Cygnus X-1: shedding light on the spectral variability of a black hole
Abstract
The knowledge of the spectral state of a black hole is essential for the interpretation of data from black holes in terms of their emission models. Based on pointed observations of Cyg X-1 with the Rossi X-ray timing Explorer (RXTE) that are used to classify simultaneous RXTE-ASM observations, we develop a scheme based on RXTE-ASM colors and count rates that can be used to classify all observations of this canonical black hole that were performed between 1996 and 2011. We show that a simple count rate criterion, as used previously, leads to a significantly higher fraction of misclassified observations. This scheme enables us to classify single INTEGRAL-IBIS science windows and to obtain summed spectra for the soft, intermediate and hard state with low contamination by other states.
Additional Information
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-ShareAlike. This work has been partially funded by the Bundesministerium für Wirtschaft und Technologie under Deutsches Zentrum für Luft- und Raumfahrt Grants 50 OR 1007 and 50 OR 1113 and by the European Commission through ITN 215212 "Black Hole Universe", was partially completed by LLNL under Contract DE-AC52-07NA27344. K.P. and D.M.M. acknowledge support from NASA grant NNX09AT28G for INTEGRAL's Cycle 7 Guest Observer Programme. The data analysis presented in this work was performed with ISIS 1.6.2 [5]. We thank John E. Davis for the development of the slxfig module used to prepare all figures in this work.Attached Files
Published - INTEGRAL_2012_050.pdf
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Additional details
- Eprint ID
- 89235
- Resolver ID
- CaltechAUTHORS:20180828-122925125
- Bundesministerium für Wirtschaft und Technologie (BMWi)
- Deutsches Zentrum für Luft-und Raumfahrt (DLR)
- 50 OR 1007
- Deutsches Zentrum für Luft-und Raumfahrt (DLR)
- 50 OR 1113
- European Commission
- ITN 215212
- Department of Energy (DOE)
- DE-AC52-07NA27344
- NASA
- NNX09AT28G
- Created
-
2018-08-30Created from EPrint's datestamp field
- Updated
-
2021-11-16Created from EPrint's last_modified field
- Caltech groups
- Space Radiation Laboratory
- Series Name
- Proceedings of Science
- Series Volume or Issue Number
- 176