Evidence for a Sudden Magnetic Field Reconfiguration in SGR 1900+14
Abstract
We report the detection of large flux changes in the persistent X-ray flux of SGR 1900+14 during its burst active episode in 1998. Most notably, we find a factor ~700 increase in the non-burst X-ray flux following the August 27th flare, which decayed in time as a power-law. Our measurements indicate that the pulse fraction remains constant throughout this decay. This suggests a global flux enhancement as a consequence of the August 27th flare rather than localized heating. While the persistent flux has since recovered to the pre-outburst level, the pulse profile has not. The pulse shape changed to a near sinusoidal profile within the tail of the August 27th flare (in gamma-rays) and this effect has persisted for more than 1.5 years (in X-rays). The results presented here suggest the magnetic field of the neutron star in SGR 1900+14 was significantly altered (perhaps globally) during the giant flare of August 27.
Cite
@article{arxiv.astro-ph/0101045,
title = {Evidence for a Sudden Magnetic Field Reconfiguration in SGR 1900+14},
author = {Peter M. Woods and Chryssa Kouveliotou and Ersin Gogus and Mark H. Finger and Jean Swank and Don A. Smith and Kevin Hurley and Christopher Thompson},
journal= {arXiv preprint arXiv:astro-ph/0101045},
year = {2009}
}
Comments
17 pages, accepted for publication in ApJ