Contemporaneous IUE, EUVE, and high-energy observations of 3C 273

被引:14
作者
Ramos, E
Kafatos, M
Fruscione, A
Bruhweiler, FC
McHardy, IM
Hartman, RC
Titarchuk, LG
vonMontigny, C
机构
[1] GEORGE MASON UNIV,SPACE RES INST COMPUTAT SCI & INFORMAT,FAIRFAX,VA 22030
[2] HARVARD SMITHSONIAN CTR ASTROPHYS,CAMBRIDGE,MA 02138
[3] CATHOLIC UNIV AMER,DEPT PHYS,WASHINGTON,DC 20064
[4] UNIV SOUTHAMPTON,DEPT PHYS,SOUTHAMPTON SO9 5NH,HANTS,ENGLAND
[5] NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD 20771
[6] LANDESSTERNWARTE HEIDELBERG KONIGSTUHL,D-69117 HEIDELBERG,GERMANY
[7] GEORGE MASON UNIV,DEPT PHYS & ASTRON,FAIRFAX,VA 22030
[8] GEORGE MASON UNIV,CSI,CTR EARTH OBSERVING & SPACE RES,FAIRFAX,VA 22030
关键词
quasars; individual; (3C; 273); ultraviolet; galaxies; X-rays;
D O I
10.1086/304121
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present the results of our 1994 January and 1995 January observations of the quasar 3C 273 obtained with the International Ultraviolet Explorer (IUE) and the Extreme-Ultraviolet Explorer (EUVE). These observations were part of a large multiwavelength campaign to observe 3C 273 from radio through gamma-rays. Our 1995 January photometric observations with the EUVE Lexan/B Deep Survey (DS) instrument indicate strong evidence for variability, at a 99% confidence level, during the 12 day observing period. We have utilized ROSAT PSPC soft X-ray power-law models to correlate with EUVE count rates. Besides variations in the normalization level between both observations, our EUV count rates are consistent with a simple power-law model with spectral index alpha similar to 1.77 (F-v similar to v(-alpha)) that can be extrapolated from the soft X-rays to the EUV range. The active galactic nucleus 3C 273 is an important blazar to study because in our picture it reveals the presence of both disk and relativistic beam spectral contributions.
引用
收藏
页码:167 / 172
页数:6
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