Nonperturbative contributions to a resummed leptonic angular distribution in inclusive $Z/γ^*$ boson production

Abstract

We summarize a new analysis of the distribution $φ_η^{*}$ of charged leptons produced in decays of $Z$ and $γ^{*}$ bosons in the Collins-Soper-Sterman (CSS) formalism for transverse momentum resummation. By comparing the $φ_η^{*}$ distribution measured at the Tevatron with the resummed CSS cross section with approximate ${\cal O}(α_{s}^{2})$ Wilson coefficients, we constrain the magnitude of the nonperturbative Gaussian smearing factor and analyze its uncertainty caused by variations in scale parameters. We find excellent agreement between the $φ_η^{*}$ data and our theoretical prediction, provided by the \textsc{ResBos} resummation program. The nonperturbative factor that we obtained can be used to update resummed QCD predictions for precision measurements in inclusive $W$ and $Z$ production and for comparisons to various models of nonperturbative dynamics.

Figures (2)

• Figure 1: Impact of the scale variation on the agreement between theory and data for $|y_{Z}|\leq1$.
• Figure 2: Estimate of coefficient $a_{1}$ in the three bins of rapidity of the data without (left inset) and with (right inset) $C_{1},C_{2}$ and $C_{3}$ shifts.