We study the origin of quasi-harmonic emission bands with fine structure observed in the dynamic radiation spectra of high-frequency interpulses. The possible explanation of observed structure is based on the effect of double plasma resonance (DPR) at electron cyclotron harmonics realized in the magnetosphere of pulsar in a local radio emission source filled with non-relativistic plasma. The model of the source consists of neutral current sheet with a transverse magnetic field where plasma waves are generated due to DPR effect. It is shown that the emergence of emission bands and their frequency spacing are due to the inhomogeneity of the plasma and magnetic field along the current sheet, and their fine structure is due to the inhomogeneity of the current sheet in the direction orthogonal to it. Each quasi-harmonic emission band represents a system of elements of fine features of radiation that is generated by suprathermal electrons under DPR conditions. The observed upward drift of quasi-harmonic emission bands is due to the displacement of suprathermal electrons across the current sheet and an increase in the DPR frequencies with distance from the central plane of the layer.

中文翻译：

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蟹状脉冲星高频脉冲间动态谱中精细结构准谐波发射带的起源

我们研究了在高频脉冲的动态辐射光谱中观察到的具有精细结构的准谐波发射带的起源。观察到的结构的可能解释是基于在脉冲星的磁层中实现的电子回旋谐波的双等离子体共振（DPR）效应，在充满非相对论性等离子体的局域射电发射源中。源模型由具有横向磁场的中性电流片组成，其中由于 DPR 效应产生等离子波。结果表明，发射带的出现及其频率间隔是由于等离子体和磁场沿电流片的不均匀性，其精细结构是由于电流片与其正交方向的不均匀性。每个准谐波发射带代表一个由超热电子在 DPR 条件下产生的辐射精细特征的元素系统。观察到的准谐波发射带的向上漂移是由于超热电子在电流片上的位移以及 DPR 频率随着距层中心平面的距离而增加。