Related papers: Pre-explosion helium shell flash in type Ia supern…
Type Ia supernovae (SNe) occur when a white dwarf (WD) explodes via runaway thermonuclear burning. Till date, major uncertainties remain regarding the nature of the explosion mechanism and its observable signatures. In this work, we study…
A popular model for Type Ia supernovae (SNe Ia) is the detonation of a CO white dwarf (WD) that is triggered by the prior detonation of a thin surface layer of helium, known as a double detonation (DD). We explore the unique early…
Normal type Ia supernovae (SNe) are thought to arise from the thermonuclear explosion of massive ($>0.8$ M$_\odot$) carbon-oxygen white dwarfs (WDs), although the exact mechanism is debated. In some models helium accretion onto a…
We argue that the multiple shells of circumstellar material (CSM) and the supernovae (SN) ejecta interaction with the CSM starting 59 days after the explosion of the Type Ia SN (SN Ia) PTF 11kx, are best described by a violent prompt…
We investigate the brightness distribution expected for thermonuclear explosions that might result from the ignition of a detonation during the violent merger of white dwarf (WD) binaries. Determining their brightness distribution is…
We investigate predicted circumstellar properties of Type Ia supernova progenitor systems with non-degenerate helium star donors. It has been suggested that systems consisting of a carbon+oxygen white dwarf and a helium star can lead to…
Recent observations suggest that some type Ia supernovae (SNe Ia) originate from the merging of two carbon-oxygen white dwarfs (CO WDs). Meanwhile, recent hydrodynamical simulations have indicated that the accretion-induced collapse may be…
The lack of hydrogen in spectra of type Ia supernovae (SN Ia) is often seen as troublesome for single-degenerate (SD) progenitor models. We argue that, since continued accretion of angular momentum can prevent explosion of the white dwarf,…
Abridged. In the double detonation scenario for Type Ia supernovae (SNe Ia) a detonation initiates in a shell of He-rich material accreted from a companion star by a sub-Chandrasekhar-mass White Dwarf (WD). This shell detonation drives a…
The nature of Type Ia Supernova (SN Ia) explosions remains an open issue, with several contending progenitor scenarios actively being considered. One such scenario involves a SN Ia explosion inside a planetary nebula (PN) in the aftermath…
Over-luminous type Ia supernovae (SNe Ia) show peculiar observational features, for which an explosion of a super-massive white dwarf (WD) beyond the classical Chandrasekhar-limiting mass has been suggested, largely based on their high…
Type Ia supernovae are thought to be the outcome of the thermonuclear explosion of a white dwarf in a close binary system. Two possible scenarios, not necessarily incompatible, have been advanced. One assumes a white dwarf that accretes…
Using 3D numerical hydrodynamical simulations we show that jets launched prior to type Ia supernova (SN Ia) explosion in the core-degenerate scenario can account for the appearance of two opposite lobes ('Ears') along the symmetry axis of…
The merger of two white dwarfs (WDs) has for many years not been considered as the favoured model for the progenitor system of type Ia supernovae (SNe Ia). But recent years have seen a change of opinion as a number of studies, both…
We calculate the expected number of type Ia supernovae (SN Ia) in the core-degenerate (CD) scenario and find it to match observations within the uncertainties of the code. In the CD scenario the super-Chandrasekhar mass white dwarf (WD) is…
Early excess emission observed in Type Ia supernovae (SNe Ia) within $\sim1$ day of explosion provides a critical window into their progenitor systems. In the present study, we investigate formation of the circumstellar matter (CSM) in…
Recent advances in constructing stellar evolution models of hydrogen-deficient post-asymptotic giant branch (AGB) stars are presented. Hydrogen-deficiency can originate from mixing and subsequent convective burning of protons in the deeper…
Merging carbon-oxygen (CO) white dwarfs are a promising progenitor system for Type Ia supernovae (SN Ia), but the underlying physics and timing of the detonation are still debated. If an explosion occurs after the secondary star is fully…
A unique feature of deflagration-to-detonation (DDT) white dwarf explosion models of SNe of type Ia is the presence of a strong shock wave propagating through the outer envelope. We consider the early emission expected in such models, which…
Type Ia supernovae (SNe) are believed to be thermonuclear explosions of white dwarf (WD) stars, but their progenitor systems and explosion mechanisms are still unclear. Here we focus on double degenerate systems, where two WDs are…