At low luminosities, the X-ray spectra of neutron star (NS) LMXB transientsoften contain two components: one is due to thermal emission from the NS surfaceand is reasonably well-understood, while the other is a hard power-law ofunknown origin. Recently, observations of Cen X-4 in quiescence with XMM-Newtonand the Nuclear Spectroscopic Telescope Array (NuSTAR) have provided the firstlook at the broadband spectrum. The hard component is sharply cutoff above 10keV and is consistent with a bremsstrahlung emission mechanism. We propose ajoint XMM-Newton, NuSTAR, and Swift Target of Opportunity program to observe AqlX-1 in order to compare the broadband spectrum from this system to that of CenX-4.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2016-09-28T15:45:52Z/2016-09-28T23:41:43Z
Version
PPS_NOT_AVAILABLE
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 John Tomsick, 2017, 'Observing Aql X-1 to understand the hard X-ray emission from NS transients', PPS_NOT_AVAILABLE, European Space Agency, https://doi.org/10.5270/esa-xie59bd
