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arXiv · astro-ph/0302182

Radio Emission from an Ultraluminous X-Ray Source

Philip Kaaret·Stephane Corbel·Andrea H. Prestwich·Andreas Zezas
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Abstract

The physical nature of ultraluminous x-ray sources is uncertain. Stellar mass black holes with beamed radiation and intermediate mass black holes with isotropic radiation are two plausible explanations. We discovered radio emission from an ultraluminous x-ray source in the dwarf irregular galaxy NGC 5408. The x-ray, radio and optical fluxes as well as the x-ray spectral shape are consistent with beamed relativistic jet emission from an accreting stellar black hole. If confirmed, this would suggest that the ultraluminous x-ray sources may be stellar-mass rather than intermediate mass black holes. However, interpretation of the source as a jet-producing intermediate-mass black hole cannot be ruled out at this time.

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Philip Kaaret, Stephane Corbel, Andrea H. Prestwich, Andreas Zezas. 2003-02-10. Radio Emission from an Ultraluminous X-Ray Source. https://doi.org/10.1126/science.1079610

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