F. Abe et al., Measurement of the lepton charge asymmetry in W-boson decays produced in p(p)over-bar collisions, PHYS REV L, 81(26), 1998, pp. 5754-5759
We describe a measurement of the charge asymmetry of leptons from W-boson d
ecays in the rapidity range 0 less-than [y(iota)] < 2.5 using W --> e nu, m
u nu events from 110 +/- 7 pb(-1) of data collected by the CDF detector dur
ing 1992-1995. The asymmetry data constrain the ratio of d and u quark mome
ntum distributions in the proton over the x range of 0.006 to 0.34 at Q(2)
= M-W(2). The asymmetry predictions that use parton distribution functions
obtained from previously published CDF data in the central rapidity region
(0.0 less-than [y(iota)] less-than 1.1) do not agree with the new data in t
he large rapidity region ([y(iota)] greater-than 1.1).