We calculate the time delay for photons propagating in a charged electron‐positron gas at finite temperature and in an external magnetic field with the final aim of studying the effect for photons in a neutron star magnetosphere. The dispersion relations are solved in terms of analytic functions, in the degenerate, strong magnetic field, and ultra‐relativistic limit. For fixed values of frequency, temperature, and chemical potential, we study the dependence of photon time delay with the magnetic field strength, as well as with distance. For the latter, we adopt a magnetic dipole configuration and obtain that, according to the expectation, photons of higher energy experience a minor time delay. Obtained results are compared with the previous ones obtained for the photon time delay in vacuum magnetosphere.

中文翻译：

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磁化磁层中的光子时间延迟

我们计算出光子在有限温度和外部磁场中在带电电子-正电子气体中传播的时间延迟，最终目的是研究光子在中子星磁层中的影响。通过解析函数，简并，强磁场和超相对论极限来求解色散关系。对于固定的频率，温度和化学势值，我们研究了光子时间延迟与磁场强度以及距离的关系。对于后者，我们采用磁偶极子配置，并根据预期获得的结果是，能量较高的光子会经历较小的时间延迟。将获得的结果与先前获得的真空磁层中光子时间延迟的结果进行比较。