Polarimetric studies of stars with an infrared emission excess

被引:6
作者
Eritsyan, MA [1 ]
Hovhannessian, RK [1 ]
Hovhannessian, ER [1 ]
机构
[1] VA Ambartsumian Byurakan Astrophys Observ, Byurakan, Armenia
关键词
D O I
10.1023/A:1015342508921
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The results of polarimetric and IR (IRAS) observations of 24 B-A-F stars are given. Intrinsic polarization of the light from 11 of the 24 stars is observed. The degree of polarization for the other 13 stars is within the measurement errors. Two-color diagrams are also constructed. Front a comparison of the degree of polarization with the color index on the two-color diagrams it is seen that 8 of these 13 stars probably are of the "Vega type," while 5 are stars with gas-dust shells and/or disk-shells: It is shown that 6 of the aforementioned 11 stars with intrinsic polarization evidently are stars with gas-dust shells and/or disk-shells, while 5 of them (also including No. 24) are of the "Vega. type." It is also shown that the IR emission from 10 of the stars corresponds to a power-law distribution Fv proportional to valpha. This, fact may be explained both by, free free transitions of electrons and by thermal emission from dust grains in circumstellar gas-dust shells (disks).
引用
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页码:25 / 31
页数:7
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