We study neutrino and antineutrino emission from the direct Urca process in neutron-star matter in the presence of strong magnetic fields. We calculate the neutrino emissivity of the direct Urca process, whereby a neutron converts to a proton, an electron and an antineutrino, or a proton-electron pair converts to a neutron-neutrino pair. We solve exact wave functions for protons and electrons in the states described with Landau levels. We find that the direct Urca process can satisfy the kinematic constraints even in density regions where this process could not normally occur in the absence of a magnetic field.

中文翻译：

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通过直接 Urca 过程在强磁化中子星物质中进行中微子和反中微子发射的相对论量子方法

我们研究了在强磁场存在下中子星物质中直接 Urca 过程的中微子和反中微子发射。我们计算直接 Urca 过程的中微子发射率，其中中子转化为质子、电子和反中微子，或质子-电子对转化为中子-中微子对。我们在朗道能级描述的状态下求解质子和电子的精确波函数。我们发现直接 Urca 过程可以满足运动学约束，即使在没有磁场的情况下该过程通常不会发生的密度区域也是如此。