We find evidence for the semileptonic baryonic decay B-?pp¯l-?¯l (l=e, µ), based on a data sample of 772 million BB¯ pairs collected at the ?(4S) resonance with the Belle detector at the KEKB asymmetric-energy electron-positron collider. A neural-network based hadronic B-meson tagging method is used in this study. The branching fraction of B-?pp¯l-?¯l is measured to be (5.8+2.4-2.1(stat)±0.9(syst))×10-6 with a significance of 3.2s, where lepton universality is assumed. We also estimate the corresponding upper limit: B(B-?pp¯l-?¯l)
Revised: August 12, 2014 |
Published: January 9, 2014
Citation
Tien K., M.Z. Wang, I. Adachi, H. Aihara, D.M. Asner, V. Aulchenko, and T. Aushev, et al. 2014.Evidence for Semileptonic B-?pp¯l-?¯l Decays.Physical Review D 89, no. 1:Article No. 011101.PNNL-SA-99792.doi:10.1103/PhysRevD.89.011101