Search for new particles in events with one lepton and missing transverse momentum in $pp$ collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector

TL;DR

This study searches for new particles like $W'$ and $W^{*}$ in proton-proton collisions at 8 TeV using ATLAS data, setting exclusion limits up to around 3.2 TeV, but finds no evidence of new physics.

Contribution

First search for $W'$ and $W^{*}$ particles in events with one lepton and missing momentum at 8 TeV with ATLAS, establishing new exclusion limits.

Findings

Excluded $W'$ masses up to 3.24 TeV

Excluded $W^{*}$ masses up to 3.21 TeV

Set limits on dark matter interaction parameters

Abstract

This paper presents a search for new particles in events with one lepton (electron or muon) and missing transverse momentum using 20.3 $fb^{-1}$ of proton-proton collision data at $\sqrt{s}=8$ TeV recorded by the ATLAS experiment at the Large Hadron Collider. No significant excess beyond Standard Model expectations is observed. A $W'$ with Sequential Standard Model couplings is excluded at the 95% confidence level for masses up to 3.24 TeV. Excited chiral bosons ($W^{*}$) with equivalent coupling strengths are excluded for masses up to 3.21 TeV. In the framework of an effective field theory limits are also set on the dark matter-nucleon scattering cross-section as well as the mass scale $M_{*}$ of the unknown mediating interaction for dark matter pair production in association with a leptonically decaying $W$.