Eur Phys J C Part Fields. 2024;84(8):842. doi: 10.1140/epjc/s10052-024-13116-7. Epub 2024 Aug 21.
A measurement is presented of a ratio observable that provides a measure of the azimuthal correlations among jets with large transverse momentum . This observable is measured in multijet events over the range of - based on data collected by the CMS experiment in proton-proton collisions at a centre-of-mass energy of 13 , corresponding to an integrated luminosity of 134 . The results are compared with predictions from Monte Carlo parton-shower event generator simulations, as well as with fixed-order perturbative quantum chromodynamics (pQCD) predictions at next-to-leading-order (NLO) accuracy obtained with different parton distribution functions (PDFs) and corrected for nonperturbative and electroweak effects. Data and theory agree within uncertainties. From the comparison of the measured observable with the pQCD prediction obtained with the NNPDF3.1 NLO PDFs, the strong coupling at the Z boson mass scale is , where the total uncertainty is dominated by the scale dependence of the fixed-order predictions. A test of the running of in the region shows no deviation from the expected NLO pQCD behaviour.
给出了一个可观测比值的测量结果，该比值可用于衡量具有大横向动量的喷注之间的方位角关联。此可观测值是在质心能量为13 TeV的质子 - 质子碰撞中，基于CMS实验收集的数据，在多喷注事件中于(\sqrt{s})范围为4.4 - 11.0 TeV内进行测量的，对应积分亮度为134 fb⁻¹。将结果与蒙特卡罗部分子淋浴事件发生器模拟的预测进行比较，以及与使用不同部分子分布函数（PDFs）并针对非微扰和电弱效应进行校正后，在次领先阶（NLO）精度下的固定阶微扰量子色动力学（pQCD）预测进行比较。数据和理论在不确定性范围内相符。通过将测量的可观测值与使用NNPDF3.1 NLO PDFs获得的pQCD预测进行比较，在Z玻色子质量尺度下的强耦合为(\alpha_s(M_Z) = 0.1181 \pm 0.0006)，其中总不确定性主要由固定阶预测的尺度依赖性主导。在(M_Z)区域对(\alpha_s)跑动的检验表明，未偏离预期的NLO pQCD行为。
