耀变体在射电波段的偏振研究

Polarization Study of Blazar in Radio Frequency Band

利用UMRAO数据库22个耀变体源的偏振数据,根据Lazarian&Pogosyan理论模型分析研究了耀变体射电波段的偏振随波长的变化,得出不同类的耀变体偏振随波长变化的原因。结果表明,与Lazarian&Pogosyan理论模型吻合较好。由此得出如下结论:(1)反常去偏振耀变体源中反常法拉第旋光起主导作用,反常去偏振相对较少;(2)热辐射与同步辐射混合作用,高频波段的偏振度小于低频波段的偏振度(反常去偏振);(3)当被观测波段波长小于吸积盘热辐射对应的维恩波长时,高频波段的偏振度大于低频波段的偏振度(常规去偏振)。

In this paper,the polarization data of 22 ray sources in UMRAO database are used to analyze the change of polarization with wavelength in the radio frequency band on blazars,according to the theoretical model of Lazarian&Pogosyan.The cause of the change of polarization with wavelength about different class of blazars.The results show that it is in good agreement with the theoretical model of Lazarian&Pogosyan.From this,we conclude that:(1)the anomalous Faraday rotation in the anomalous depolarization source is dominant,and the anomalous depolarization is relatively small;(2)when the combination of thermal radiation and synchrotron radiation,the degree of polarization in the high frequency band is less than the of polarization degree in the low frequency band(abnormal depolarization);(3)when the wavelength of the observed frequency band is smaller than the Wien wavelength of the thermal radiation of the accretion disk,the polarization degree of the high frequency band is greater than the polarization degree of the low frequency band(conventional depolarization).