Measurement of Z_gamma Production in p anti-p Collisions at s**(1/2) 1.96 TeV

The production rate and kinematics of photons produced in association with Z bosons are studied using 2 fb-1 of p anti-p collision data collected at the Collider Detector at Fermilab. The cross section for p anti-p -> ell+ ell- gamma + X (where the leptons ell are either muons or electrons with dilepton mass M_ell ell > 40 GeV/c2, and where the photon has transverse energy Egamma_T > 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 E(t) distribution from Z_gamma events where the Z has decayed to mu+ mu-, e+ e-, or nu nu-bar to set limits on anomalous (non-standard-model) trilinear couplings between photons and Z bosons.