Harland-Lang L A
Department of Physics and Astronomy, University College London, London, WC1E 6BT UK.
Eur Phys J C Part Fields. 2024;84(12):1332. doi: 10.1140/epjc/s10052-024-13685-7. Epub 2024 Dec 29.
We present the first calculation of photon-initiated pair production in the presence of non-zero anomalous magnetic ( ) and/or electric dipole ( ) moments of the lepton that accounts for the non-trivial interplay between these modifications with the soft survival factor and the possibility of dissociation of the hadron (proton or ion) beam. The impact of these is on general grounds not expected to have a uniform dependence on the value of , but in all previous analyses this assumption has been made. We have therefore investigated the importance of these effects in the context of photon-initiated pair production in both pp and PbPb collisions. This is in general found to be relatively small, at the percent level in terms of any extracted limits or observations of , such that these effects can indeed be safely ignored in existing experimental analyses. However, as the precision of such determinations increases in the future, the relevance of these effects will likewise increase. With this in mind we have made our calculation publicly available in the SuperChic Monte Carlo generator, including the possibility to simulate this process for varying without rerunning.
我们给出了在轻子存在非零反常磁矩（ ）和/或电偶极矩（ ）的情况下，光子引发的对产生的首次计算，该计算考虑了这些修正与软存活因子之间的非平凡相互作用以及强子（质子或离子）束解离的可能性。一般来说，预计这些因素对 值的依赖并非均匀，但在所有先前的分析中都做了这样的假设。因此，我们在质子 - 质子（pp）和铅 - 铅（PbPb）碰撞中光子引发的对产生的背景下，研究了这些效应的重要性。总体而言，发现这些效应相对较小，就任何提取的 极限或观测而言，处于百分之几的水平，以至于在现有实验分析中这些效应确实可以安全地忽略。然而，随着未来此类测定精度的提高，这些效应的相关性也会增加。考虑到这一点，我们已将计算结果在SuperChic蒙特卡罗发生器中公开提供，包括无需重新运行就能针对不同的 模拟此过程的可能性。
