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Multi-wavelength observations of the Soft Gamma Repeater SGR 1900+14 during its April 2001 activation

C. Kouveliotou·A. Tennant·P. M. Woods·M. C. Weisskopf·K. Hurley·R. P. Fender·S. T. Garrington·S. K. Patel·E. Gogus
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Abstract

The soft-gamma repeater SGR 1900+14 became active on 18 April 2001 after about two years of quiescence; it had remained at a very low state of activity since the fall of 1998, when it exhibited extraordinary flaring. We have observed the source in the gamma and X rays with Ulysses and Chandra, and in the radio with MERLIN. We report here the confirmation of a two component X-ray spectrum (power law + blackbody), indicating emission from the neutron star surface. We have determined that there is a dust halo surrounding the source that extends up to >~ 100'' from the center of SGR 1900+14, due to scattering in the interstellar medium.

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C. Kouveliotou, A. Tennant, P. M. Woods, M. C. Weisskopf, K. Hurley, R. P. Fender, S. T. Garrington, S. K. Patel, E. Gogus. 2001-07-10. Multi-wavelength observations of the Soft Gamma Repeater SGR 1900+14 during its April 2001 activation. https://doi.org/10.1086/323496

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