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A Chandra Spectroscopic Survey of Persistent Black Hole Candidates

W. Cui·Y. X. Feng·S. N. Zhang·M. W. Bautz·G. P. Garmire·N. S. Schulz
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Abstract

We present results from observations of persistent black hole candidates with the High Energy Transmission Gratings aboard the Chandra X-ray Observatory. The sources include LMC X-1, LMC X-3, GRS 1758-258, and Cyg X-1. Along with the published results on 1E1740.7-2942, we have completed a high-resolution spectroscopic survey of such systems. The observed X-ray spectra of LMC X-1 and LMC X-3 show no prominent discrete features, while absorption edges (Mg K and Si K) are detected in the spectrum of GRS 1758-258. The edges are likely to be of interstellar origin. In most cases, the X-ray continuum can be described well by models that are often adopted in low-resolution studies of black hole candidates: a multi-temperature disk spectrum plus a Comptonization component. However, the relative contribution of the two components varies greatly among different sources. For instance, only the disk component is present for LMC X-1 and GRS 1758-258, while the Comptonized component is required for other sources. We discuss general issues related to obtaining disk parameters from modeling X-ray continuum.

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W. Cui, Y. X. Feng, S. N. Zhang, M. W. Bautz, G. P. Garmire, N. S. Schulz. 2002-07-27. A Chandra Spectroscopic Survey of Persistent Black Hole Candidates. https://doi.org/10.1086/341548

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