Confronting the vector leptoquark hypothesis with new low- and high-energy data

Abstract

In light of new data we present an updated phenomenological analysis of the simplified $U_1$-leptoquark model addressing charged-current $B$-meson anomalies. The analysis shows a good compatibility of low-energy data (dominated by the lepton flavor universality ratios $R_D$ and $R_{D^{\ast }}$) with the high-energy constraints posed by $pp\to \tau \bar{\tau }$ Drell-Yan data. We also show that present data are well compatible with a framework where the leptoquark couples with similar strength to both left- and right-handed third-generation fermions, a scenario that is well-motivated from a model building perspective. We find that the high-energy implications of this setup will be probed at the 95% confidence level in the high-luminosity phase of the LHC.

Comments: 8 pages, 1 appendix, 5 figures. Fixes a bug with the old HFLAV average of RD and RD* & added new RD* data. Expanded appendix, results unchanged