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Updated: May 13, 2026
10:35
Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
A black hole nova obscured by an inner disk torus
J M Corral-Santana1, J Casares, T Muñoz-Darias
1Instituto de Astrofísica de Canarias, La Laguna, S/C de Tenerife, Spain. jcorral@iac.es
Science (New York, N.Y.)
|March 2, 2013
Summary
Swift J1357.2-093313, a stellar-mass black hole, exhibits unusual dips due to an outward-moving toroidal structure. This finding offers new insights into accretion flows and jet formation in black hole systems.
Area of Science:
- Astrophysics
- X-ray Astronomy
- Black Hole Physics
Background:
- Stellar-mass black holes (BHs) are typically observed in X-ray binaries, which undergo violent outbursts.
- Most known galactic BHs do not exhibit eclipses, a surprising observation given random inclination distributions.
Purpose of the Study:
- To investigate the nature of the faint X-ray transient Swift J1357.2-093313.
- To explain the unusual observational properties, including deep optical dips without X-ray counterparts.
Main Methods:
- Spectroscopic analysis to determine the orbital period and properties of the system.
- High-time-resolution optical light curve analysis to study variability.
- Modeling of accretion disk structures and inclination effects.
Main Results:
- Spectroscopic evidence confirms Swift J1357.2-093313 hosts a black hole with a 2.8-hour orbital period.
- Optical light curves show significant dips unrelated to X-ray emission.
- The observed phenomena are consistent with an obscuring toroidal structure moving outward in the inner accretion disk at high inclination.
Conclusions:
- The presence of an outward-moving toroidal structure is proposed to explain the unique features of Swift J1357.2-093313.
- This structure is crucial for understanding inner accretion flows and jet collimation in stellar-mass black holes.
- The findings challenge previous assumptions about black hole binary inclinations and accretion disk morphology.
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