CamargoMolina, Jose Eliel; Cells, Alejandro; Faroughy, Darius A.
(2018):
Anomalies in bottom from new physics in top.
In: Physics Letters B, Vol. 784: pp. 284293

Abstract
We analyze the possibility to accommodate current b > sl(+)l() anomalies with TeVscale mediators that couple to righthanded top quarks and muons, contributing to b > sl(+)l() at the oneloop level. We use the Standard Model Effective Field Theory (SMEFT) framework but also look at specific scenarios by taking into account all possible irreducible representations of the Lorentz and Standard Model gauge group for the mediators. From a global fit of b > sl(+)l() data and LEPI observables we find that the Wilson coefficients of two SMEFT operators: Olu, = ((l) over bar (L mu)gamma(alpha)l(L mu))((t) over bar (R)gamma(alpha)t(R)) and Oeu = ((mu) over bar (R)gamma(alpha)mu(R))((t) over bar (R)gamma(alpha)t(R)) need to satisfy Ceu similar to Clu. New physics enters then in b > sl(+)l() mainly through the operator O9 = ((S) over bar)gamma(mu)P(L)b)((l) over bar gamma(mu)l) of the Weak Effective Theory. After discussing all possible mediators, we concentrate on two scenarios: A vector boson in the irreducible representation Z'(mu) similar to (1,1,0) of the Standard Model gauge group with vectorial coupling to muons, and a combination of two leptoquarks: the scalar R2 similar to (3,2,7/6) and the vector (U) over tilde (1 mu) similar to (3,1,5/3). We derive LHC constraints by recasting dimuon resonance, pp > t (t) over bart (t) over bar and SUSY searches. Additionally, we analyze the prospects for discovering these mediators during the high luminosity phase of the LHC.