Related papers: Massive stars exploding in a He-rich circumstellar…

Supernovae (SNe) are thought to arise from two different physical processes. The cores of massive, short-lived stars undergo gravitational core collapse and typically eject a few solar masses during their explosion. These are thought to…

Supernova (SN) 2008D/XRT 080109 is considered to be the only direct detection of a shock breakout from a regular SN to date. While a breakout interpretation was favored by several papers, inconsistencies remain between the observations and…

We report on our discovery and observations of the Pan-STARRS1 supernova (SN) PS1-12sk, a transient with properties that indicate atypical star formation in its host galaxy cluster or pose a challenge to popular progenitor system models for…

When the ejecta of supernovae interact with the progenitor star's circumstellar environment, a strong shock is driven back into the ejecta, causing the material to become bright optically and in X-rays. Most notably, as the shock traverses…

To date, SN 2017ein is the only Type Ic supernova with a directly identified progenitor candidate. This candidate points to a very massive ($>$45 $M_\odot$) Wolf-Rayet progenitor, but its disappearance after the explosion of SN 2017ein…

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…

Type Ibn supernovae (SNe) are characterized by narrow helium (He I) lines from photons produced by the unshocked circumstellar material (CSM). About 80 SNe Ibn have been discovered to date, and only a handful have extensive observational…

Analyses of supernovae (SNe) have revealed two main types of progenitors: exploding white dwarfs and collapsing massive stars. We present SN2002bj, which stands out as different from any SN reported to date. Its light curve rises and…

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…

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…

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…

We present a photometric and spectroscopic analysis of the Type Ibn supernova (SN) 2024acyl. It rises to an absolute magnitude peak of about -17.58 mag in 10.6 days, and displays a rapid linear post-peak light-curve decline in all bands,…

We present late-time observations of the site of the Type Ibn supernova (SN) 2006jc acquired with the Hubble Space Telescope Advanced Camera for Surveys. A faint blue source is recovered at the SN position with brightness…

We present extensive radio and X-ray observations of SN\, 2012au, the energetic radio luminous supernova of type Ib that may be a link between subsets of hydrogen-poor superluminous and normal core-collapse supernovae. The observations…

We present new pre-maximum and late-time optical photometry of the Type Ia/IIn supernova 2002ic. These observations are combined with the published V-band magnitudes of Hamuy et al. (2003) and the VLT spectrophotometry of Wang et al. (2004)…

It is well known that massive stars (M > 8 M_sun) evolve up to the collapse of the stellar core, resulting in most cases as a supernova (SN) explosion. Their heterogeneity is related mainly to different configurations of the progenitor star…

Type Ibn supernova SN~2010al is explored to infer parameters of supernova and a circumstellar (CS) shell. The CS interaction model combined with the spectral model of 4600\AA\ blend suggests the explosion of a WR star with the energy of…

Type Ia supernovae (SNe Ia) correspond to the thermonuclear explosion of a carbon-oxygen white dwarf (C-O WD) star in a binary system, triggered by the accretion of material from another star, or the merger/collision with a secondary WD.…

SN 2014C was an unprecedented supernova (SN) that displayed a metamorphosis from Type Ib to Type IIn over $\sim$200 days. This transformation is consistent with a helium star having exploded in a cavity surrounded by a dense shell of the…

We present spectroscopic and photometric observations and analysis of SN 2024abvb, a peculiar transitional Type Ibn/Icn supernova located at an unusually large projected distance from its host galaxy (21.5 kpc). SN 2024abvb displays an…