We present the results of Chandra , RXTE , and VLA observations of SGR 1900+14 in the immediate aftermath of its 2001 April 18 giant flare event .
In the X-ray band we find the source in a pulsating and bursting state , with time-averaged 2–10 keV flux initially elevated by 20 % above the source ’ s previous quiescent periods .
In the radio we establish upper limits on the strength of any persistent post-flare emission of 0.7 and 0.1 mJy at 1.4 GHz and 8.0 GHz , respectively .
The position of the X-ray source is consistent , to approximately 1 arcsec precision , with the August 1998 VLA determination , and the one-dimensional X-ray profile is consistent with that of a point source .
The X-ray spectrum is best-fit by a two component power-law plus blackbody model , with fitted blackbody temperature kT _ { BB } \approx 0.5 keV and radius R _ { BB } \approx 1.5 km for an assumed distance of 5 kpc .
The spectral parameters of this thermal component are consistent with those reported for the source in quiescence , and the variations in the source flux we observe may be explained as variations in the power-law component alone , providing support for magnetar models of SGR 1900+14 .