Measurements of inclusive W+jets production rates as a function of jet transverse momentum in ppbar collisions at sqrt{s}=1.96 TeV

Abstract

This Letter describes measurements of inclusive W (--> e nu) + n jet cross sections (n = 1-4), presented as total inclusive cross sections and differentially in the nth jet transverse momentum. The measurements are made using data corresponding to an integrated luminosity of 4.2 fb-1 collected by the D0 detector at the Fermilab Tevatron Collider, and achieve considerably smaller uncertainties on W +jets production cross sections than previous measurements. The measurements are compared to next-to-leading order perturbative QCD (pQCD) calculations in the n =1-3 jet multiplicity bins and to leading order pQCD calculations in the 4-jet bin. The measurements are generally in agreement with pQCD predictions, although certain regions of phase space are identified where the calculations could be improved.

Figures (3)

• Figure 1: (a) Total inclusive $n$-jet cross sections $\sigma_n=\sigma (W(\rightarrow e\nu)\ + \geq \space n\text{ jet;}\; p^{\text{jet}}_T>20~\textrm{GeV})$ as a function of inclusive jet multiplicity, (b) the ratio of the theory predictions to the measurements, and (c) $\sigma_n/\sigma_{n-1}$ ratios for data, blackhat+sherpa and rocket+mcfm. Error bars on data points represent combined statistical and systematic uncertainties on measured cross sections. The uncertainties on the theory points in (a) and (c) and the hashed areas in (b) represent the theoretical uncertainty arising from the choice of renormalization and factorization scale. In (b) the error bars on the points represent the data uncertainties.
• Figure 2: Measured $W$+n jet differential cross section as a function of $n^{\text{th}}$ jet $p_T$ for jet multiplicities $n=$1--4, normalized to the inclusive $W \rightarrow e \nu$ cross section. $W$+1 jet inclusive spectra are shown by the top curve, the $W$+4 jet inclusive spectra by the bottom curve. The measurements are compared to the fixed-order NLO predictions for the jet multiplicities $n=$1--3, and to LO predictions for $n=4$.
• Figure 3: The ratio of pQCD predictions to the measured differential cross sections for the $n^{\text{th}}$ jet $p_T$ in (a) $W$+1 jet events, (b) $W$+2 jet events, (c) $W$+3 jet events, and (d) $W$+4 jet events. The inner (red) bars represent the statistical uncertainties of the measurement, while the outer (black) bars represent the statistical and systematic uncertainties added in quadrature. The shaded areas indicate the theoretical uncertainties due to variations of the factorization and renormalization scale.