Document Type
Article
Publication Title
Journal of High Energy Physics
Abstract
The underlying event activity in proton-proton collisions at forward pseudo- rapidity (−6.6 < η < −5.2) is studied with the CMS detector at the LHC, using a novel observable: the ratio of the forward energy density, dE/dη, for events with a charged- particle jet produced at central pseudorapidity (|ηjet| < 2) to the forward energy density for inclusive events. This forward energy density ratio is measured as a function of the cen- tral jet transverse momentum, pT, at three different pp centre-of-mass energies (√s = 0.9, 2.76, and 7 TeV). In addition, the √s evolution of the forward energy density is studied in inclusive events and in events with a central jet. The results are compared to those of Monte Carlo event generators for pp collisions and are discussed in terms of the underly- ing event. Whereas the dependence of the forward energy density ratio on jet pT at each √s separately can be well reproduced by some models, all models fail to simultaneously describe the increase of the forward energy density with √s in both inclusive events and in events with a central jet.
DOI
10.1007/JHEP04(2013)072
Publication Date
4-2013
Recommended Citation
The CMS Collaboration; Baarmand, M. M.; Dorney, B.; Hohlmann, M.; Kalakhety, H.; Vodopianov, I.; and Yumiceva, F., "Study of the underlying event at forward rapidity in pp collisions at √ s= 7 TeV" (2013). Aerospace, Physics, and Space Science Faculty Publications. 646.
https://repository.fit.edu/apss_faculty/646
