arXiv subjects

M. J. S. Smith

Publications and source records attributed to M. J. S. Smith.

21 records · Page 2Linked to original sources

arXiv1999

Long term BeppoSAX-WFC monitoring of GRS 1758-258

Following a series of deep observations of the Galactic Bulge region performed with the Wide Field Cameras on board BeppoSAX, it has been possible to study throughout a long time period a number of persistent X-ray sources. We report on the behaviour of GRS 1758-258, an X-ray binary suggested as a black hole candidate on the basis of its timing and spectral characteristics. The source has been monitored for almost 2 years since August 1996; preliminary results of the data analysis are shown hereafter.

astro-ph↗

arXiv1998

X-ray bursts from 1RXS J170930.2-263927 = XTE J1709-267

We report evidence of type-I X-ray bursting activity from the transient 1RXS J170930.2-263927 when it was in outburst early 1997. This identifies the source as a probable low-mass X-ray binary containing a neutron star. The error boxes of the detected bursts and of the persistent emission, as obtained with the Wide Field Cameras on board the BeppoSAX satellite, rule out an association with the proposed radio counterpart (Hjellming & Rupen 1997).

astro-ph↗

arXiv1998

Gamma-Ray Burst 980329 and its X-Ray Afterglow

GRB 980329 is the brightest gamma-ray burst detected so far with the Wide Field Cameras aboard BeppoSAX, both in gamma-rays and X-rays. With respect to its fluence (2.6 X 10**-5 erg/s/cm**2 in 50 to 300 keV) it would be in the top 4% of gamma-ray bursts in the 4B catalog (Meegan et al. 1998). The time-averaged burst spectrum from 2 to 20 and 70 to 650 keV can be well described by the empirical model of Band et al. (1993). The resulting photon index above the break energy is exceptionally hard at -1.32 +/- 0.03. An X-ray afterglow was detected with the narrow-field instruments aboard BeppoSAX 7 h after the event within the error box as determined with the Wide Field Cameras. Its peak flux is (1.4 +/- 0.2) X 10**-12 erg/s/cm**2 (2 to 10 keV). The afterglow decayed according to a power law function with an index of -1.35 +/- 0.03. GRB 980329 is characterized by being bright and hard, and lacking strong spectral evolution.

astro-ph↗