This report reviews the effort over several decades to observe the linear Breit–Wheeler process ( γγ→e+e− ) and vacuum birefringence (VB) in high-energy particle and heavy-ion collider experiment. This report, motivated by the STAR collaboration’s recent observations, attempts to summarize the key issues related to the interpretation of polarized γγ→l+l− measurements in high-energy experiments. To that end, we start by reviewing the historical context and essential theoretical developments, before focusing on the decades of progress made in high-energy collider experiments. Special attention is given to the evolution in experimental approaches in response to various challenges, to the demanding detector capabilities required to unambiguously identify the linear Breit–Wheeler process, and to the connections with VB. We close the report with a discussion, followed by a look at near-future opportunities for utilizing these discoveries and for testing quantum electrodynamics in previously unexplored regimes.

中文翻译：

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物理学进展报告：重离子碰撞中布赖特-惠勒过程和真空双折射的观察


本报告回顾了几十年来在高能粒子和重离子对撞机实验中观察线性布赖特-惠勒过程 (γγ→e+e−) 和真空双折射 (VB) 的努力。本报告受 STAR 合作最近观察的启发，试图总结与高能实验中偏振 γγ→+− 测量解释相关的关键问题。为此，我们首先回顾历史背景和基本理论发展，然后重点关注高能对撞机实验几十年来取得的进展。特别关注应对各种挑战的实验方法的演变、明确识别线性 Breit-Wheeler 过程所需的苛刻探测器能力以及与 VB 的连接。我们以讨论结束报告，然后探讨了利用这些发现以及在以前未探索的领域中测试量子电动力学的近期机会。