Measurement of the mass of the top quark in decays with a J/psi meson in pp collisions at 8 TeV

TL;DR

This paper reports the first measurement of the top quark mass using a decay channel involving a J/psi meson, based on proton-proton collision data at 8 TeV collected by CMS, resulting in a top mass estimate of 173.5 GeV.

Contribution

It introduces a novel method for measuring the top quark mass using the J/psi decay channel in proton-proton collisions at 8 TeV.

Findings

Measured top quark mass as 173.5 GeV

Used decay channel involving J/psi meson

Achieved statistical and systematic uncertainties

Abstract

A first measurement of the top quark mass using the decay channel t to (W to l nu) (b to J/psi + X to mu+ mu- + X) is presented. The analysis uses events selected from the proton-proton collisions recorded with the CMS detector at the LHC at a center-of-mass energy of 8 TeV. The data correspond to an integrated luminosity of 19.7 inverse femtobarns, with 666 t t-bar and single top quark candidate events containing a reconstructed J/psi candidate decaying into an oppositely-charged muon pair. The mass of the (J/psi + l) system, where l is an electron or a muon from W boson decay, is used to extract a top quark mass of 173.5 +/- 3.0 (stat) +/- 0.9 (syst) GeV.