Measurement of the shape of the Boson-transverse momentum distribution in pp̅→Z/γ→ e⁺e^-+X events produced at √s=1.96 TeV

Abstract

We present a measurement of the shape of the Z/γboson transverse momentum (q_T) distribution in pp̅→Z/γe⁺e^-+X events at a center-of-mass energy of 1.96 TeV using 0.98 fb^-1 of data collected with the D0 detector at the Fermilab Tevatron collider. The data are found to be consistent with the resummation prediction at low q_T, but above the perturbative QCD calculation in the region of q_T>30 GeV/c. Using events with q_T>30 GeV/c, we extract the value of g₂, one of the nonperturbative parameters for the resummation calculation. Data at large boson rapidity y are compared with the prediction of resummation and with alternative models that employ a resummed form factor with modifications in the small Bjorken x region of the proton wave function.