Jacobsen R G; Kerth L T; Kolomensky Yu G; Lynch G; Osipenkov I L; Ronan M T; Tackmann K; Tanabe T; Hawkes C M; Soni N; Watson A T; Koch H; Schroeder T; Walker D; Asgeirsson D J; Fulsom B G

来源：Physical Review Letters, 2009, 102(9): 091803.

DOI：10.1103/PhysRevLett.102.091803

We measure branching fractions and integrated rate asymmetries for the rare decays B -> K((*))l( )l(-), where l( )l(-) is either e( )e(-) or mu( )mu(-), using a sample of 384x10(6) BB events collected with the BABAR detector at the PEP-II e( )e(-) collider. We find no evidence for direct CP or lepton-flavor asymmetries. However, for dilepton masses below the J/psi resonance, we find evidence for unexpectedly large isospin asymmetries in both B -> Kl( )l(-) and B -> K(*)l( )l(-) which differ, respectively, by 3.2 sigma and 2.7 sigma, including systematic uncertainties, from the standard model expectations.

• 出版日期2009-3-6
• 单位McGill; Perugia; 中国地震局; 中国科学院高能物理研究所