We request an XMM-Newton and HST/STIS observation of GSN 069, an ultra-soft,unabsorbed, highly variable X-ray source optically classified as a Seyfert 2AGN. Its high Eddington ratio (0.5) makes GSN 069 an exceptional high Eddingtonratio ..true Seyfert 2 galaxy. candidate. The data so far suggest two possibleinterpretations\: 1) a recent re-activation of the AGN after a period of lowactivity or quiescence or 2) an unusual (but not unique) long-lived outburst dueto a Tidal Disruption Event (TDE). With our joint XMM/HST program we aim atclarifying the nature of this most exceptional source and derive constraints onthe formation and evolution of BLR, disc winds, and AGN X-ray coronae in thefirst scenario, or on the nature of rare sustained TDEs in the second.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2018-12-24T03:51:53Z/2018-12-24T21:26:53Z
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 Giovanni Miniutti, 2020, 'GSN 069: a recent AGN re-activation or a long-lasting Tidal Disruption Event', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-gvbrszn
