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RXTE Observations of the SGR 1806-20 Steady Emission

D. Marsden·R. E. Rothschild·C. Kouveliotou·S. Dieters·J. van Paradijs
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Abstract

We discuss observations of the quiescent emission from the soft gamma repeater SGR 1806-20 by the Rossi X-ray Timing Explorer. We find that the 2-20 keV RXTE data is consistent with a constant spectral shape during both active bursting periods and periods of relative quiescence, and is best described by a nonthermal (power law) spectral shape. Using archival ASCA data we find that the quiescent spectrum of SGR 1806-20 is well fit over the energy range 1-30 keV by a power law of photon index 2.31 +/- 0.04, with thermal bremsstrahlung and Raymond-Smith models producing much worse fits to the data.

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D. Marsden, R. E. Rothschild, C. Kouveliotou, S. Dieters, J. van Paradijs. 1998-03-05. RXTE Observations of the SGR 1806-20 Steady Emission. https://arxiv.org/abs/astro-ph/9803056

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