近日，德国杜塞尔多夫大学的C. Müller及其研究小组与德国耶拿大学的M. Zepf等人合作并取得一项新进展。经过不懈努力，他们揭示非微扰区域中非线性布赖特-惠勒对产生中激光聚焦和辐射反应对粒子谱的影响。相关研究成果已于2024年10月23日在国际知名学术期刊《物理评论A》上发表。

在这项理论研究中，研究人员探讨了激光聚焦、辐射反应以及宽轫致辐射γ光谱对产生的电子对能量和角度分布的影响。理解这些固有反应特性的作用可为实验检测策略和数据解释提供相关见解。

研究表明，考虑辐射反应会导致粒子能量分布变窄，与忽略辐射能量损失的情况相比，其最大值会显著移向更低的能量。宽轫致辐射光谱对粒子分布的形状也有显著影响，而在所考虑的参数范围内，激光聚焦的相应影响则相对温和。

据悉，即将开展的实验旨在探测由包含吉电子伏特（GeV）γ光子的轫致辐射脉冲和高强度激光脉冲碰撞所产生的强场布赖特-惠勒（Breit-Wheeler）电子对。

附：英文原文

Title: Impact of laser focusing and radiation reaction on particle spectra from nonlinear Breit-Wheeler pair production in the nonperturbative regime

Author: A. Eckey, A. Golub, F. C. Salgado, S. Villalba-Chávez, A. B. Voitkiv, M. Zepf, C. Müller

Issue&Volume: 2024/10/23

Abstract: Near-future experiments intend to detect strong-field Breit-Wheeler pair creation from the collision between bremsstrahlung bursts containing GeV-γ quanta and high-intensity laser pulses. In this theoretical study, we investigate the influence of laser focusing, radiation reaction, and a broad bremsstrahlung  γ spectrum on the energy and angular distributions of created pairs. Understanding the role of these inherent reaction attributes provides relevant insights for experimental detection strategies and data interpretation. We show that the inclusion of radiation reaction leads to a narrowing of the particles' energy distribution, whose maximum is shifted to substantially lower energies as compared to the case in which radiative energy losses are ignored. The broad bremsstrahlung spectrum also has a distinct influence on the shape of the particle distributions, whereas the corresponding impact of laser focusing turns out to be rather moderate in the considered parameter regime.

DOI: 10.1103/PhysRevA.110.043113

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.043113