Radio spectra of selected compact sources in the nucleus of M82

被引：51

作者：

Allen, ML ^{[1
]}

Kronberg, PP ^{[1
]}

机构：

[1] Univ Toronto, Dept Astron, Toronto, ON M5S 3H8, Canada

来源：

ASTROPHYSICAL JOURNAL | 1998年 / 502卷 / 01期

关键词：

galaxies : individual (M82); galaxies : starburst; radio continuum : galaxies; supernova remnants;

D O I：

10.1086/305894

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We have determined detailed radio spectra for 26 compact sources in the starburst nucleus of M82, between 74 and 1.3 cm. Seventeen show low-frequency turnovers. One other has a thermal emission spectrum, and we identify it as an H II, region. The low-frequency turnovers result from absorption by interstellar thermal gas in M82. New information on the active galactic nucleus candidate 44.01+595 shows it to have a nonthermal falling power-law spectrum at the highest frequencies and that it is strongly absorbed below 2 GHz. We derive large magnetic fields in the supernova remnants of order (1-2)(1 + k)(2/7)phi(-2/7) mG; hence, large pressures in the sources suggest that the brightest ones are either expanding or are strongly confined by a dense interstellar medium. From the largest source in our sample we derive a supernova rate of 0.016 yr(-1).

引用

页码：218 / 228

页数：11

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