Related papers: Supernova 1998S at 14 years Postmortem: Continuing…

The type IIn SN 1998S is one of the most remarkable core-collapse supernovae ever observed. It underwent a complex interaction with a substantial circumstellar medium, resulting in radiation at wavelengths from radio to X-rays. IR and…

We present late-time near-infrared (NIR) and optical observations of the type IIn SN 1998S. The NIR photometry spans 333-1242 days after explosion, while the NIR and optical spectra cover 333-1191 days and 305-1093 days respectively. The…

Near-infrared spectra (0.95 -- 2.4 micron) of the peculiar Type IIn supernova 1998S in NGC 3877 from 95 to 355 days after maximum light are presented. K-band data taken at days 95 and 225 show the presence of the first overtone of CO…

SN 2007od exhibits characteristics that have rarely been seen in a Type IIP supernova (SN). Optical V band photometry reveals a very steep brightness decline between the plateau and nebular phases of ~4.5 mag, likely due to SN 2007od…

Observations of the Type II-P (plateau) Supernova (SN) 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN…

SN 2008es is one of the rare cases of a Type II superluminous supernova (SLSN) showing no relatively narrow features in its early-time spectra, and therefore its powering mechanism is under debate between circumstellar interaction (CSI) and…

Ground-based and Hubble Space Telescope observations are presented for SN 1993J and SN 1998S. SN 1998S shows strong, relatively narrow circumstellar emission lines of N III-V and C III-IV, as well as broad lines from the ejecta. Both the…

We present a study of the dust associated with the core-collapse supernova SN~1995N. Infrared emission detected 14--15 years after the explosion was previously attributed to thermally echoing circumstellar material associated with the SN…

High-cadence surveys of the sky are revealing that a large fraction of red-supergiant (RSG) stars, which are progenitors of Type II-Plateau (II-P) supernovae (SNe), explode within circumstellar material (CSM). Such SNe II-P/CSM exhibit…

We present new {\it JWST}/MIRI MRS and Keck spectra of SN 1995N obtained in 2022--2023, more than 10,000 days after the supernova (SN) explosion. These spectra are among the latest direct detections of a core-collapse SN, both through…

Optical and ultraviolet observations of the Type IIn supernova 1995N at epochs between 321 and 1799 days after the explosion show three distinct velocity components. The narrow lines come from circumstellar gas and show both low and high…

Type IIn SNe show spectral evidence for strong interaction between their blast wave and dense circumstellar material (CSM) around the progenitor star. SN2010jl was the brightest core-collapse SN in 2010, and it was a Type IIn explosion with…

Supernova (SN) 2002hh was unusual among core-collapse SNe because it was highly reddened, and displayed a bright infrared (IR) excess due to radiatively heated dust in its circumstellar medium (CSM). Estimates for the mass of dust…

We present optical and NIR photometry and spectroscopy of SN 2013L for the first four years post-explosion. SN 2013L was a moderately luminous (M$_{r}$ = -19.0) Type IIn supernova (SN) that showed signs of strong shock interaction with the…

We present contemporaneous optical and infrared photometric observations of the type IIn SN 1998S covering the period between 11 and 146 days after discovery. The infrared data constitute the first ever infrared light curves of a type IIn…

The luminous Type IIn Supernova (SN) 2010jl shows strong evidence for the interaction of the SN ejecta with dense circumstellar material (CSM). We present observations of SN 2010jl for $t \sim 900$ d after its earliest detection, including…

SN2005ip was a TypeIIn event notable for its sustained strong interaction with circumstellar material (CSM), coronal emission lines, and IR excess, interpreted as shock interaction with the very dense and clumpy wind of an extreme red…

Observations of the type II SN 1996L reveal the presence of a slowly expanding (V~700$ km/s) shell at ~ 10^(16) cm from the exploding star. Narrow emission features are visible in the early spectra superposed on the normal SN spectrum.…

SN 2013df is a nearby Type IIb supernova that seems to be the spectroscopic twin of the well-known SN 1993J. Previous studies revealed many, but not all interesting properties of this event. Our goal was to add new understanding of both the…

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…