The Type Ia Supernovae Progenitor Problem: Searching for Progenitors in the Milky Way
Abstract
One of the most active areas of current astrophysical research is the search for the progenitors of Type Ia supernovae. Understanding the nature(s) of the progenitors is crucial if we are to use these supernovae to conduct high-precision measurements of the history of cosmic expansion, because in order to confirm them as standardizable candles we need to understand the mechanism by which they are produced. Type Ia supernovae occur when carbon/oxygen white dwarfs explode, having gained mass either by accretion from a companion or by merging with another white dwarf. The white dwarfs in all Type Ia progenitors must go through a stage of high-rate accretion and possibly of nuclear burning. They should then be detectable as bright objects, with luminosities as high as a few times 1038 erg s-1. Furthermore, whatever the correct model(s), more than 1000 bright progenitors (and other systems that may be equally bright but in which the white dwarf does not reach the critical mass) are expected in the Milky Way. We are conducting a comprehensive search through archived data to identify unusual bright sources that may correspond to white dwarfs accreting at high rates. A significant fraction of the progenitors may appear as x-ray sources that are either supersoft or quasisoft some of the time. We have therefore searched the ROSAT, Chandra, and XMM databases to identify all such soft sources in the Milky Way that are detectable from Earth. We report on our results and their implications.
- Publication:
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American Astronomical Society Meeting Abstracts #221
- Pub Date:
- January 2013
- Bibcode:
- 2013AAS...22114229B