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The Distance of the Soft Gamma Repeater SGR 1806-20

S. Corbel·P. Wallyn·T. M. Dame·P. Durouchoux·W. A. Mahoney·O. Vilhu·J. E. Grindlay
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Abstract

We present CO(J=1-0) observations in the direction of the Soft Gamma Repeater SGR 1806-20 with the SEST telescope. We detected several molecular clouds, and we discuss in this paper the implications of these observations for the distance to the X-ray counterpart AX 1805.7-2025, the supernova remnant G10.0-0.3 and the very luminous O9-B2 star detected in the line of sight. The distance of SGR 1806-20 is estimated to be 14.5 +/- 1.4 kpc and this Soft Gamma Repeater is very likely associated with one of the brightest HII regions in the Galaxy, W31. The large size of G10.0-0.3 (25 x 38 pc) for a young supernova remnant possibly powered by a central pulsar (AX 1805.7-2025) indicates that G10.0-0.3 could be expanding in the very low density region produced by the wind of the blue star.

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S. Corbel, P. Wallyn, T. M. Dame, P. Durouchoux, W. A. Mahoney, O. Vilhu, J. E. Grindlay. 1996-12-19. The Distance of the Soft Gamma Repeater SGR 1806-20. https://doi.org/10.1086/303807

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