Most nearby galaxies host supermassive black holes, accreting at low rates inadvection-dominated flows, or ADAFs. Depending on accretion rate and mass loss,hard X-ray continua and emission lines at soft and hard X-rays are expected inthese systems. We propose XMM observations of the nearby low-power radiogalaxies NGC 4261 and NGC 6251, the only radio-loud AGN, along with M87, hostinga supermassive black hole of known mass and where an ADAF may be occurring. Ourproposed XMM observations will allow a detailed study of the hard X-ray continuaand Fe lines detected in the ASCA data of NGC 4261 and NGC 6251, constrainingthe ADAF.s dynamical and physical properties as a function of black hole massand luminosity.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2001-12-16T05:25:06Z/2002-03-26T23:56:53Z
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 Rita Sambruna, 2003, 'Low-luminosity accretion in NGC4261 and NGC6251', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-xi58joz
