标题： 在 HERA 上深非弹性散射中伴随喷注的孤立光子产生进一步研究 显示英文标题

标题： Further studies of isolated photon production with a jet in deep inelastic scattering at HERA

摘要： Isolated photons with high transverse energy have been studied in deep inelastic $ep$ scattering with the ZEUS detector at HERA, using an integrated luminosity of $326\,$ pb$^{-1}$ in the range of exchanged-photon virtuality $10 - 350$ GeV$^2$. 测量了具有横向能量为$4<E_T^\gamma< 15$GeV 和伪快度为$-0.7 <\eta^\gamma< 0.9$的单举孤立光子，并伴随有横向能量和伪快度分别为$2.5 <E_T^{jet}<35$GeV 和$-1.5<\eta^{jet}< 1.8$的喷注。 给出了以下变量的微分横截面：入射光子的能量和动量转移到出射光子和领头喷注的比例；入射质子的能量转移到光子和领头喷注的比例；出射光子与领头喷注之间以及出射光子与散射电子之间的方位角差和伪快度差。 将其与理论预测进行了比较：次领头对数蒙特卡罗模拟、次领头阶 QCD 预测以及使用$k_T$因子化方法的预测。 显示英文摘要

摘要： Isolated photons with high transverse energy have been studied in deep inelastic $ep$ scattering with the ZEUS detector at HERA, using an integrated luminosity of $326\,$ pb$^{-1}$ in the range of exchanged-photon virtuality $10 - 350$ GeV$^2$. Outgoing isolated photons with transverse energy $4<E_T^\gamma< 15$ GeV and pseudorapidity $-0.7 <\eta^\gamma< 0.9$ were measured with accompanying jets having transverse energy and pseudorapidity $2.5 <E_T^{jet}<35$ GeV and $-1.5<\eta^{jet}< 1.8$, respectively. Differential cross sections are presented for the following variables: the fraction of the incoming photon energy and momentum that is transferred to the outgoing photon and the leading jet; the fraction of the incoming proton energy transferred to the photon and leading jet; the differences in azimuthal angle and pseudorapidity between the outgoing photon and the leading jet and between the outgoing photon and the scattered electron. Comparisons are made with theoretical predictions: a leading-logarithm Monte Carlo simulation, a next-to-leading-order QCD prediction, and a prediction using the $k_T$-factorisation approach.