English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

There is wide agreement that Type Ia supernovae (used as standard candles forcosmology) are associated with the thermonuclear explosions of white dwarfstars. The nuclear runaway that leads to the explosion could start in a whitedwarf gradually accumulating matter from a companion star until it reaches theChandrasekhar limit, or could be triggered by the merger of two white dwarfs ina compact binary system. The X-ray signatures of these two possible paths arevery different. Whereas no strong electromagnetic emission is expected in themerger scenario until shortly before the supernova, the white dwarf accretingmaterial from the normal star becomes a source of copious X-rays for ~1e7 yrbefore the explosion. This offers a means of determining which path dominates.Here we report that the observed X-ray flux from six nearby elliptical galaxiesand galaxy bulges is a factor of ~30-50 less than predicted in the accretionscenario, based upon an estimate of the supernova rate from their K-bandluminosities. We conclude that no more than ~5 per cent of Type Ia supernovaein early type galaxies can be produced by white dwarfs in accreting binarysystems, unless their progenitors are much younger than the bulk of the stellarpopulation in these galaxies, or explosions of sub-Chandrasekhar white dwarfsmake a significant contribution to the supernova rate.

An upper limit on the contribution of accreting white dwarfs to the type Ia supernova rate