Related papers: Type Ib Supernovae are bluer than Type Ic Supernov…
In the last decade a number of rapidly evolving transients have been discovered that are not easily explained by traditional supernovae models. We present optical and UV data on onee such object, SN 2018gep, that displayed a fast rise with…
Type Ib/c supernovae (SNe Ib/c) mark the deaths of hydrogen-deficient massive stars. The evolutionary scenarios for SNe Ib/c progenitors involve many important physical processes including mass loss by winds and its metallicity dependence,…
The absolute visual magnitudes of three Type IIb, 11 Type Ib and 13 Type Ic supernovae (collectively known as stripped-envelope supernovae) are studied by collecting data on the apparent magnitude, distance, and interstellar extinction of…
By definition, a Type Ic supernova (SN Ic) does not have conspicuous lines of hydrogen or helium in its optical spectrum. SNe Ic usually are modelled in terms of the gravitational collapse of bare carbon-oxygen cores. We consider the…
The extent of envelope stripping in the progenitor stars is directly reflected in the diversity of spectral features observed in stripped-envelope supernovae (SESNe). Through extensive spectral observation and analysis, we aim to clarify…
We have used images and spectra of the Sloan Digital Sky Survey to examine the host galaxies of 519 nearby supernovae. The colors at the sites of the explosions, as well as chemical abundances, and specific star formation rates of the host…
We use the latest dataset of supernova (SN) host galaxies to investigate how the host properties -- stellar mass, star formation rate, metallicity, absolute magnitude, and colour -- differ across SN types, with redshift-driven selection…
We investigate the effect of mixing of radioactive nickel ($^{56}$Ni) on the early-time color evolution of Type Ib and Ic supernovae (SNe Ib/Ic) using multi-group radiation hydrodynamics simulations. We consider both helium-rich and…
The very peculiar abundance patterns observed in extremely metal-poor (EMP) stars can not be explained by ordinary supernova nucleosynthesis but can be well-reproduced by nucleosynthesis in hyper-energetic and hyper-aspherical explosions,…
This paper reports an environmental analysis of 41 uniformly-selected stripped-envelope supernovae (SESNe) based on deep ultraviolet-optical images acquired by the Hubble Space Telescope. Young stellar populations are detected in most SN…
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…
We present BVRI photometry and optical spectroscopy of two Type Ic supernovae SN 2007bg and SN 2007bi discovered in wide-field, non-targeted surveys and associated with sub-luminous blue dwarf galaxies. Neither SNe 2007bg nor 2007bi were…
The massive star origins for Type IIP supernovae (SNe) have been established through direct detection of their red supergiants progenitors in pre-explosion observations; however, there has been limited success in the detection of the…
Stripped envelope supernovae are a sub-class of core collapse supernovae showing several stages of H/He shell stripping that determines the class: H-free/He-poor SNe are classified as Type Ic, H-poor/He-rich are Type Ib, and H/He-rich are…
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…
Type Ibn supernovae (SNe) are a small yet intriguing class of explosions whose spectra are characterized by low-velocity helium emission lines with little to no evidence for hydrogen. The prevailing theory has been that these are the…
High-quality collections of Type II supernova (SN) light curves are scarce because they evolve for hundreds of days, making follow-up observations time consuming and often extending over multiple observing seasons. In light of these…
Due to high-cadence automated surveys, we can now detect and classify supernovae (SNe) within a few days after explosion, if not earlier. Early-time spectra of young SNe directly probe the outermost layers of the ejecta, providing insights…
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…
Identifying the progenitors of Type Ib and Type Ic supernovae requires knowing, among other things, whether SNe Ib eject hydrogen, and whether SNe Ic eject helium, and perhaps even hydrogen. Recently it has become clear that some SNe Ib do…