Charm tagging and the H -> W^+W^- -> l nu c j semi-leptonic channel

TL;DR

This paper proposes a novel method for Higgs boson discovery at the LHC using charm jet tagging in the semi-leptonic W decay channel, which could enhance detection sensitivity and provide complementary insights to existing methods.

Contribution

It introduces a new charm jet tagging approach and explores its potential for Higgs discovery via the H -> W^+W^- -> l nu c j channel, offering a complementary detection strategy.

Findings

A 50% charm tagging efficiency could enable a 5-sigma Higgs discovery with 7 fb^-1 at 14 TeV.

Charm tagging sensitivity is comparable to WW fusion in standard model Higgs detection.

The method can potentially exclude Higgs bosons at a 7 TeV collider.

Abstract

We introduce a method to discover the Higgs boson at the Large Hadron Collider (LHC) through its decay to W^+W^-, where one boson decays to leptons, and the other decays to c+jet. This mechanism is complementary to the decay into dileptons, but has the potential to measure the invariant mass peak of the Higgs boson, and to avoid large recently discovered QCD backgrounds from heavy flavor decays. In addition, this mechanism motivates the study and creation of a dedicated charm jet tagger at LHC experiments. Existing charm jet tagging, in the form of fakes to bottom jet tagging, provides sensitivity to a standard model Higgs boson that is comparable to WW fusion. A 50% charm tagging efficiency in the relevant kinematic range could allow an independent 5-sigma discovery of a 165 GeV Higgs boson in 7 fb^-1 of integrated luminosity at a 14 TeV machine, or exclusion with a 7 TeV collider.