Measurement of sin(2)theta(l)(eff) and Z-light quark couplings using the forward-backward charge asymmetry in p(p)over-bar -} Z/gamma* -} e(+)e(-) events with L=5.0 fb(-1) at sqrt(s)=1.96 TeV
2011
Abstract
We measure the mass dependence of the forward-backward charge asymmetry in 157 553 p (p) over bar -} Z/gamma* -} e(+)e(-) interactions, corresponding to 5.0 fb(-1) of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron Collider at root s = 1.96 TeV. The effective weak mixing angle (theta(l)(eff)) from this process involving predominantly the first generation of quarks is extracted as sin(2)theta(l)(eff) = 0.2309 +/- 0.0008(stat.) +/- 0: 0006(syst.).
We also present the most precise direct measurement of the vector and axial-vector couplings of u and d quarks to the Z boson.