Related papers: Supernova Polarization and the Type IIn Classifica…

We have analyzed multi-band light curves of 328 intermediate redshift (0.05 <= z < 0.24) type Ia supernovae (SNe Ia) observed by the Sloan Digital Sky Survey-II Supernova Survey (SDSS-II SN Survey). The multi-band light curves were…

The violent merger of two carbon-oxygen white dwarfs has been proposed as a viable progenitor for some Type Ia supernovae. However, it has been argued that the strong ejecta asymmetries produced by this model might be inconsistent with the…

As part of the European Supernova Collaboration we obtained extensive photometry and spectroscopy of the type Ia SN 2002dj covering epochs from 11 days before to nearly two years after maximum. Detailed optical and near-infrared…

Data are presently available on 156 supernovae (SNe) of known type that have occurred in spirals of types Sa-Sc having inclinations i < 70 degrees. The surface density distribution of SN Ibc + SN II is found to be an exponential with…

Type IIP supernovae (SNe IIP) are the most common class of core-collapse SNe. They often show rapid increase of polarization degree in the late phase. This time evolution is generally believed to originate from the emergence of an inner…

We investigate the influence of close neighbor galaxies on the properties of supernovae (SNe) and their host galaxies using 56 SNe located in pairs of galaxies with different levels of star formation (SF) and nuclear activity. The mean…

We present six epochs of spectropolarimetric observations and one epoch of spectroscopy of the Type Ib SN iPTF 13bvn. The epochs of these observations correspond to $-$10 to $+$61 days with respect to the {\it r}-band light curve maximum.…

We report near infrared (NIR) spectroscopic observations of twelve ``Branch-normal'' Type Ia supernovae (SNe Ia) which cover the wavelength region from 0.8-2.5 microns. Our sample more than doubles the number of SNe Ia with published NIR…

During the first several days after explosion, Type Ia supernova light curves probe the outer layers of the exploding star and therefore provide important clues for identifying their progenitors. We investigate how both the shallow…

Type I superluminous supernovae (SLSNe) are a diverse class of exceptionally bright massive star explosions, which typically exhibit absorption from ionised oxygen in their early spectra. While their photometric properties (luminosity and…

Study of the polarization of supernovae has suggested that the core collapse process may be intrinsically strongly asymmetric. There is a tentative trend for supernova with smaller envelopes showing more polarization, with Type Ic having…

Type IIn supernovae occur when stellar explosions are surrounded by dense hydrogen-rich circumstellar matter. The dense circumstellar matter is likely formed by extreme mass loss from their progenitors shortly before they explode. The…

Type Ia Supernovae (SNe) have been used by many to argue for an accelerated expansion of the universe. However, high velocity and polarized features in many nearby SNe Ia, and their inverse relation to luminosity, particularly for…

It has been suggested that multiple scattering on circumstellar dust could explain the non-standard reddening observed in the line-of-sight to Type Ia supernovae. In this work we use Monte Carlo simulations to examine how the scattered…

Type Ia supernovae (SNe Ia) are thermonuclear runaways in certain white dwarfs in binary systems. They have been extensively studied, yet their progenitor and explosion mechanisms remain poorly understood. We study a large sample of SNe Ia…

We present a new method to photometrically delineate between various sub-types of type Ia supernovae (SNe Ia). Using the color-stretch parameters, $s_{BV}$ or $s_{gr}$, and the time of i-band primary maximum relative to the B-band or g-band…

Recent observations suggest that Type IIn supernovae (SNe IIn) may exhibit late-time (>100 days) infrared (IR) emission from warm dust more than other types of core-collapse SNe. Mid-IR observations, which span the peak of the thermal…

The Type Ia SN 2000cx exhibited multiple peculiarities, including a lopsided B-band light-curve peak that does not conform to current methods for using shapes of light curves to standardize SN Ia luminosities. We use the parameterized…

Young Galactic supernova remnants (SNRs) are where we can observe closely the supernova (SN) ejecta and its interaction with circumstellar/interstellar medium. Therefore, they provide an opportunity to explore the explosion and the final…

We present the complete set of ultra-violet, optical and near-infrared photometry and spectroscopy for SN 2012ca, covering the period from 6~days prior to maximum light, until 531 days after maximum. The spectroscopic time series for SN…