ROSAT Observations of the Soft Gamma-Ray Burst Error Box Coincident with the Supernova Remnant N49
Abstract
The supernova remnant N49 in the Large Magellanic Cloud was observed in soft X-rays using the High Resolution Imager aboard the ROSAT satellite. A total 0.1-2.4 keV image of the nebula was obtained by the use of a pixon-based image deconvolution algorithm. Image analysis determined the position of the X-ray hot spot (RX J05260.3 -660433) coincident with the error box of the soft gamma-ray repeater SGR 0525-66. The position is R.A. (J2000) = 5^h^26^m^0.31^s^ and decl. (J2000) = - 66^deg^4'33.20" with an uncertainty of 5" in radius, due almost entirely to the ROSAT pointing uncertainty. This positional uncertainty is a factor of 2 smaller than that obtained from previous data. Examinations of optical images of N49 show no stellar sources coincident with the X- ray position of RX J05260.3 -660433, with an upper limit of m_V_ ~21 mag. We have searched for periodicity in the signal from RX J05260.3 - 660433 in the period range 7.5-8.5 s, the approximate period observed from this source during the 1979 March 5 gamma-ray burst. No evidence for ~8 s periodicity was found, and the upper limit on the pulsed fraction was determined to be 66%, for pulse profiles typical of X-ray pulsars. The overall counting rate from the hot spot was consistent with a constant signal over the ~2 yr duration of the ROSAT observations.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1996
- DOI:
- 10.1086/177883
- Bibcode:
- 1996ApJ...470..513M
- Keywords:
-
- GAMMA RAYS: BURSTS;
- ISM: INDIVIDUAL ALPHANUMERIC: SNR N49;
- GALAXIES: MAGELLANIC CLOUDS;
- STARS: PULSARS: GENERAL;
- X-RAYS: ISM