文章基本信息

标题：The nuclear region of the spiral galaxy M81
本地全文：下载
作者：N Bartel ; M F Bietenholz ; M P Rupen 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1995
卷号：92
期号：25
页码：11374-11376
DOI：10.1073/pnas.92.25.11374
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Very-long-baseline radio interferometry images of the nuclear region of the nearby spiral galaxy M81 reveal the most compact galactic core outside the Galaxy of which the size has been determined: 700 x 300 astronomical units (AU). The observations exclude a starburst or supernova interpretation for the core. Instead they favor an active galactic nucleus. There is evidence for a northeastern jet bent by approximately 35 degrees over a length scale from 700 to 4000 AU. The jet is, on average, directed toward an extended emission region, probably a radio lobe, about 1 kiloparsec (kpc) away from the core. A corresponding emission region was found in the southwest at a distance of only 30 pc from the core. The observed jet is extremely stable and likely to be associated with a steady-state channel. There is no detectable motion along the jet beyond the nominal value of -60 +/- 60 km.s-1. The level of activities in the core region of M81 is intermediate between that of SgrA* and that of powerful radio galaxies and quasars.