T-odd Asymmetry in W+jet Events at the LHC

Abstract

W bosons produced at high transverse momentum in hadron collisions can have polarization along the direction perpendicular to the production plane, which is odd under na$\ddot{ı}$ve-T-reversal where both the three-momenta and angular momenta are reversed. Perturbative QCD predicts non-zero polarization at the one-loop level, which can be measured as parity-odd components in the angular distribution of charged leptons from the decay of W bosons. We perform a detector-level simulation with the generator MadGraph5_aMC@NLO, and demonstrate that the asymmetry can be observed at the 8 TeV LHC with 20 fb${}^{-1}$ of data. If confirmed, it will be the first experimental measurement of the sign of the imaginary part of one-loop QCD amplitudes.

5 pages, 2 figures

References in corpus (4)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Reducing full one-loop amplitudes to scalar integrals at the integrand level
• Automation of next-to-leading order computations in QCD: the FKS subtraction
• Parity-Odd Asymmetries in W-Jet Events at the Tevatron

Cited by in corpus (5)

• Machine-enhanced CP-asymmetries in the Higgs sector
• W production at LHC: lepton angular distributions and reference frames for probing hard QCD
• Perturbative $T$-odd asymmetries in the Drell-Yan process revisited
• CP violating anomalous couplings in $W$ jet production at the LHC
• T-odd proton-helicity asymmetry in semi-inclusive DIS in perturbative QCD