Measurement of Zγ production in pp̅ collisions at √s=1.96 TeV

Abstract

The production rate and kinematics of photons produced in association with Z bosons are studied using 2 fb-1 of pp̅ collision data collected at the Collider Detector at Fermilab. The cross section for pp̅ →ℓ+ℓ-γ+X (where the leptons ℓ are either muons or electrons with dilepton mass Mℓℓ>40 GeV/c2, and where the photon has transverse energy ETγ>7 GeV and is well separated from the leptons) is 4.6±0.2(stat)±0.3(syst)±0.3(lum) pb, which is consistent with standard model expectations. We use the photon ET distribution from Zγ events where the Z has decayed to μ+μ-, e+e-, or νν̅ to set limits on anomalous (non standard model) trilinear couplings between photons and Z bosons.