非均匀喷流模型及其在BL Lac天体中的应用

发布时间：2018-03-09 04:02

  本文选题：星系　切入点：活动　出处：《天文学报》2013年03期 　论文类型：期刊论文

【摘要】：在非均匀锥形喷流模型中,电子数密度、磁场强度随着到喷流顶点的距离呈幂律分布.该模型能成功解释活动星系核喷流核心区域的平谱射电辐射,但已有的模型计算只适用于喷流运动方向与视线夹角很大的情况,所以需要建立适用于任何视角情况的非均匀锥形喷流辐射计算公式.普遍认为BL Lac天体中喷流的运动方向与视线夹角很小,推广后的非均匀喷流模型拟合了3个BL Lac天体的射电观测谱,确定了它们喷流中电子数密度、磁场强度等物理参数.研究结果表明观测辐射谱拐折频率确定出锥形喷流离黑洞最近距离,对于这3个BL Lac天体,它们的锥形喷流离黑洞最近距离约为Schwarzschild半径.
[Abstract]:In the inhomogeneous conical jet model, the electron number density and magnetic field intensity show a power law distribution with the distance from the top of the jet. The model can successfully explain the flat-spectrum radio radiation in the core region of the active galactic nucleus jet. However, the existing model can only be used in the case of a large angle between the direction of the jet and the line of sight. So it is necessary to establish a formula for calculating the inhomogeneous conical jet radiation suitable for any angle of view. It is generally believed that the angle between the direction of motion and the line of sight of the jet in BL Lac celestial bodies is very small. The radio observation spectra of three BL Lac objects were fitted by the generalized non-uniform jet model, and the electron number density in the jet was determined. The results show that the nearest distance of the conical jet from the black hole is determined by the observed radiation spectrum turning frequency, and for the three BL Lac objects, their closest distance from the black hole is about the Schwarzschild radius.
【作者单位】： 中国科学院上海天文台;中国科学院大学;
【基金】：国家自然科学基金项目(10773021,10833005),国家自然科学基金创新研究群体项目(10821302) 973项目(2007CB815402/403)资助
【分类号】：P157.7
，

本文编号：1586877