Shock-induced chiral magnetic effect
冲击波诱导的手征磁效应
Weak-interaction-mediated chiral imbalance generation in idealized massless electrons during core-collapse supernovae was once proposed to be the source of strong magnetic fields found in neutron stars. The effect goes by the name of chiral plasma instability. However, it was found that a finite electron mass damps out this process, inactivating the instability and preventing magnetic field growth. In this work, we show that the instability can survive in the presence of abrupt density and temperature perturbation that drives the system sufficiently far out of weak equilibrium. As an example, we work with such perturbations generated by shock waves which are common during both core collapse as well as neutron star mergers. We find that the chiral imbalance resulting from shock waves, under the right conditions of density and temperature, can sustain the chiral plasma instability despite the damping from the electron mass. Additionally, in an already magnetized medium, the chiral magnetic effect resulting from shock-wave density and temperature perturbation can generate substantial Ohmic heating. Our results imply that shock waves generated in core-collapse supernovae and merging neutron stars can act as a source of strong heating in a magnetized medium as well as chiral plasma instability.
展开 ▾重新审视有限电子质量下 CPI 失效的既有结论:强冲击波造成的密度/温度跳变可产生足够大的手征化学势,使 CPI 指数增长成为可能,并在磁化介质中产生可与激波本底热相比甚至更高的欧姆加热。
早期 Akamatsu+ 2013 曾设想核坍缩超新星中弱相互作用造成的手征不平衡可驱动手征等离子体不稳定性,解释中子星强磁场;但 Grabowska+ 2015 指出电子质量带来的手征翻转会更快耗散不平衡,使 CPI 难以生效。Kaplan+ 2017 推测快速密度涨落可能为 CPI 维持条件,Sigl+ Leite 2016 也讨论过核物质密度涨落的手征后果。本文用冲击波 Rankine-Hugoniot 跳变提供具体产生机制,表明足够强的激波可让手征不平衡在与电子质量阻尼的竞争中存续,并把 Sen+ Vaidya 2026 提出的欧姆加热延伸至冲击波磁化介质。未来需在数值模拟中加入中微子俘获、非简并 Urca 率、相变及更可靠的有限温高密 EoS,以判断中子星并合和超新星中这些效应是否真的可观。
预印本 2026-02-24 · 刊出 2026-08-17 · 收录 2026-08-22