Study Of Dijet Events With A Large Rapidity Gap Between The Two Leading Jets İn Pp Collisions At Root S = 7tev

Abstract

tEventswithnochargedparticlesproducedbetween the two leading jets are studied in proton–proton collisions at ?s = 7TeV. The jets were required to have transverse momentum pjet T > 40GeVandpseudorapidity1.5 < |?jet| <4 .7, and to have values of ?jet with opposite signs. The data usedforthisstudywerecollectedwiththeCMSdetectorduring low-luminosity running at the LHC, and correspond to an integrated luminosity of 8pb?1. Events with no charged particles with pT > 0.2GeV in the interval ?1 <?<1 between the jets are observed in excess of calculations that assume no color-singlet exchange. The fraction of events withsucharapiditygap,amountingto0.5–1%oftheselected dijet sample, is measured as a function of the pT of the The original article can be found online at https://doi.org/10.1140/ epjc/s10052-018-5691-6. We dedicate this paper to the memory of our colleague and friend Sasha Proskuryakov, who started this analysis but passed away before it was completed. His contribution to the study of diffractive processes at CMS is invaluable. e-mail: cms-publication-committee-chair@cern.ch second-leading jet and of the rapidity separation between the jets. The data are compared to previous measurements at the Tevatron, and to perturbative quantum chromodynamics calculations based on the Balitsky–Fadin–Kuraev–Lipatov evolution equations, including different models of the nonperturbative gap survival probability