The photon emission by an ultrarelativistic charged particle in extremely strong magnetic field is analyzed, with vacuum polarization and photon recoil taken into account. The vacuum polarization is treated phenomenologically via refractive index. The photon emission occurs in the synergic (cooperative) synchrotron-Cherenkov process [J. Schwinger, W. Tsai and T. Erber, Annals of Physics, 96 303 (1976)] which is similar to the synchrotron emission rather than to the Cherenkov one. For electrons, the effect of the vacuum polarization on the emission spectrum is not evident even beyond the probable onset of non-perturbative quantum electrodynamics (QED). However, the effect of the vacuum polarization on the emission spectrum can be observable for muons already at $\gamma B / B_S \approx 30$, with $\gamma$ the muon Lorentz factor, $B$ the magnetic field strength and $B_S$ the critical QED field. Nevertheless, vacuum polarization leads to only 10% enhancement of the maximum of the radiation spectrum.

中文翻译：

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极化真空中协同同步加速器-切伦科夫辐射的准经典方法

分析了超相对论带电粒子在极强磁场中的光子发射，并考虑了真空极化和光子反冲。真空极化通过折射率从现象学上得到处理。光子发射发生在协同（合作）同步加速器-切伦科夫过程中 [J. Schwinger, W. Tsai 和 T. Erber, Annals of Physics, 96 303 (1976)] 这类似于同步加速器发射而不是 Cherenkov 发射。对于电子，真空极化对发射光谱的影响即使超出非微扰量子电动力学 (QED) 的可能开始也并不明显。然而，真空极化对发射光谱的影响对于已经在 $\gamma B / B_S \approx 30$ 的 μ 子是可以观察到的，其中 $\gamma$ 是 μ 子的洛伦兹因子，$B$ 磁场强度和 $B_S$ 临界 QED 场。然而，真空极化仅导致辐射光谱最大值的 10% 增强。