The progenitors of Type Ia supernovae have remained a mystery for decades. Whileit seems certain that the explosion of a C/O white dwarf is involved, thesecondary may be a non-degenerate star or another white dwarf. In the lattercase, the companion white dwarf has an orbital velocity of 1100-2400 km/s beforethe explosion, and retains this velocity following the explosion. A recentsearch for hypervelocity white dwarfs with Gaia has yielded several intriguingcandidates for runaway survivors from double-degenerate Type Ia explosions. Wepropose short XMM-Newton exposures of these white dwarfs to place the firstX-ray constraints on potential coronal X-ray emission from these stars.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2019-05-11T20:43:03Z/2019-05-16T00:22:30Z
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 Jimmy Irwin, 2020, 'Hypervelocity White Dwarfs\: Telltale Signatures of a Double-Degenerate Type IaquestionMark', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-pjcny8l
