Comparison of Dijet Cross Sections vs Q^2 with Various Monte Carlo Models

TL;DR

This paper compares dijet cross sections across different photon virtualities with Monte Carlo models, revealing that photon parton distribution functions decrease as photon virtuality increases, consistent with theoretical expectations.

Contribution

It provides a detailed comparison of dijet cross sections with various photon parton distribution functions using Herwig 5.9, highlighting the dependence on photon virtuality.

Findings

The ratio of dijet cross sections decreases with increasing Q^2.

Photon parton distribution functions diminish as photon virtuality increases.

Results support the hypothesis about photon structure functions' behavior.

Abstract

The dijet cross section as a function of both the fraction of the photon momentum participating in the hard process, x_\gamma^{OBS}, and the photon's virtuality, Q^2, is compared with the predictions of Herwig 5.9 for various photon parton distribution functions. The ratio of dijet cross sections with x_\gamma^{OBS} < 0.75 and x_\gamma^{OBS} > 0.75 is measured as a function of Q^2. This ratio is found to decrease as Q^2 increases consistent with the hypothesis that the photon parton distribution functions decrease with increasing photon virtuality.