Related papers: Circumstellar Shells in Absorption in Type Ia Supe…
The progenitors of Type Ia supernovae (SNe Ia) are debated, particularly the evolutionary state of the binary companion that donates mass to the exploding carbon-oxygen white dwarf. In previous work, we presented hydrodynamic models and…
The nature of the companion stars in Type Ia Supernova (SNe) progenitor systems remains unclear. One possible way to discriminate between different scenarios is the presence (or absence) of circumstellar material, the left overs from the…
Type Ia supernovae arise from the thermonuclear explosions of white dwarfs in multiple star systems. A rare sub-class of SNe Ia exhibit signatures of interaction with circumstellar material (CSM), allowing for direct constraints on…
Searches for circumstellar material around Type Ia supernovae (SNe Ia) are one of the most powerful tests of the nature of SN Ia progenitors, and radio observations provide a particularly sensitive probe of this material. Here we report…
Circumstellar interaction has been observed around all types of massive star supernovae, especially at radio and X-ray wavelengths. The interaction shells in Type Ib/c supernovae appear to be moving rapidly, although SN 1998bw remains the…
Type Ia-CSM supernovae (SNe) are a rare and peculiar subclass of thermonuclear SNe characterized by emission lines of hydrogen or helium, indicative of a high-density circumstellar medium (CSM). Their implied mass-loss rates of $\sim…
Na I D absorbing systems toward Type Ia supernovae (SNe Ia) have been intensively studied over the last decade with the aim of finding circumstellar material (CSM), which is an indirect probe of the progenitor system. However, it is…
We present X-shooter observations of a sample of 21 hydrogen-poor superluminous supernovae (SLSNe-I), spanning a redshift range of z=0.13-0.95, aimed at searching for shells of circumstellar material (CSM). Specifically, we focus on…
A growing subset of Type Ia supernovae (SNe Ia) show evidence for unexpected interaction with a dense circumstellar medium (SNe Ia-CSM). The precise nature of the progenitor, however, remains debated owing to spectral ambiguities arising…
The effects of the interaction between Type Ia supernova ejecta and their circumstellar wind on the photometric properties of Type Ia supernovae are investigated. We assume that a hydrogen-rich, dense, and extended circumstellar matter…
One of the key observables for determining the progenitor nature of Type Ia supernovae is provided by their immediate circumstellar medium, which according to several models should be shaped by the progenitor binary system. So far, X-ray…
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…
Among the important issues in identifying the progenitor system of Type Ia supernovae (SNe Ia), we focus mostly on circumstellar interaction in SN 2002ic, and give brief discussion on the controversial issues of the effects of rotation in…
Intergalactic type-Ia supernovae (SNe-Ia) have been discovered recently in rich galaxy clusters, likely the descendants of an intergalactic stellar population found in recent years through a variety of tracers. We estimate the observational…
Type Ia supernovae (SNe Ia) are thermonuclear explosions of degenerate white dwarf (WD) stars destabilized by mass accretion from a companion star, but the nature of their progenitors remains poorly understood. A way to discriminate between…
Variable NaI absorption lines have been reported in a number of type Ia supernovae (SNeIa). The presence of this circumstellar material suggests that cataclysmic variables (CVs) with a giant donor star may be the progenitors of these SNeIa…
SN 2002ic is a unique supernova which shows the typical spectral features of Type Ia supernovae (SNe Ia) near maximum light, but also apparent hydrogen features that have been absent in SNe Ia. We have calculated hydrodynamical models for…
We study a possibility of detection of circumstellar absorption lines of Na I D$_{1,2}$ and Ca II H,K in spectra of type IIP supernovae at the photospheric epoch. The modelling shows that the circumstellar lines of Na I doublet will not be…
I present an overview of optical observations (mostly spectra) of Type II supernovae. SNe II are defined by the presence of hydrogen, and exhibit a very wide variety of properties. SNe II-L tend to show evidence of late-time interaction…
The progenitor systems accounting for explosions of type Ia supernovae (SNe Ia) is still under debate. Symbiotic channel is one of the possible progenitor scenarios, in which the WDs in these systems increase in mass through wind accretion…