Radio Spectra of Selected Compact Sources in the Nucleus of M82
Radio Spectra of Selected Compact Sources in the Nucleus of M82
复制标题
M82 核中选定紧凑源的射电频谱
DOI：
10.1086/305894
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
P. Kronberg
中科院分区：
文献类型：
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作者：
M. Allen;P. Kronberg
我们已经确定了 M82 星暴核中 74 至 1.3 厘米之间 26 个致密源的详细射电光谱。十七次出现低频失误。另一种具有热发射光谱，我们将其识别为 H II 区域。低频翻转是由 M82 中的星际热气体吸收造成的。关于活跃星系核候选者 44.01+595 的新信息表明，它在最高频率下具有非热下降幂律谱，并且在 2 GHz 以下被强烈吸收。我们推导了 (1-2)(1 + k)2/7phi-2/7 mG 级超新星遗迹中的大磁场；因此，源头中的巨大压力表明最亮的恒星要么正在膨胀，要么受到致密星际介质的强烈限制。从我们样本中最大的源中，我们得出的超新星发生率为 0.016 yr-1。
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)2/7ϕ-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.