Magnification relations of quad lenses and applications on Einstein crosses

doi:10.1093/mnras/stw1614

CORC > 上海天文台 > 中国科学院上海天文台

	Magnification relations of quad lenses and applications on Einstein crosses
	Chu, Zhe 3; Li, G. L.3; Lin, W. P.1,2; Pan, H. X.3
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2016-10-01
卷号	461 期号:4 页码:4466-4476
关键词	Gravitational Lensing: Strong Supernovae: Individual: Sn Refsdal
ISSN号	0035-8711
DOI	10.1093/mnras/stw1614
英文摘要	In this work, we mainly study the magnification relations of quad lens models for cusp, fold and cross configurations. By dividing and ray-tracing in different image regions, we numerically derive the positions and magnifications of the four images for a point source lying inside of the astroid caustic. Then, based on the magnifications, we calculate the signed cusp and fold relations for the singular isothermal elliptical lenses. The signed fold relation map has positive and negative regions, and the positive region is usually larger than the negative region as has been confirmed before. It can also explain that for many observed fold image pairs, the fluxes of the Fermat minimum images are apt to be larger than those of the saddle images. We define a new quantity cross relation R-cross which describes the magnification discrepancy between two minimum images and two saddle images. Distance ratio d(sadd)/d(mini) is also defined as the ratio of the distance of two saddle images to that of two minimum images. We calculate the cross relations and distance ratios for nine observed Einstein crosses. In theory, for most of the quad lens models, the cross relations decrease as the distance ratios increase. In observation, the cross relations of the nine samples do not agree with the quad lens models very well, nevertheless, the cross relations of the nine samples do not give obvious evidence for anomalous flux ratio as the cusp and fold types do. Then, we discuss several reasons for the disagreement, and expect good consistencies for more precise observations and better lens models in the future.
WOS研究方向	Astronomy & Astrophysics
语种	英语
出版者	OXFORD UNIV PRESS
WOS记录号	WOS:000383514900087
内容类型	期刊论文
源URL	[http://119.78.226.72/handle/331011/32773]
专题	中国科学院上海天文台
通讯作者	Chu, Zhe
作者单位	1.Chinese Acad Sci, Shanghai Astron Observ, 80 Nandan Rd, Shanghai 200030, Peoples R China 2.Sun Yat Sen Univ, Sch Phys & Astron, Guangzhou 510275, Guangdong, Peoples R China 3.Chinese Acad Sci, Purple Mt Observ, 2 West Beijing Rd, Nanjing 210008, Jiangsu, Peoples R China
推荐引用方式 GB/T 7714	Chu, Zhe,Li, G. L.,Lin, W. P.,et al. Magnification relations of quad lenses and applications on Einstein crosses[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2016,461(4):4466-4476.
APA	Chu, Zhe,Li, G. L.,Lin, W. P.,&Pan, H. X..(2016).Magnification relations of quad lenses and applications on Einstein crosses.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,461(4),4466-4476.
MLA	Chu, Zhe,et al."Magnification relations of quad lenses and applications on Einstein crosses".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 461.4(2016):4466-4476.