Forward Jets and Forward-Central Jets at CMS

TL;DR

This paper presents measurements of forward and forward-central jet production cross sections at 7 TeV proton-proton collisions, comparing results with theoretical calculations and event generator predictions to test QCD models.

Contribution

It provides the first detailed measurements of forward and forward-central jet cross sections at the LHC, extending the experimental coverage in pseudo-rapidity and testing various QCD-based models.

Findings

Measured cross sections as functions of jet transverse momentum.

Good agreement with next-to-leading order calculations.

Differences observed between various event generator predictions.

Abstract

We report on cross section measurements for inclusive forward jet production and for the simultaneous production of a forward and a central jet in sqrt{s} = 7 TeV pp-collisions. Data collected in 2010, corresponding to an integrated luminosity of 3.14 pb^{-1}, is used for the measurements. Jets in the transverse momentum range pT = 35 - 140 GeV/c are reconstructed with the anti-kT (R = 0.5) algorithm. The extended coverage of large pseudo-rapidities is provided by the Hadronic Forward calorimeter (3.2 < \eta < 4.7), while central jets are limited to \eta < 2.8, covered by the main detector components. The two differential cross sections are presented as a function of the jet transverse momentum. Comparisons to next-to-leading order perturbative calculations, and predictions from event generators based on different parton showering mechanisms (PYTHIA and HERWIG) and parton dynamics (CASCADE) are shown.