|Title||The Origin of CAL 83 X-Ray Off-States|
|Author||Dr Thierry Lanz|
|Description||The close binary supersoft X-ray source CAL 83 is a most promising candidate of SN Ia progenitors. Our XMM-Newton and Chandra observations show a massive white dwarf, exhibit large amplitude short-term variations of the X-ray flux, and establish definitively its recurrent nature. We propose now to conduct a campaign with EPIC and OM on XMM-Newton to substantiate the correlation between X-ray and optical variations on a short, medium, and long-term basis. This campaign will trace the physical relation between the accretion disk and the white dwarf, and will discriminate between several models explaining the origin of CAL 83 off-states. XMM-Newton data will offer unique and timely insights into accretion and unstable nuclear burning during the last evolution stages of SN Ia progenitors.|
|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, 2009-06-10T00:00:00Z, 050086, 17.56_20190403_1200. https://doi.org/10.5270/esa-q97s5o8|