Radio Emission from an Ultraluminous X-Ray Source
arXiv:astro-ph/0302182 · doi:10.1126/science.1079610
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.
8 pages, one color figure. appeared in Science 299: 365-367 (January 17, 2003)