We propose simultaneous optical (VLT/FORS2) and X-ray (XMM-Newton) observationsof the ultraluminous X-ray source (ULX) NGC 5408 X-1 (hereafter X-1) in order tosearch for the signatures of X-ray reprocessing in its accretion disk. Ourproposed observations will enable the first sensitive search for X-ray - opticalcorrelations in a ULX and will address key questions regarding the nature of theaccretor in X-1. For example, detection of an X-ray -- optical correlation, asignature of reprocessing, will establish that the optical flux is largelyproduced in the accretion disk and not the companion star. Measurement of X-rayoptical time lags can lead to a mass estimate via the techniques ofreverberation mapping.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2014-02-11T00:29:41Z/2014-02-13T10:23:35Z
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 Tod Strohmayer, 2015, 'A Search for X-ray Reverberation in the Ultraluminous X-ray Source NGC 5408 X-1', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-ywf1sou
