In a recent work done with XMM-Newton, we have discovered that ultraluminousX-ray sources (ULXs) have strong relativistic winds in agreement with thetheoretical predictions of high accretion rates. These winds can becomeoptically thick enough to block and reprocess the disk X-ray photons, making thesource appear as a soft thermal emitter or ultraluminous supersoft X-ray source(ULS). We want to test this hypothesis, by studying a ULX where the wind isalready causing significant absorption of the X-ray continuum. NGC 55 ULX is theoptimal target, a transitional object between ULXs and ULSs, which exhibitsseveral strong blueshifted emission and absorption lines, and we propose toobserve it for 250 ks to determine the velocity structure and location of its strong relativistic wind.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2018-11-17T09:05:01Z/2018-11-18T23:55:01Z
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 Ciro Pinto, 2019, 'From ultraluminous X-ray to ultraluminous soft sources\: NGC 55 ULX novel study', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-wmb6wte
