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arXiv · 1502.03231

Detection of a Compact Nuclear Radio Source in the Local Group Elliptical Galaxy M32

Yang Yang·Zhiyuan Li·Loránt O. Sjouwerman·Q. Daniel Wang·Qiusheng Gu·Ralph P. Kraft·Feng Yuan
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Abstract

The Local Group compact elliptical galaxy M32 hosts one of the nearest candidate super-massive black holes (SMBHs), which has a previously suggested X-ray counterpart. Based on sensitive observations taken with the {\it Karl G. Jansky} Very Large Array (VLA), we detect for the first time a compact radio source coincident with the nucleus of M32, which exhibits an integrated flux density of $\sim$$47.3\pm6.1$ $μ$Jy at 6.6 GHz. We discuss several possibilities for the nature of this source, favoring an origin of the long-sought radio emission from the central SMBH, for which we also revisit the X-ray properties based on recently acquired {\sl Chandra} and {\sl XMM-Newton} data. Our VLA observations also discover radio emission from three previously known optical planetary nebulae in the inner region of M32.

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Yang Yang, Zhiyuan Li, Loránt O. Sjouwerman, Q. Daniel Wang, Qiusheng Gu, Ralph P. Kraft, Feng Yuan. 2015-06-12. Detection of a Compact Nuclear Radio Source in the Local Group Elliptical Galaxy M32. https://arxiv.org/abs/1502.03231

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