|Title||Monitoring of the extreme alpha_ox variations in the luminous NL QSO PHL 1092|
|Author||Dr Giovanni Miniutti|
|Description||During a 2008 XMM-Newton observation the luminous Narrow-Line quasar PHL 1092 showed a dramatic X-ray flux drop by a factor ~200 with respect to previous X-ray observations, becoming one of the most extreme X-ray weak QSO (alpha_ox = -2.44), after being X-ray "normal" (alpha_ox = -1.56) only 4.5 years earlier. The aim of this proposal is to continue our UV and X-ray monitoring of this extreme source with two 25 ks exposures (one for each visibility window, hence separated by about 6 months) to unveil the timescale over which transitions from X-ray weak to normal QSO states take place in this most extraordinary AGN.|
|Publication||Insights on the X-ray weak quasar phenomenon from XMM-Newton monitoring of PHL 1092 . Miniutti, G., Brandt, W. N., et all. . MNRAS . 425-1718 . 2012 . 2012MNRAS.425.1718M ,
Serendipitous UV source catalogues for 10 years of XMM and 5 years of Swift . Yershov, V. N., . Ap&SS . 354-97 . 2014 . 2014Ap&SS.354...97Y ,
Ensemble X-ray variability of active galactic nuclei. II. Excess variance and updated structure function . Vagnetti, F., Middei, R., et all. . A&A . 593-55 . 2016 . 2016A&A...593A..55V ,
The Million Optical - Radio-X-ray Associations (MORX) Catalogue . Flesch, Eric W., . PASA . 33-52 . 2016 . 2016PASA...33...52F ,
AGN spectral states from simultaneous UV and X-ray observations by XMM-Newton . Svoboda, J., Guainazzi, M., . A&A . 603-127 . 2017 . 2017A&A...603A.127S ,
|Instrument||EMOS1, EMOS2, EPN, OM, RGS1, RGS2|
|Mission Description||The European Space Agency's (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESA's 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 Earth's 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.
|Publisher And Registrant||European Space Agency|
|Credit Guidelines||European Space Agency, 2012-01-26T00:00:00Z, 065384, 17.56_20190403_1200. https://doi.org/10.5270/esa-870fx7v|