标题： 亮度测量中的XY分解偏差 显示英文标题

标题： XY Factorization Bias in Luminosity Measurements

摘要： 对于大多数高精度粒子物理实验，必须以最高精度知道亮度。 亮度由对撞束的粒子密度的卷积确定。 在特殊的范德梅尔横向束分离扫描中，卷积函数沿水平和垂直轴进行采样，目的是确定束流卷积并获得绝对亮度校准。 为此，分别用给出最佳描述的解析函数对亮度计率的范德梅尔数据在两个方向进行拟合。 假设二维卷积形状可分离，就可以从两个一维拟合中计算出它。 XY 分离分析的任务是检验这一假设，并给出非可分离性对校准常数影响的定量度量，以提高亮度测量的准确性。 \newline 我们进行了一项专门分析，研究CMS实验在2022年在$\sqrt{s} = 13.6$~TeV下收集的质子-质子数据中的XY不可分离性。 详细检查了束流卷积函数的形状，研究了各种偏差，并选择最佳拟合的解析二维函数，最终得到修正值及其不确定性。 显示英文摘要

摘要： For most high-precision experiments in particle physics, it is essential to know the luminosity at highest accuracy. The luminosity is determined by the convolution of particle densities of the colliding beams. In special van der Meer transverse beam separation scans, the convolution function is sampled along the horizontal and vertical axes with the purpose of determining the beam convolution and getting an absolute luminosity calibration. For this purpose, the van der Meer data of luminometer rates are separately fitted in the two directions with analytic functions giving the best description. With the assumption that the 2D convolution shape is factorizable, one can calculate it from the two 1D fits. The task of XY factorization analyses is to check this assumption and give a quantitative measure of the effect of nonfactorizability on the calibration constant to improve the accuracy of luminosity measurements. \newline We perform a dedicated analysis to study XY non-factorization on proton-proton data collected in 2022 at $\sqrt{s} = 13.6$~TeV by the CMS experiment. A detailed examination of the shape of the bunch convolution function is presented, studying various biases, and choosing the best-fit analytic 2D functions to finally obtain the correction and its uncertainty.