Spectral Analysis of the Black Hole Candidate 4U 1630-47

Technical Report · Thu Feb 05 00:00:00 EST 2004

DOI:https://doi.org/10.2172/826725· OSTI ID:826725

Saxena, R ^[1]

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1. SLAC

We performed spectral analysis on the 1999 X-ray outburst of the soft X-ray transient black hole candidate (BHC) 4U 1630-47, in order to learn about physical processes (such as changes in inner disk radius of the accretion disk) that manifest themselves as changes of state. This source goes through an outburst every 600-690 days, which is a very short time period compared with other transient X-ray sources, The overall shape of the outburst's light curve was very similar to that of the 1996 outburst, but noticeably different from that of the 1998 outburst. We fitted 47 observations of the outburst to a model consisting of a disk blackbody, inverse Comptonization power law, and Gaussian component, multiplied by an absorption constant and an overall normalization constant. We found that the BHC progressed from a low state to high, and then back to low during its outburst. This pattern is common to persistent sources, not transient sources. We also found that when the source is in the low state, the flux and hardness are anticorrelated, as is predicted by theory. However, when 4U 1630-47 is in the high state, it is unclear whether or not the flux and hardness are correlated as theory says they should be.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (US)
• Sponsoring Organization: USDOE Office of Science (US)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 826725
• Report Number(s): SLAC-PUB-9394
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
ACCRETION DISKS
BLACK HOLES
HARDNESS
SHAPE
TRANSIENTS
X-RAY SOURCES