Bursts from Gs 1826-238: a Clocked Thermonuclear Flashes Generator
نویسنده
چکیده
The transient X-ray source GS 1826-238 was monitored during five different observing periods between August 1996 and October 1998 with the BeppoSAX Wide Field Camera instrument in the framework of a deep observation of the Galactic Center region. A first detection of X-ray bursts from this source occurred, ruling out its previously suggested black hole candidacy and strongly suggesting the compact object to be a weakly magnetized neutron star. During the 2.5 years of monitoring, corresponding to ∼ 2.0 Ms observing time, 70 bursts were detected from the source. We here report a quasi-periodicity of 5.76 hr in the burst occurrence time which is present during all observations. This is the first example of quasi-periodic bursting over a period of years. It is in line with the history of a rather constant flux since the turn on in 1988 and points to a very stable accretion. Subject headings: binaries: close, stars: individual (GS 1826-238) — X-rays: bursts
منابع مشابه
Clocked Bursts From GS 1826 - 238
We report on the long term monitoring of the GINGA transient source GS 1826-238 performed with the BeppoSAX Wide Field Camera (WFC) instrument, during four different observing campaigns covering October 1996 September 1999. WFC detection of type-I bursting activity from the source ruled out its proposed Black Hole candidacy and clearly suggested the compact object related to GS 1826-238 to be a...
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