Due to their super-Eddington (L_Edd) X-ray luminosity ULXs have long beenconsidered the ideal sample where to look for BHs of intermediate mass. Thediscovery of three ULXs showing pulsations unambiguously associated them to NSsexceeding 500 times their L_Edd. These discoveries challenge our understandingof accretion physics and pose a key question about the nature of the ULXs\: arethey a population hosting both BHs and NSs, or is there a dominant new NSpopulation with extreme properties? This proposal involves a large fraction ofthe ULX community and is aimed at answering the above question by tripling thenumber of ULXs where sensitive searches for X-ray pulsations and cyclotronfeatures can be carried out. We expect to detect 2-3 new PULXs, thus doubling the current sample.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2018-05-11T21:25:50Z/2018-12-30T10:30:18Z
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, Prof Gian Luca Israel, 2020, 'Taking the beat of the UNSeEN openParThe Ultraluminous NS populatioN of ULXsclosePar', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-govki6q
