We now know that some of the most luminous members of the ultraluminous X-raysource (ULX) population are actually powered by highly super-Eddington pulsars,making them the most extreme accretors known. Three such systems are now known\:M82 X-2, NGC 7793 P13, and NGC 5907 ULX. These sources all exhibit unusual.off.-states in which their X-ray flux drops by virgul2 orders of magnitude (ormore). These off-states are fairly rare, but recent monitoring with Swift showsthat NGC 5907 ULX is now entering one. Here we propose an ambitious series ofsix 60 ks observations of NGC 5907 ULX (360 ks in total) designed to determinethe nature of these events. This is of critical importance, as these off-statesmay offer a means to determine the magnetic fields of these systems.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2019-06-12T18:55:44Z/2020-11-07T15:37:06Z
Version
18.02_20200221_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 Dominc Walton, 2021, 'Determining the Nature of the Extreme Off-States in ULX Pulsars with NGC5907 ULX', 18.02_20200221_1200, European Space Agency, https://doi.org/10.57780/esa-d2kgv1r
