Search for a new neutral gauge boson produced in association with one or two b jets and decaying into a pair of muons in proton-proton collisions at $\sqrt{s}$ = 13 TeV

TL;DR

This paper reports a search for a new neutral gauge boson Z' produced with b jets and decaying into muon pairs, setting upper limits on its production cross section in the 125-350 GeV mass range using CMS data.

Contribution

It provides the first results in the 125-200 GeV range and the most stringent limits for b quark fusion production modes in the 200-350 GeV range.

Findings

No significant excess observed over background.

Upper limits on Z' production cross section set between 0.2 and 2 fb.

Results are the most stringent for certain production modes in the studied mass range.

Abstract

A search for a new neutral gauge boson, Z', produced in association with one or two jets, including at least one b jet, and decaying into a pair of muons is presented. The analysis uses proton-proton collision data collected with the CMS detector at $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. No significant deviation from background expectations is observed. Upper limits at 95% confidence level on the product of cross section, branching fraction to dimuons, acceptance, and efficiency, from 0.2 to 2 fb, are set for Z' boson masses between 125 and 350 GeV. Process-dependent products of acceptance and efficiency, and model-independent limits on the signal yield are provided. These are the only results to date in the 125$-$200 GeV mass range and the most stringent for b quark fusion production modes in the 200$-$350 GeV range, complementing inclusive Z' boson searches.