Related papers: Supernova 2002ic: the collapse of a stripped-envel…

We report optical and near-infrared observations of SN 2012ca with the Public ESO Spectroscopy Survey of Transient Objects (PESSTO), spread over one year since discovery. The supernova (SN) bears many similarities to SN 1997cy and to other…

The discovery of SN 2002ic and subsequent spectroscopic studies have led to the surprising finding that SN 2002ic is a Type Ia supernova with strong ejecta-circumstellar interaction. Here we show that nearly 1 year after the explosion the…

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…

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…

We present results from the first high resolution, high S/N, spectrum of SN 2002ic. The resolved Halpha line has a P Cygni-type profile, clearly demonstrating the presence of a dense, slow-moving (100 km/s) outflow. We have additionally…

Many young, massive stars are found in close binaries. Using population synthesis simulations we predict the likelihood of a companion star being present when these massive stars end their lives as core-collapse supernovae (SNe). We focus…

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…

I briefly describe the Lick Observatory Supernova Search with the 0.76-m Katzman Automatic Imaging Telescope. I then present an overview of optical observations of Type II, IIb, Ib, and Ic supernovae (SNe), all of which are thought to arise…

The dominant mechanism and time scales over which stripped-envelope supernovae (SNe) progenitor stars shed their hydrogen envelopes are uncertain. Observations of Type Ib and Ic SNe at late phases could reveal the optical signatures of…

Many core collapse supernovae (SNe) with hydrogen-poor and low-mass ejecta, such as ultra-stripped SNe and type Ibn SNe, are observed to interact with dense circumstellar material (CSM). These events likely arise from the core-collapse of…

Supernova 2002ic was an atypical Type Ia supernova (SN Ia) with evidence for substantial amounts of hydrogen associated with the system. Contrary to previous claims, we show that its unusual properties can be understood within the framework…

We present multi-wavelength observations of SN2014C during the first 500 days. These observations represent the first solid detection of a young extragalactic stripped-envelope SN out to high-energy X-rays. SN2014C was the explosion of an…

Optical spectroscopy of the Type Ia supernova SN 2002ic obtained on 2003 June 27.6 UT, i.e., about 222 rest-frame days after explosion, is presented. Strong H emission indicates an interaction between the expanding SN ejecta and an H-rich…

SN 2017dio shows both spectral characteristics of a type-Ic supernova (SN) and signs of a hydrogen-rich circumstellar medium (CSM). Prominent, narrow emission lines of H and He are superposed on the continuum. Subsequent evolution revealed…

Type IIn supernovae (SNe IIn) are hydrogen-rich explosions embedded in dense circumstellar medium (CSM), which gives rise to their characteristic narrow hydrogen emission lines. The nature of their progenitors and pre-explosion mass loss…

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…

Type Ic supernovae, the explosions following the core collapse of massive stars that have previously lost their hydrogen and helium envelopes, are particularly interesting because of the link with long-duration gamma-ray bursts. Although…

When nuclear fuel in the core of a massive star with a zero-age main-sequence mass $M_{\rm ZAMS} \gtrsim 8M_\odot$ is exhausted, the central part of the iron or magnesium core collapses and forms a neutron star or a black hole. At the same…

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…

All types of supernovae (SNe), except Type Ia, have been observed to interact with their immediate circumstellar medium (CSM). This interaction can reveal their progenitor's histories, and constrain our ideas about the evolution of massive…