The close binary supersoft X-ray source CAL 83 is a most promising candidate ofSN Ia progenitors. Our XMM-Newton and Chandra observations show a massive whitedwarf, exhibit large amplitude short-term variations of the X-ray flux, andestablish definitively its recurrent nature. We propose now to conduct acampaign with EPIC and OM on XMM-Newton to substantiate the correlation betweenX-ray and optical variations on a short, medium, and long-term basis. Thiscampaign will trace the physical relation between the accretion disk and thewhite dwarf, and will discriminate between several models explaining the originof CAL 83 off-states. XMM-Newton data will offer unique and timely insights intoaccretion and unstable nuclear burning during the last evolution stages of SN Ia progenitors.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2007-05-13T22:03:32Z/2008-04-21T05:42:20Z
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 Thierry Lanz, 2009, 'The Origin of CAL 83 X-Ray Off-States', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-q97s5o8
