RADIO-LOUD AND RADIO-QUIET QUASARS OBSERVED BY EXOSAT

被引:60
作者
LAWSON, AJ
TURNER, MJL
WILLIAMS, OR
STEWART, GC
SAXTON, RD
机构
关键词
GALAXIES-ACTIVE; GALAXIES-NUCLEI; QUASARS-GENERAL; RADIO CONTINUUM-GALAXIES; X-RAYS-GALAXIES;
D O I
10.1093/mnras/259.4.743
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present results from the spectral analysis of EXOSAT data on 31 quasars, 18 radio-loud and 13 radio-quiet. Simple power-law models with fixed (Galactic) absorption give acceptable fits to the spectra obtained in the 2-10 keV band. Using the results from these fits we have compared the distributions of spectral indices alpha for the radio-loud and radio-quiet quasars in the sample. We find that the X-ray spectrum is flatter for radio-loud quasars, alphaBAR = 0.66 +/- 0.07, and is consistent with a single power-law index for these objects. The radio-quiet group, however, shows a steeper average spectrum, alphaBAR = 0.90 +/- 0.11, and a wider spread of indices.
引用
收藏
页码:743 / 750
页数:8
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