THE CONSTANT INNER-DISK RADIUS OF LMC X-3: A BASIS FOR MEASURING BLACK HOLE SPIN
- 9 July 2010
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal Letters
- Vol. 718 (2), L117-L121
- https://doi.org/10.1088/2041-8205/718/2/l117
Abstract
The black hole binary system LMC X-3 has been observed by virtually every X-ray mission since the inception of X-ray astronomy. Among the persistent sources, LMC X-3 is uniquely both habitually soft and highly variable. Using a fully relativistic accretion disk model, we analyze hundreds of spectra collected during eight X-ray missions that span 26 years. For a selected sample of 391 RXTE spectra, we find that to within approximate to 2% the inner radius of the accretion disk is constant over time and unaffected by source variability. Even considering an ensemble of eight X-ray missions, we find consistent values of the radius to within approximate to 4%-6%. Our results provide strong evidence for the existence of a fixed inner-disk radius. The only reasonable inference is that this radius is closely associated with the general relativistic innermost stable circular orbit. Our findings establish a firm foundation for the measurement of black hole spin.Keywords
This publication has 38 references indexed in Scilit:
- MEASURING THE SPIN OF GRS 1915+105 WITH RELATIVISTIC DISK REFLECTIONThe Astrophysical Journal, 2009
- Angular Momentum Transport in Accretion Disks and Its Implications for Spin Estimates in Black Hole BinariesThe Astrophysical Journal, 2008
- Testing Accretion Disk Theory in Black Hole X‐Ray BinariesThe Astrophysical Journal, 2006
- A Grid of Relativistic, Non‐LTE Accretion Disk Models for Spectral Fitting of Black Hole BinariesThe Astrophysical Journal Supplement Series, 2006
- Advection‐Dominated Accretion and the Spectral States of Black Hole X‐Ray Binaries: Application to Nova Muscae 1991The Astrophysical Journal, 1997
- Spectral variations of LMC X-3 observed with GINGAThe Astrophysical Journal, 1993
- Evidence for Black Holes in Stellar Binary SystemsAnnual Review of Astronomy and Astrophysics, 1992
- Discovery of a long-term periodic variation in LMC X-3The Astrophysical Journal, 1991
- Discovery of a massive unseen star in LMC X-3The Astrophysical Journal, 1983
- Robust Locally Weighted Regression and Smoothing ScatterplotsJournal of the American Statistical Association, 1979