Precision Top Quark Mass Measurement in the Lepton + Jets Topology in ppbar Collisions at sqrt(s) = 1.96 TeV

TL;DR

This paper presents two measurements of the top quark mass in proton-antiproton collisions using the CDF II detector, employing likelihood and invariant mass reconstruction methods, resulting in a precise combined value.

Contribution

The paper introduces two novel measurement techniques for the top quark mass in the lepton + jets channel at the Tevatron, improving precision over previous methods.

Findings

Top quark mass measured as 173.2 +4.1/-4.0 GeV/c^2

Alternative method yields 173.5 +3.9/-3.8 GeV/c^2

Combined result enhances top quark mass precision

Abstract

We report two measurements of the top quark mass M_top using the CDF II detector at the Fermilab Tevatron in a 318 pb^-1 data sample observed in the lepton + jets final state. One method uses an event-based likelihood technique resulting in M_top = 173.2 +2.6/-2.4 (stat.) +/- 3.2 (syst.) GeV/c^2 or 173.2 +4.1/-4.0 GeV/c^2. The second method reconstructs a top quark mass in each event using the measured invariant mass of the hadronically decaying W boson to constrain the jet energy scale to obtain a value for M_top of 173.5 +3.7/-3.6 (stat.) +/- 1.3 (syst.) GeV/c^2 or 173.5 +3.9/-3.8 GeV/c^2. We take the latter, which is more precise, as our result.