2012/12/31 by Y. G. Aditya, K. J. Healey, Kristopher J. Healey +1 · 1 citation
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevd.87.074028
published as Phys.Rev. D87 (2013) 074028 · 14 pages, 7 figures, .v2 changes : fixed diagram TeX, small notation change, fixed reference
arxiv created 2013/01/10 · openalex publication_date 2013/04/23 · arxiv updated 2013/05/03 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Recent evidence from observation of the flavor-changing neutral current decay Bs0\ensuremath→\ensuremathμ+\ensuremathμ^\ensuremath- by the LHCb Collaboration B(Bs0\ensuremath→\ensuremathμ+\ensuremathμ^\ensuremath-)=(3.2_\ensuremath-1.2+1.5)\ifmmode×\else\texttimes\fi10^\ensuremath-9 is consistent with the latest standard model prediction BSM(Bs0\ensuremath→\ensuremathμ+\ensuremathμ^\ensuremath-)=(3.23\ifmmode±\else\textpm\fi0.27)\ifmmode×\else\texttimes\fi10^\ensuremath-9. While new physics can still affect this decay amplitude, its contribution is certainly not the dominant one. We analyze branching ratios of the decays Bs0\ensuremath→\ensuremathμ+\ensuremathμ^\ensuremath-X, with X=\ensuremathγ or \ensuremathν\ensuremathν, which can mimic Bs0\ensuremath→\ensuremathμ+\ensuremathμ^\ensuremath- on portions of the parameter space where X is soft. Since detection efficiency of \ensuremathγ or \ensuremathν\ensuremathν in modern charm-physics experiments is quite low in that region, those processes could be misidentified as Bs0\ensuremath→\ensuremathμ+\ensuremathμ^\ensuremath-. We perform a model-independent standard model calculation of those processes incorporating heavy quark and chiral symmetries of QCD concentrating on the soft-X region. We show that misidentification of the considered processes can only boost the Bs0\ensuremath→\ensuremathμ+\ensuremathμ^\ensuremath- rate by less than a percent.