Improved Search for a Higgs Boson Produced in Association with Z->l+l- in proton antiproton Collisions at sqrt(s) = 1.96 TeV

TL;DR

This paper reports a search for the Higgs boson produced with a Z boson in proton-antiproton collisions, setting upper limits on production cross section and improving analysis sensitivity over previous efforts.

Contribution

The study introduces improved analysis methods that increase signal sensitivity by 20%, leading to more stringent limits on Higgs production at the Tevatron.

Findings

Set a 95% credibility level upper limit of 5.9 times the SM prediction at 115 GeV/c^2

Enhanced analysis techniques improved sensitivity by 20%

Provided the most stringent limits for ZH production in this channel to date.

Abstract

We present a search for the standard model Higgs boson produced with a Z boson in 4.1 fb^-1 of data collected with the CDF II detector at the Tevatron. In events consistent with the decay of the Higgs boson to a bottom-quark pair and the Z boson to electrons or muons, we set 95% credibility level upper limits on the ZH production cross section times the H -> b bbar branching ratio. Improved analysis methods enhance signal sensitivity by 20% relative to previous searches beyond the gain due to the larger data sample. At a Higgs boson mass of 115 GeV/c^2 we set a limit of 5.9 times the standard model value.