CMS-FWD-11-003 ; CERN-PH-EP-2013-012 | ||
Study of the underlying event at forward rapidity in pp collisions at $\sqrt{s}$ = 0.9, 2.76, and 7 TeV | ||
CMS Collaboration | ||
11 February 2013 | ||
J. High Energy Phys. 04 (2013) 072 | ||
Abstract: The underlying event activity in proton-proton collisions at forward pseudorapidity (-6.6 $\lt \eta \lt$ -5.2) is studied with the CMS detector at the LHC, using a novel observable: the ratio of the forward energy density, dE/d$\eta$, for events with a charged-particle jet produced at central pseudorapidity (abs(eta[jet]) $\lt$ 2) to the forward energy density for inclusive events. This forward energy density ratio is measured as a function of the central jet transverse momentum, pt, at three different pp centre-of-mass energies ($\sqrt{s}$ = 0.9, 2.76, and 7 TeV). In addition, the $\sqrt{s}$ 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 underlying event. Whereas the dependence of the forward energy density ratio on jet pt at each $\sqrt{s}$ separately can be well reproduced by some models, all models fail to simultaneously describe the increase of the forward energy density with $\sqrt{s}$ in both inclusive events and in events with a central jet. | ||
Links: e-print arXiv:1302.2394 [hep-ex] (PDF) ; CDS record ; inSPIRE record ; Public twiki page ; HepData record ; CADI line (restricted) ; |
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Compact Muon Solenoid LHC, CERN |