We have previously shown that AGN have a characteristic time-scale, Tb , whichscales roughly as Mmdot (ie mass/accretion rate in Eddington units). However therange of M and mdot covered is not large and hence the dependency on mdot couldvary between virgulmdot^(-0.6) and mdot^(-1.3) (90% confidence), with similar massuncertainties. Understanding this scaling relationship is crucial to ourunderstanding of the accretion process. Therefore, particularly as someresearchers have questioned any dependence on mdot, it is crucial to reduce theuncertainties by a factor of 2. The best way to do that is to add one orbit ofXMM observations to existing RXTE monitoring to determine Tb in 2 extreme AGN,one with mdot x10 lower, and 1 with mass x10 higher, than previously observed.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2009-11-11T21:05:46Z/2009-12-11T08:04:07Z
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, Prof Ian McHardy, 2011, 'Tightly constraining the Timescale-Mass-Accretion rate relationship in AGN', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-0lfal8y
