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تسجيل مستخدم جديدQuark Excitations Through the Prism of Direct Photon Plus Jet at the LHC
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The quest to know the structure of matter has resulted in various theoretical speculations wherein additional colored fermions are postulated. Arising either as Kaluza-Klein excitations of ordinary quarks, or as excited states in scenarios wherein the quarks themselves are composites, or even in theories with extended gauge symmetry, the presence of such fermions ($q^*$) can potentially be manifested in $gamma + jet$ final states at the LHC. Using unitarized amplitudes and the CMS setup, we demonstrate that in the initial phase of LHC operation (with an integrated luminosity of $200 pb^{-1}$) one can discover such states for a mass upto 2.0 TeV. The discovery of a $q^*$ with a mass as large as $sim$5 TeV can be acheived for an integrated luminosity of $sim 140 fb^{-1}$. We also comment on the feasibility of mass determination.
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