|Title||SEARCHING FOR 'CHANGING LOOK. SEYFERT GALAXIES|
|Author||Prof GIORGIO MATT|
|Description||With the aim of discovering more sources which change their appearance from Compton--thin (if Seyfert 2s) or unabsorbed (if Seyfert 1s) to reflection--dominated, we propose to observe, for 10 ks each, four objects which have been proposed to be the optical counterparts of X--ray sources in the Grossan LMA HEAO1 catalog. The four candidate counterparts have been later on observed with imaging X-ray instruments, and found on those occasions to be much fainter. The XMM- Newton observations, if catching the sources at much brighter fluxes than during the previous hard X--ray imaging observations, would confirm their transient nature.|
|Publication||No observations found associated with the current proposal|
|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, 2005-10-20T00:00:00Z, 020066, 17.56_20190403_1200. https://doi.org/10.5270/esa-c33dh8g|