Thermonuclear bursts in systems accreting pure helium reveal the structure ofthe neutron star (NS) interiors. Without heating from steady H-burning betweenbursts, the burst recurrence times and energetics are more sensitive to thethermal properties and processes in the NS crust and core. Burst ignitionmodels predict longer burst recurrence times than observed which may be due tofractional covering of the accreted fuel on the NS surface, supported by recentanalyses of several bursts from 4U 172834. But other processes including steadyHe-burning or incomplete burning, may also be important. SimultaneousINTEGRAL/XMM observations of 4U 172834 allow measurements of the burstrecurrence time and accretion rate, to distinguish between these possibilities.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2013-10-02T01:25:12Z/2013-10-02T05:01:52Z
Version
17.56_20190403_1200
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earths atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
European Space Agency, Dr Duncan Galloway, 2014, 'Helium-rich thermonuclear bursts from the Slow Burster', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-stqsuwb
