Abstract
The differential cross-section measurements of inclusive photon production, photon+jet production, diphoton production, and the differential cross-section ratio of Z/γ⁎+jet over γ+jet in proton-proton (pp) collisions based on data recorded by the CMS detector at the LHC are presented. The associated production of a photon and one or more jets in pp collisions represents a direct probe of the hard QCD interaction, is sensitive to gluon densities in the proton and is a major source of background to Standard Model searches. The measured distributions, corrected for efficiencies and unfolded to generator level, are compared with theoretical predictions.
Highlights
The differential cross-section measurements of inclusive photon production, photon+jet production at 8 TeV, the diphoton production at 7 TeV, and the differential cross-section ratio of Z/γ∗+jet over γ+jet at 8 TeV based on data recorded by the CMS [1] detector are presented
This plateau is sensitive to the parton distribution functions composition and it is used in new physics searches to evaluate the irreducible background of invisible decays of the Z-boson
The results of the diphoton differential cross-section measurements are presented in figure 2 [5], the invariant mass of the diphoton system is shown, its transverse momentum and the azimuthal angle between the two photons (Δφγγ)
Summary
The differential cross-section measurements of inclusive photon production, photon+jet production at 8 TeV, the diphoton production at 7 TeV, and the differential cross-section ratio of Z/γ∗+jet over γ+jet at 8 TeV based on data recorded by the CMS [1] detector are presented. The measurement of the photon production crosssection represents a very sensitive test of perturbative quantum chromodynamics (pQCD). Measuring the cross-section ratio differentially in pT of the Z+jet over the γ+jet processes, allows to establish the existence of a plateau, that it is supposed to be reached in the ultrarelativistic range, where pZT mZ [2]. This plateau is sensitive to the parton distribution functions (pdf) composition and it is used in new physics searches to evaluate the irreducible background of invisible decays of the Z-boson. Its large sensitivity to the next-to-leading order (NLO) and next-to-next-to-leading-order (NNLO) contributions makes it an important source of experimental input for the pQCD calculations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
