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Published on: May 2, 2018
Radio emission from an ultraluminous x-ray source.
Philip Kaaret1, Stephane Corbel, Andrea H Prestwich
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA. pkaaret@cfa.harvard.edu
Science (New York, N.Y.)
|January 18, 2003
Summary
Radio emission detected from an ultraluminous X-ray source suggests it may be a stellar-mass black hole with a relativistic jet. This finding could indicate that many such sources are stellar, not intermediate-mass, black holes.
Area of Science:
- Astronomy and Astrophysics
- High-Energy Astrophysics
- Black Hole Physics
Background:
- The nature of ultraluminous X-ray sources (ULXs) remains uncertain, with two leading hypotheses: stellar-mass black holes emitting beamed radiation or intermediate-mass black holes with isotropic radiation.
- Distinguishing between these possibilities is crucial for understanding black hole populations and accretion physics.
Purpose of the Study:
- To investigate the physical nature of ultraluminous X-ray sources by searching for radio emission.
- To determine if observed ULXs are powered by stellar-mass or intermediate-mass black holes.
Main Methods:
- Observation of radio emission from the ultraluminous X-ray source in NGC 5408 using radio telescopes.
- Analysis of X-ray, radio, and optical fluxes.
- Characterization of the X-ray spectral shape.
Main Results:
- Detection of radio emission from the ULX in NGC 5408.
- Observed X-ray, radio, and optical fluxes are consistent with beamed relativistic jet emission.
- The X-ray spectral shape aligns with this jet emission model.
Conclusions:
- The findings support the hypothesis that this ULX is an accreting stellar-mass black hole powering a relativistic jet.
- If confirmed, this suggests that ULXs may predominantly be powered by stellar-mass black holes.
- An interpretation as a jet-producing intermediate-mass black hole remains a possibility and cannot be excluded.
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