arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1811.07528hep-phphysics.atom-ph
收藏

真空中电子-正电子对产生的阈值效应:稳定化和纵向与横向动量共享

Threshold effects in electron-positron pair creation from the vacuum: Stabilization and longitudinal vs transverse momentum sharing

K. Krajewska, J. Z. Kamiński

摘要:

在量子场论的框架下,计算了随时间振荡的电场在真空中产生的电子-正电子对的动量分布。当电场的频率通过单光子阈值时,观察到这些分布的显著增强。在该阈值以下,这些对优先携带纵向动量,而在该阈值以上,它们倾向于携带横向动量。这样的动量共享对产生的对的数量有影响:它随着场频率的增加而快速增长,低于阈值,但在高于阈值时,它饱和在一个大致恒定的值。另一方面,在高于单光子阈值的固定频率下,对的数量与场强成二次方关系。即使对于大的电场,这种典型的微扰标度也成立。因此,微扰理论的有效性在这里扩展到导致产生具有大量横动量的粒子的过程。

英文摘要:

Momentum distributions of electron-positron pairs created from the vacuum by an oscillating in time electric field are calculated in the framework of quantum field theory. A pronounced enhancement of those distributions is observed as the frequency of the electric field passes across the one-photon threshold. Below that threshold the pairs preferentially carry a longitudinal momentum, while above the threshold they tend to carry a transverse momentum. Such momentum sharing has an impact on the number of produced pairs: It grows fast with increasing the field frequency below the threshold but it saturates at a roughly constant value above it. On the other hand, at the fixed frequency above the one-photon threshold, the number of pairs scales quadratically with the field strength. This typically perturbative scaling holds even for large electric fields. Thus, the validity of the perturbation theory is extended here to processes which result in creation of particles with substantial transverse momenta.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑