等离子体中相对论电子的同步曲率辐射特性研究

Characteristics of the synchrotron radiation from relativistic electrons in plasma

根据同步曲率辐射理论推导了在等离子体环境中,不同磁场条件下的相对论性电子的吸收系数和发射系数表达式,计算了电子的发射强度,并且在此基础上研究了同步曲率辐射机制的脉泽效应.研究了两种磁场位型,第一种是强度均匀但弯曲的磁场,第二种是偶极磁场,结果发现了一些偶极磁场下特有的辐射特性.考虑到在天体的环境下电子具有的不同的能谱分布,分别选用了三种典型的能谱分布(幂率分布,高斯分布,热分布)进行了研究,通过计算负吸收和脉泽放大效应在发射强度上的表现后,发现在某些天体物理环境中,同步曲率辐射在等离子体中的确存在脉泽放大效应.这些研究结果对太阳系中行星外层辐射的研究和宇宙中的射电高亮温度等问题的研究可能提供有益的帮助.

According to synchrotron radiation theory, we derive the absorption coefcient, emission coefficient, and the emission intensity from relativistic electrons in the plasma under the different kinds of magnetic fields. Furthermore, we study the maser effect of the synchrotron radiation. The effects of two kinds of magnetic fields are investigated, the first kind is a curved magnetic field, but its strength is homogenous. The other is a dipole magnetic field. We find some special characteristics in the dipole magnetic field. Because of the uncertainty of the energy distribution spectrum of electrons, we choose three typical energy distribution spectra, namely the power law spectrum, Gauss spectrum and thermal spectrum. By calculating the emission intensity, we find the maser effect of synchron-curvature radiation under several kinds of astronomical condition. It is clearly shown that the maser emission of the synchrotron radiation does exist in plasma environment. These results could give some explanations for the atmospheric radiation of planets and might be helpful to solve the problems of the high brightness temperature of some radio sources.