First Measurement of the Angular Coefficients of Drell-Yan e~+e~- Pairs in the Z Mass Region from pp Collisions at s~(1/s) - 1.96 TeV

摘要

We report on the first measurement of the angular distributions of final state electrons in pp → γ~*/Z → e~+e~- + X events produced in the Z boson mass region at s~(1/s) = 1.96 TeV. The data sample collected by the CDF II detector for this result corresponds to 2.1 fb"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.