The resonant photoproduction of the electron-positron pairs on a nucleus near a surface of the X-ray pulsar was studied theoretically. The main feature of the processes, which are responsible for the formation of the electron-positron fluxes, is a capability to occur in a resonant way in the electromagnetic field of the X-ray pulsar. One of the properties of the resonant case is that the initial process of second order in the fine structure constant in an external field effectively reduces into two successive processes of the first order due to the fact that in the resonant conditions intermediate virtual electron (positron) becomes a real particle. It is shown that the resonances are possible only when the initial gamma quantum energy is more than the threshold energy, which significantly depends on the number of absorbed photons of an external electromagnetic field. Additionally, in the resonant conditions, the energies of the particles depend on the outgoing angle of a positron (channel A) or an electron (channel B). It is shown that the resonant differential cross section has an extremely large magnitude in units $\alpha Z^2{r}_e^2$. A mechanism to explain the presence of anomalous fluxes of ultrarelativistic positrons near the surface of an X-ray pulsar was proposed.

中文翻译：

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X射线脉冲星场中超相对论电子-正电子对在核上的光产生中的共振效应。

理论上研究了电子-正电子对在X射线脉冲星表面附近的原子核上的共振光产生。负责形成电子-正电子通量的过程的主要特征是能够以共振方式在X射线脉冲星的电磁场中发生。谐振情况的一个特性是，由于在谐振条件下中间虚拟电子（正电子）的存在，使外部场中精细结构常数中的第二阶初始过程有效地减少为两个第一阶连续过程。变成一个真实的粒子。结果表明，只有当初始伽马量子能量大于阈值能量时，共振才可能发生。这很大程度上取决于外部电磁场吸收的光子数。另外，在共振条件下，粒子的能量取决于正电子（通道A）或电子（通道B）的出射角。结果表明，共振微分截面的单位大小非常大。$\alpha {ž}^2{\mathrm{[R}}_{Ë}^2$。提出了一种解释超相对论正电子在X射线脉冲星表面附近存在异常通量的机制。