Search for High Mass Resonances Decaying to Muon Pairs in $\sqrt{s}=1.96$ TeV $p\bar{p}$ Collisions

TL;DR

This study searches for high mass spin-1 resonances decaying to muon pairs in proton-antiproton collisions at 1.96 TeV, using a likelihood approach, but finds no evidence and sets mass limits on potential new particles.

Contribution

It introduces a matrix element based likelihood method to search for narrow high mass resonances decaying to muons in collider data.

Findings

No significant signal observed at 16% confidence level.

Limits set on $Z'$ boson mass, exceeding 1071 GeV/$c^2$ at 95% CL.

Abstract

We present a search for a new narrow, spin-1, high mass resonance decaying to $\mu^+\mu^- + X $, using a matrix element based likelihood and a simultaneous measurement of the resonance mass and production rate. In data with 4.6 fb$^{-1}$ of integrated luminosity collected by the CDF detector in $p\bar{p}$ collisions at $\sqrt{s}=1960$ GeV, the most likely signal cross section is consistent with zero at 16\% confidence level. We therefore do not observe evidence for a high mass resonance, and place limits on models predicting spin-1 resonances, including $M > 1071$ GeV/$c^2$ at 95\% confidence level for a $Z'$ boson with the same couplings to fermions as the $Z$ boson.