First measurement of the angular coefficients of drell-yan e +e- Pairs in the Z mass region from pp̄ collisions at √s=1.96TeV

Abstract

We report on the first measurement of the angular distributions of final state electrons in pp̄→γ*/Z→e +e-+X events produced in the Z boson mass region at √s=1.96TeV. The data sample collected by the CDF II detector for this result corresponds to 2.1fb-1 of integrated luminosity. The angular distributions are studied as a function of the transverse momentum of the electron-positron pair and show good agreement with the Lam-Tung relation, consistent with a spin-1 description of the gluon, and demonstrate that, at high values of the transverse momentum, Z bosons are produced via quark-antiquark annihilation and quark-gluon Compton processes. © 2011 American Physical Society.