2003/01/16 by P. Kaaret, Philip Kaaret, Stephane Corbel +5 · 7 citations
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Black hole (networking) #Galaxy #Intermediate-mass black hole #Physics #Pulsars and Gravitational Waves Research #Star formation #Stellar black hole #Stellar mass #astro-ph
paper · pdf · doi:10.1126/science.1079610
published as Science 299 (2003) 365-367 · 8 pages, one color figure. appeared in Science 299: 365-367 (January 17, 2003)
openalex publication_date 2003/01/16 · arxiv created 2003/02/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The physical nature of ultraluminous x-ray sources is uncertain. Stellar-mass black holes with beamed radiation and intermediate 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.