Backgrounds To Higgs Boson Searches from Asymmetric Internal Conversion

Abstract

A class of potential backgrounds for Higgs boson searches in the W W to di-lepton channel at both the Tevatron and Large Hadron Collider is presented. Backgrounds from W photon production with external conversion of the on-shell photon in detector material to an asymmetric electron-positron pair, with loss of the trailing electron or positron has been treated adequately in Higgs searches. Here we consider analogous backgrounds from the production of a W with an off-shell photon and with the internal conversion of the off-shell photon in vacuum to an asymmetric lepton-anti-lepton pair. While the former process yields almost entirely electrons or positrons, the latter can give electron, positron, muon, and anti-muon backgrounds in roughly equal amounts. We estimate that asymmetric internal conversion backgrounds are comparable to the Higgs boson signal in the standard signal region of phase space. These processes also represent potential backgrounds for new physics searches in same-sign di-lepton channels. Some data driven methods to characterize asymmetric internal conversion backgrounds are suggested.

16 pages, 5 figures

References in corpus (3)

• Measurement of WW Production and Search for the Higgs Boson in pp Collisions at sqrt(s) = 7 TeV
• Limits on the production of the Standard Model Higgs Boson in pp collisions at sqrt(s) =7 TeV with the ATLAS detector
• Inclusive Search for Standard Model Higgs Boson Production in the WW Decay Channel using the CDF II Detector

Cited by in corpus (10)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC
• Measurement of Higgs boson production and properties in the WW decay channel with leptonic final states
• Measurement of W+W- and ZZ production cross sections in pp collisions at sqrt(s) = 8 TeV
• Search for the standard model Higgs boson decaying to a W pair in the fully leptonic final state in pp collisions at sqrt(s) = 7 TeV
• Measurement of the W+W- cross section in pp collisions at sqrt(s) = 7 TeV and limits on anomalous WW gamma and WWZ couplings
• Measurement of the W+ W- cross section in pp collisions at sqrt(s) = 8 TeV and limits on anomalous gauge couplings
• Search for the Standard Model Higgs boson in the H -> WW(*) -> l nu l nu decay mode with 4.7 /fb of ATLAS data at sqrt(s) = 7 TeV
• Searching for $t\to ch$ with Multi-Leptons
• Multi-Lepton Signals of Top-Higgs Associated Production