CONSTRAINTS ON THE SIZE OF THE EMITTING REGION IN AN ACTIVE GALACTIC NUCLEUS

被引:17
作者
CZERNY, B [1 ]
JAROSZYNSKI, M [1 ]
CZERNY, M [1 ]
机构
[1] UNIV WARSAW OBSERV,PL-00478 WARSAW,POLAND
关键词
ACCRETION; ACCRETION DISKS; RADIATION MECHANISMS; THERMAL; RELATIVITY; QUASARS; INDIVIDUAL; Q; 2237+0305; GRAVITATIONAL LENSING;
D O I
10.1093/mnras/268.1.135
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The microlensing phenomenon observed in the quasar Q 2237 + 0305 strongly constrains the size of the region emitting in the optical band. It rules out a model of optical/UV emission produced in a single optically thin cloud. Both a model with a huge number of small optically thin cloudlets and a model with an accretion disc around a supermassive black hole are, however, marginally consistent with the data. An irradiated disc model can both meet the size requirements and reproduce the slope of the quasar spectrum, even if the effects of electron scattering in the atmosphere of the disc are taken into account. Future observations of colour changes in Q 2237 + 0305 are crucial to distinguish these two possibilities.
引用
收藏
页码:135 / 142
页数:8
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