DISCOVERY OF A NEW BL LACERTAE OBJECT (1E1402.3 + 0416) WITH THE EINSTEIN-OBSERVATORY

被引:11
作者
STOCKE, J
LIEBERT, J
STOCKMAN, H
DANZIGER, J
LUB, J
MACCACARO, T
GRIFFITHS, R
GIOMMI, P
机构
[1] CNR,IST RADIOASTRON,I-40126 BOLOGNA,ITALY
[2] CTR ASTROPHYS,CAMBRIDGE,MA 02138
[3] EUROPEAN SO OBSERV,MUNCHEN,FED REP GER
关键词
Galaxies;
D O I
10.1093/mnras/200.1.27P
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
One (and only one) BLLac object, designated IE 1402.3 + 0416, has been so far discovered as part of an optical identification program for a complete sample of faint X-ray sources detected with the Einstein Observatory. Consistent with earlier X-ray discovered BLLacs, this object is blue (aopt - — 1) and radio weak (17mJy at 6 cm). The percentage of BLLacs in the faint extragalactic X-ray sample (2 per cent) is smaller than the percentage at higher X-ray fluxes (6 per cent). Over the same range in X-ray flux, the percentage of emission-line active galaxy nuclei (QSO + Seyferts) increases from 40 to 74 per cent. This suggests that BLLacs do not evolve in a manner similar to quasars (> 4a confidence level) and are, therefore, not substantial contributors (^ 5 per cent) to the X-ray background. © Royal Astronomical Society.
引用
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页码:P27 / &
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