New BeppoSAX-WFC results on superbursts

in't Zand, J. J. M.; Cornelisse, R.; Kuulkers, E.; Verbunt, F.; Heise, J.
Referencia bibliográfica

X-RAY TIMING 2003: Rossie and Beyond. AIP Conference Proceedings, Volume 714, pp. 253-256 (2004).

Fecha de publicación:
7
2004
Número de autores
5
Número de autores del IAC
0
Número de citas
8
Número de citas referidas
7
Descripción
Presently seven superbursters have been identified representing 10% of the total Galactic X-ray burster population. Four superbursters were discovered with the Wide Field Cameras (WFCs) on BeppoSAX and three with the All-Sky Monitor and Proportional Counter Array on RXTE. We discuss the properties of superbursters as derived from WFC observations. There are two interesting conclusions. First, the average recurrence time of superbursts among X-ray bursters that are more luminous than 10% of the Eddington limit is 1.5 yr per object. Second, superbursters systematically have higher α values and shorter ordinary bursts than most bursters that have not exhibited superbursts, indicating a higher level of stable thermonuclear helium burning. Theory predicts hitherto undetected superbursts from the most luminous neutron stars. We investigate the prospects for finding these in GX 17+2.