Related papers: Ultra-stripped Type Ic supernovae from close binar…
(abridged) When stripped from their hydrogen-rich envelopes, stars with initial masses between $\sim$7 and 11 M$_\odot$ develop massive degenerate cores and collapse. Depending on the final structure and composition, the outcome can range…
Stripped-envelope stars can be observed as Wolf-Rayet (WR) stars, or as less luminous hydrogen-poor stars with low mass loss rates and transparent winds. Both types are potential progenitors of Type I core-collapse supernovae (SNe). We use…
Transient surveys have recently discovered a class of supernovae (SNe) with extremely rapidly declining light curves. These events are also often relatively faint, especially compared to Type Ia SNe. The common explanation for these events…
Most stripped-envelope supernova progenitors are thought to be formed through binary interaction, losing hydrogen and/or helium from their outer layers. Ultra-stripped supernovae are an emerging class of transient which are expected to be…
I present an overview of optical observations (mostly spectra) of Type II, Ib, and Ic supernovae (SNe). 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…
Type IIn supernovae (SNe), a rare subclass of core collapse SNe, explode in dense circumstellar media that have been modified by the SNe progenitors at their last evolutionary stages. The interaction of the freely expanding SN ejecta with…
We investigate the possibility of a super-luminous Type Ic core-collapse supernovae producing a large amount of 56Ni. Very massive stars with a main-sequence mass larger than 100 Msun and a metallicity 0.001 < Z < 0.004 are expected to…
Stripped-envelope supernovae (SNe) are H-poor transients produced at the end of the life of massive stars that previously lost their H-rich envelope. Their progenitors are thought to be donor stars in mass-transferring binary systems, which…
We present a sample of Type Icn supernovae (SNe Icn), a newly-discovered class of transients characterized by their interaction with H- and He-poor circumstellar material (CSM). This sample is the largest collection of SNe Icn to date and…
Eruptive mass loss of massive stars prior to supernova (SN) explosion is key to understanding their evolution and end fate. An observational signature of pre-SN mass loss is the detection of an early, short-lived peak prior to the…
Some hydrogen-poor supernovae (SNe) are found to undergo interaction with dense circumstellar matter (CSM) that may originate from mass eruption(s) just prior to core-collapse. We model the interaction between the remaining star and the…
Type Ibn supernovae (SNe) are a mysterious class of transients whose spectra exhibit persistently narrow HeI lines, and whose bolometric light curves are typically fast evolving and overluminous at peak relative to standard Type Ibc SNe. We…
We investigate remnant neutron star masses (in particular, the minimum allowed mass) by performing advanced stellar evolution calculations and neutrino-radiation hydrodynamics simulations for core-collapse supernova explosions. We find…
Compact neutron star binary systems are produced from binary massive stars through stellar evolution involving up to two supernova explosions. The final stages in the formation of these systems have not been directly observed. We report the…
We present optical and infrared spectra of SN 1999ex that reveal a clear example of an intermediate Type Ib/c case. This suggests a continuous spectroscopic sequence between Type Ib and Type Ic supernovae. We report UBVRIz photometric…
The Type Ic supernovae are probably "nearly-nude" core collapse events. They are thus of special interest in terms of their evolutionary origin, but also as the source of potential clues to the explosion process that may not be obtained…
A large fraction of core-collapse supernovae (CCSNe), 30-50%, are expected to originate from the low-mass end of progenitors with $M_{\rm ZAMS}~= 8-12~M_\odot$. However, degeneracy effects make stellar evolution modelling of such stars…
Knowledge of the progenitors of core-collapse supernovae is a fundamental component in understanding the explosions. The recent progress in finding such stars is reviewed. The minimum initial mass that can produce a supernova has converged…
The properties of supernovae (SNe) are reviewed. It is shown that the observed characteristics of the morphological classes of SNe (types Ia, Ib/c, II) can be explained in terms of two basic explosion mechanisms, i.e. core collapse of…
We present the first unambiguous detection of helium emission lines in spectra of Type Ic supernovae (SNe Ic). The presence of He I lines, with full width at half maximum ~ 2000 km/s, and the distinct absence of any other intermediate-width…