HARD X-RAY TESTS OF THE UNIFIED MODEL FOR AN ULTRAVIOLET-DETECTED SAMPLE OF SEYFERT-2 GALAXIES

被引:69
作者
MULCHAEY, JS
MUSHOTZKY, RF
WEAVER, KA
机构
[1] UNIV MARYLAND,DEPT ASTRON,COLLEGE PK,MD 20742
[2] NASA,GODDARD SPACE FLIGHT CTR,HIGH ENERGY ASTROPHYS LAB,GREENBELT,MD 20771
关键词
GALAXIES; NUCLEI; SEYFERT; ULTRAVIOLET; X-RAYS;
D O I
10.1086/186374
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
A ultraviolet-detected sample of Seyfert 2 galaxies shows heavy photoelectric absorption in the hard X-ray band. The presence of UV emission combined with hard X-ray absorption argues strongly for a special geometry which must have the general properties of the Antonucci & Miller unified model. The observations of this sample are consistent with the picture in which the hard X-ray photons are viewed directly through the obscuring matter (molecular torus?) and the optical, UV, and soft X-ray continuum are seen in scattered light. The large range in X-ray column densities implies that there must be a large variation in intrinsic thicknesses of molecular tori, an assumption not found in the simplest of unified models. Furthermore, constraints based on the cosmic X-ray background suggest that some of the underlying assumptions of the unified model are wrong.
引用
收藏
页码:L69 / L72
页数:4
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