$P_5^{\prime }$ Anomaly for Top: $t{Z}^{\prime }$ Production at LHC

Abstract

The $P_5^{\prime }$ anomaly uncovered by the LHCb experiment in $B\to K^{\ast }\mu \mu$ angular observables has motivated a possible $Z^{\prime }$ boson that couples to left-handed $b\to s$ transitions, where a model would be gauged $L_{\mu }-L_{\tau }$ symmetry, but direct search for such a $Z^{\prime }$ is not promising. Less constrained is an analogous $Z^{\prime }$ coupling to right-handed $t\to c$ transitions. Motivated by this, we study $cg\to t{Z}^{\prime }$ associated production at LHC, both for a generic model, and in $L_{\mu }-L_{\tau }$ with a vector-like U quark. We also study $c\bar{c}\to Z^{\prime }$ production that exists within the model. Both processes can be probed already with LHC Run 2 data, all the way up to the HL-LHC with discovery potential.

Comments: 6 pages, 8 figures. Talk presented at the APS Division of Particles and Fields Meeting (DPF 2017), July 31-August 4, 2017, Fermilab. C170731