A dataset provided by the European Space Agency

Name 080508


DOI https://doi.org/10.5270/esa-ee6vbby
Author Prof Ian McHardy
Description Recent Swift observations of 4 medium mass AGN show that UV-optical variations lag higher energies as expected from reprocessing of high energies by an accretion disc. However the measured disc sizes are 3x larger than expected from theory and in 2 AGN the X-rays lead the UV by more than expected. It is also unclear whether earlier poor X-ray-optical correlations in high accretion rate (mdot) AGN are just due to inadequate sampling. We have recently shown that, for low masses, XMM can measure the crucial X-ray-UV lag and correlation strength very simply. Here we request to observe 4 low mass AGN with a range of mdot to measure that crucial lag and, from the ground, also the X-ray-g-band lag, so that the above problems, and any variation with mass or mdot can be properly understood.
Publication No observations found associated with the current proposal
Instrument EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage 2017-06-02T20:43:18Z/2017-06-05T15:21:18Z
Version 17.56_20190403_1200
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.
Creator Contact https://www.cosmos.esa.int/web/xmm-newton/xmm-newton-helpdesk
Date Published 2018-06-29T22:00:00Z
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2018-06-29T22:00:00Z, 080508, 17.56_20190403_1200. https://doi.org/10.5270/esa-ee6vbby