Measurement of the differential photon+ c-jet cross section and the ratio of differential photon+ c and photon+ b cross sections in proton-antiproton collisions at sqrt(s) = 1.96 TeV

TL;DR

This paper measures the differential cross section of photon plus charm-jet production and compares the ratio of photon+c to photon+b cross sections in proton-antiproton collisions at 1.96 TeV, testing QCD predictions.

Contribution

It provides the first detailed measurement of the photon+c-jet differential cross section and the ratio of photon+c to photon+b cross sections at Tevatron energies, comparing with multiple theoretical models.

Findings

Measured differential cross sections over a wide pT range.

Observed ratios of photon+c to photon+b cross sections.

Results show agreement and discrepancies with QCD models.

Abstract

We present measurements of the differential cross section $d\sigma/dp_{T}^{\gamma}$ for the associated production of a $c$-quark jet and an isolated photon with rapidity $|y^{\gamma}|< 1.0$ and transverse momentum $30 < p_{T}^{\gamma} < 300$ GeV. The $c$-quark jets are required to have $|y^{jet}| < 1.5$ and $p_{T}^{jet} >15$ GeV. The ratio of differential cross sections for photon+ c and photon+ b production as a function of $p_{T}^{\gamma}$ is also presented. The results are based on data corresponding to an integrated luminosity of 8.7 fb$^{-1}$ recorded with the D0 detector at the Fermilab Tevatron $p\bar{p}$ Collider at $\sqrt{s}=$1.96 TeV. The obtained results are compared to next-to-leading order perturbative QCD calculations using various parton distribution functions, to predictions based on the $k_{T}$-factorization approach, and to predictions from the Sherpa and Pythia Monte Carlo event generators.