Measurement of the Shape of the Boson-Transverse Momentum Distribution in pp → Z/ γ* = → e⁺e^- + X Events Produced at √s = 1.96 TeV

Authors

V. M. Abazov, Joint Institute for Nuclear Research, Dubna, Russia
Kenneth A. Bloom, University of Nebraska-LincolnFollow
Gregory Snow, University of Nebraska-LincolnFollow
D0 Collaboration

Date of this Version

March 2008

Comments

Published by American Physical Society. Phys. Rev. Lett. 100, 102002 (2008). http://prl.aps.org. Copyright © 2008 American Physical Society. Permission to use.

Abstract

We present a measurement of the shape of the Z/γ* boson transverse momentum (q_T) distribution in pp → Z/γ* → e⁺e^- + X events at a center-of-mass energy of 1.96 TeVusing 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.