Unraveling the couplings of a Drell-Yan produced $Z^{\prime }$ with heavy-flavor tagging

Abstract

Despite no new physics so far at the LHC, a $Z^{\prime }$ boson with $m_{Z^{\prime }}\sim 100$ GeV could still emerge via Drell-Yan (DY) production, $q\bar{q}\to Z^{\prime }\to {\mu }^{+}{\mu }^{-}$, in the next few years. To unravel the nature of the $Z^{\prime }$ coupling, we utilize the $c$- and $b$-tagging algorithms developed by ATLAS and CMS to investigate $cg\to c{Z}^{\prime }$ at 14 TeV LHC. While light-jet contamination can be eliminated, mistagged $b$-jets cannot be rejected in any of the tagging schemes we adopt. On the other hand, for nonzero $bb{Z}^{\prime }$ coupling, far superior $b$-tagging could discover the $bg\to b{Z}^{\prime }$ process, where again light-jet mistag can be ruled out, but mistagged $c$-jets cannot yet be excluded. Provided that DY production is discovered soon enough, we find that a simultaneous search for $cg\to c{Z}^{\prime }$ and $bg\to b{Z}^{\prime }$ can conclusively discern the nature of $Z^{\prime }$ couplings involved.

Comments: matches with published version