We propose a deep observation of DEM L71, a middle-aged Type Ia SNR in the LMC,primarily using the Reflection Grating Spectrometers (RGS). Previous XMM-Newtonand Chandra studies of this SNR revealed the centrally-peaked emission from theFe-rich ejecta, indicating that the whole supernova ejecta have been heated bythe reverse shock. Our analysis of the existing RGS data indicates an unusuallylow Ni/Fe mass ratio, although its uncertainties are somewhat large.Theoretically, such low Ni/Fe ratio is expected only for a thermonuclearexplosion of a sub-Chandrasekhar-mass white dwarf (sub-MCh WD). With thisproposed observation, we will put a stringent constraint on the Ni/Fe ratio,providing the first robust evidence of the sub-MCh progenitor for a single Type Ia SN/SNR.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2022-04-12T22:04:08Z/2022-04-14T11:14:18Z
Version
19.17_20220121_1250
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 Hiroya Yamaguchi, 2023, 'Providing the first evidence of a sub-MCh progenitor for the Type Ia SNR DEM L71', 19.17_20220121_1250, European Space Agency, https://doi.org/10.57780/esa-aj2t90o
