EGRET LIMITS ON HIGH-ENERGY GAMMA-RAY EMISSION FROM X-RAY-SELECTED AND LOW-ENERGY GAMMA-RAY-SELECTED SEYFERT-GALAXIES

被引:40
作者
LIN, YC
BERTSCH, DL
DINGUS, BL
FICHTEL, CE
HARTMAN, RC
HUNTER, SD
KANBACH, G
KNIFFEN, DA
MATTOX, JR
MAYERHASSELWANDER, HA
MICHELSON, PF
VONMONTIGNY, C
NOLAN, PL
SCHNEID, E
SREEKUMAR, P
THOMPSON, DJ
机构
[1] NASA,GODDARD SPACE FLIGHT CTR,UNIV SPACE RES ASSOC,GREENBELT,MD 20771
[2] MAX PLANCK INST EXTRATERR PHYS,D-85748 GARCHING,GERMANY
[3] HAMPDEN SYDNEY COLL,HAMPDEN SYDNEY,VA 23943
[4] COMP SCI CORP,GRO SCI SUPPORT CTR,ASTRON PROGRAMS,GREENBELT,MD 20771
[5] GRUMMAN AEROSP CORP,BETHPAGE,NY 11714
关键词
GALAXIES; SEYFERT; GAMMA-RAYS; OBSERVATIONS;
D O I
10.1086/187069
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
A sample of 22 Seyfert galaxies, 11 type 1 and two type 2 galaxies selected according to their X-ray fluxes in the AGN survey catalogs of EXOSAT and Ginga, two additional type 1 galaxies for which detections in low-energy gamma rays have been reported in the past, plus six more type 1 galaxies and one unclassified Seyfert that have been studied by the OSSE collaboration, have been examined for high-energy gamma ray emission in observations by the EGRET telescope on the Compton Observatory. No high-energy gamma-ray emission has been detected from any of them. The 2 sigma upper limits of the gamma-ray fluxes above 100 MeV for these 22 Seyfert galaxies are given here. The significance of these negative results is discussed. Implications of the EGRET result for NGC 4151 are discussed in more detail.
引用
收藏
页码:L53 / L56
页数:4
相关论文
共 43 条
[41]  
THOMPSON DJ, 1993, IN PRESS APJ
[42]   THE EXOSAT SPECTRAL SURVEY OF AGN [J].
TURNER, TJ ;
POUNDS, KA .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1989, 240 (04) :833-880
[43]   VARIABLE X-RAY ABSORPTION IN NGC-4151 [J].
YAQOOB, T ;
WARWICK, RS ;
POUNDS, KA .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1989, 236 (01) :153-170