佘楞科夫线状发射和类星体光谱

本文讨论了气体介质中的佘楞科夫效应,指出具有各向同性速度分布的相对论电子在稠密气体中运动时,将发生佘楞科夫线状发射,产生具有宽的、轮廓显著不对称的原子发射谱线。其短波边陡直而长波方向则平坦下降。对氢原子L_α线的计算表明,当气休密度达到N=5×10²⁰厘米^-3,L_α线的宽度将大于60埃。根据这一辐射机制,类星体的发射谱线便可得到较为满意的解释。关键词：

THE CERENKOV LINE RADIATION AND THE EMISSION-LINE SPECTRA OF QSOs

Cerenkov effect in gas medium is discussed. It is pointed out that the relativistic electrons with isotropic distribution of velocity, when moving through a dense gas, will produce the broad atomic emission-lines with a remarkably asymmetric profile, the continuum slope on its long wave side being quite flat and that on the short wave side very steep.Calculation for the hydrogen atom shows that the width of L_α line may be larger than 60? as the gas density reaches N = 5×10²⁰cm^-3. According to this radiation mec-. hanism, the emission-line spectra of QSO_s can be interpreted satisfactorily.
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