Related papers: He-accreting WDs as SNe Ia Progenitors
A key tracer of the elusive progenitor systems of Type Ia supernovae (SNe Ia) is the detection of narrow blueshifted time-varying Na I D absorption lines, interpreted as evidence of circumstellar material (CSM) surrounding the progenitor…
Hydrogen-rich matter has been added to a CO white dwarf of initial mass 0.516 \msun at the rates $10^{-8}$ and $2\times 10^{-8}$ \msun \yrm1, and results are compared with those for a white dwarf of the same initial mass which accretes pure…
Type Ia supernovae (SNe Ia) play a crucial role as standardizable cosmological candles, though the nature of their progenitors is a subject of active investigation. Recent observational and theoretical work has pointed to merging white…
We propose a formation channel for the previously unexplained helium-rich subdwarf O (He-rich sdO) stars in which post-subdwarf B (sdB) stars (i.e. hybrid COHe white dwarfs) reignite helium burning in a shell after gaining matter from their…
There is still considerable debate over the progenitors of type Ia supernovae (SNe Ia). Likewise, it is not agreed how single white dwarfs with masses less than ~0.5 Msun can be formed in the field, even though they are known to exist. We…
The symbiotic channel of Type Ia supernovae progenitors is crucial for explaining the observed circumstellar material in some Type Ia supernovae. While extensive numerical and observational efforts have been dedicated to exploring the…
The question of the nature of the progenitor of Type Ia supernovae (SNe Ia) is important both for our detailed understanding of stellar evolution and for their use as cosmological probes of the dark energy. Much of the basic features of SNe…
The recent detection of H-alpha emission in the supernova Type Ia SN 2002ic could be taken to mean that the elusive progenitor systems of Type Ia supernovae have finally been identified. At first glance, the observation appears to support a…
Relatively uniform light curves and spectral evolution of Type Ia supernovae (SNe Ia) have led to the use of SNe Ia as a ``standard candle'' to determine cosmological parameters, such as the Hubble constant, the density parameter, and the…
Type Ia supernovae (SNe Ia) have been used as excellent standardizable candles for measuring cosmic expansion, but their progenitors are still elusive. Here we report that the spectral diversity of SNe Ia is tied to their birthplace…
Dense, He-rich atmospheres of cool white dwarfs represent a challenge to the modeling. This is because these atmospheres are constituted of a dense fluid in which strong multi-atomic interactions determine their physics and chemistry.…
Thanks to the rapid increase of observations of Supernovae Ia, we may now claim that the Universe is accelerating. SN Ia are believed to be good standard candles, and after correcting the observations by various methods a precise Hubble…
The early lightcurves of Type Ia supernovae (SNe Ia) can be used to test predictions about their progenitor systems. If the progenitor system consists of a single white dwarf in a binary with a Roche-lobe-overflowing non-degenerate stellar…
Type Ia supernovae are thought to be thermonuclear explosions of accreting white dwarfs that reach a critical mass limit. Despite their importance as cosmological distance indicators, the nature of their progenitors has remained…
The evolution of binaries consisting of evolved main sequence stars (1 < M_d/Msun < 3.5) with white dwarf companions (0.7 < M_wd/Msun < 1.2) is investigated through the thermal mass transfer phase. Taking into account the stabilizing effect…
While it is generally accepted that Type Ia supernovae are the result of the explosion of a carbon-oxygen White Dwarf accreting mass in a binary system, the details of their genesis still elude us, and the nature of the binary companion is…
HD 49798 (a hydrogen depleted subdwarf O6 star) with its massive white dwarf (WD) companion has been suggested to be a progenitor candidate of type Ia supernovae (SNe Ia). However, it is still uncertain whether the companion of HD 49798 is…
We present a brief summary of the Single Degenerate Scenario for the progenitors of Type Ia Supernovae in which it is assumed that a low mass carbon-oxygen white dwarf is growing in mass as a result of accretion from a secondary star in a…
Cataclysmic Variables (CVs) and Symbiotic Binaries are close (or not so close) binary star systems which contain both a white dwarf (WD) primary and a larger cooler secondary star that typically fills its Roche Lobe. The cooler star is…
Although Type Ia supernovae (SNe Ia) play very important roles in many astrophysical fields, the exact nature of the progenitors of SNe Ia is still unclear. At present, the single degenerate (SD) model is a very likely one. Following the…