arXiv subjects
Publications and source records attributed to P. Reznicek.
In these mini-proceedings we review the results of the workshop `Impact of $B\toμ^+μ^-$ on New Physics Searches' that took place at the Paul Scherrer Institute (PSI) on the 18th-19th December 2017.
An overview of ATLAS and CMS studies of B_s leptonic decays providing constraints on the lepton flavour violation phenomenon is presented. Except direct lepton flavour violating final states B_s -> l_1^+ l_2^-, constraints can also be set by a measurement of B_s -> mu^+ mu^- decay, whose branching ratio in some theoretical models correlates with a branching ratio of B_s -> l_1^+ l_2^-, tau -> 3mu and some other lepton flavour violating decays. In this paper, the feasibility of measurements of B_s -> mu^+ mu^- decay is described, including the present status, the trigger and the offline analysis strategies and the expected reach in the branching ratio measurement. The ATLAS and CMS experiments foresee to provide 3-sigma evidence of Standard Model B_s -> mu^+ mu^- branching ratio by the end of LHC low-luminosity stage (30 fb^(-1)). Also a CMS study of the tau -> 3mu decay and an initial particle-level based study of the B_s -> tau mu decay are presented. A sensitivity of ~10^(-8) for the tau -> 3mu branching ratio measurement is predicted by CMS.
With the advent of the LHC, we will be able to probe New Physics (NP) up to energy scales almost one order of magnitude larger than it has been possible with present accelerator facilities. While direct detection of new particles will be the main avenue to establish the presence of NP at the LHC, indirect searches will provide precious complementary information, since most probably it will not be possible to measure the full spectrum of new particles and their couplings through direct production. In particular, precision measurements and computations in the realm of flavour physics are expected to play a key role in constraining the unknown parameters of the Lagrangian of any NP model emerging from direct searches at the LHC. The aim of Working Group 2 was twofold: on one hand, to provide a coherent, up-to-date picture of the status of flavour physics before the start of the LHC; on the other hand, to initiate activities on the path towards integrating information on NP from high-pT and flavour data.