Differential cross section measurements for the production of a W boson in association with jets in proton-proton collisions at root s=7 TeV

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta ( (p_T) ) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta ( HT ), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb⁻¹. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the (p_T) distributions of the leading jets at high (p_T) values, the distributions of the HT at high- HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.