The magnification invariant of circularly-symmetric lens models  

作　　者：Cheng-Liang Wei Zhe Chu Yi-Ping Shu 

机构地区：[1]Purple Mountain Observatory,the Partner Group of MPI fur Astronomie,Nanjing 210033,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]School of Astronomy and Space Sciences,University of Science and Technology of China,Hefei 230029,China

出　　处：《Research in Astronomy and Astrophysics》2018年第7期63-72,共10页天文和天体物理学研究（英文版）

基　　金：supports of the National Natural Science Foundation of China(Nos.11403103,11603032,11333008 and 11273061);the 973 program(Nos.2015CB857003 and 2013CB834900);China Postdoctoral Science Foundation(2014M551681);the Natural Science Foundation of Jiangsu Province(No.BK20140050).

摘　　要：In the context of strong gravitational lensing, the magnification of an image is crucially important for constraining various lens models. For several commonly used quadruple lens models, the magnification invariants, defined as the sum of the signed magnifications of images, have been analytically derived when the image multiplicity is a maximum. In this paper, we further study the magnification of several disk lens models, including （a） exponential disk lens, （b） Gaussian disk lens, （c） modified Hubble profile lens, and another two of the popular three-dimensional symmetrical lens models, （d） NFW lens and （e） Einasto lens. We find that magnification invariant exists for each lens model. Moreover, our results show that magnification invariants can be significantly changed by the characteristic surface mass density kc.In the context of strong gravitational lensing, the magnification of an image is crucially important for constraining various lens models. For several commonly used quadruple lens models, the magnification invariants, defined as the sum of the signed magnifications of images, have been analytically derived when the image multiplicity is a maximum. In this paper, we further study the magnification of several disk lens models, including （a） exponential disk lens, （b） Gaussian disk lens, （c） modified Hubble profile lens, and another two of the popular three-dimensional symmetrical lens models, （d） NFW lens and （e） Einasto lens. We find that magnification invariant exists for each lens model. Moreover, our results show that magnification invariants can be significantly changed by the characteristic surface mass density kc.

关 键 词：gravitational lensing strong-methods NUMERICAL 

分 类 号：P141[天文地球—天体物理]