We study a large-$p_T$ three-photon production in the proton-proton collisions at the LHC. We use the leading order (LO) approximation of the parton Reggeization approach consistently merged with the next-to-leading order corrections originating from the emission of the additional jet. For numerical calculations, we apply the parton-level generator KaTie and the modified Kimder-Martin-Ryskin-type unintegrated parton distribution functions, which satisfy the exact normalization conditions for arbitrary $x$. We compare our prediction with data from the ATLAS collaboration at the center-of-mass energy $\sqrt{s}=8\mathrm{TeV}$. We find that the inclusion of the real next-to-leading-order corrections leads to a good agreement between our predictions and data with the same accuracy as for the next-to-next-to-leading calculations based on the collinear parton model of QCD. At higher energies ($\sqrt{s}=13$ and 27 TeV) the parton Reggeization approach predicts larger cross sections, up to $\sim 15\%$ and $\sim 30\%$, respectively.

中文翻译：

---

在高能下以部分正格化方法产生三个孤立的光子

我们研究了一个大$p_{吨}$大型强子对撞机质子-质子碰撞中的三光子产生。我们使用部分正则化方法的前导阶 (LO) 近似值，始终与源自额外射流排放的次导阶校正合并。对于数值计算，我们应用部分子级生成器 KaTie 和改进的 Kimder-Martin-Ryskin 型未积分部分子分布函数，它们满足任意$X$. 我们将我们的预测与质心能量的 ATLAS 合作数据进行比较$\sqrt{s}=8\mathrm{TeV}$. 我们发现，包含真正的下一个领先订单校正导致我们的预测与数据之间具有良好的一致性，其准确性与基于共线部分模型的下一个领先计算的准确性相同QCD。在更高的能量（$\sqrt{s}=13$和 27 TeV）parton Reggeization 方法预测更大的横截面，高达$～15\%$和$～30\%$， 分别。