Related papers: The Most Luminous Supernovae
We present and discuss the optical spectro-photometric observations of the nearby (z=0.087) Type I superluminous supernova (SLSN I) SN 2017gci, whose peak K-corrected absolute magnitude reaches Mg=-21.5 mag. Its photometric and…
Every supernova hitherto observed has been considered to be the terminal explosion of a star. Moreover, all supernovae with absorption lines in their spectra show those lines decreasing in velocity over time, as the ejecta expand and thin,…
During the first few days after explosion, Type II supernovae (SNe) are dominated by relatively simple physics. Theoretical predictions regarding early-time SN light curves in the ultraviolet (UV) and optical bands are thus quite robust. We…
Nebular-phase observations and spectral models of Type Ic superluminous supernovae are presented. LSQ14an and SN 2015bn both display late-time spectra similar to galaxy-subtracted spectra of SN 2007bi, and the class shows strong similarity…
Neutron stars are among the most fascinating astrophysical sources, being characterized by strong gravity, densities about the nuclear one or even above, and huge magnetic fields. Their observational signatures can be extremely diverse…
The Asiago Supernova Catalog is used to carry out a comparative study of supernova absolute-magnitude distributions. An overview of the absolute magnitudes of the supernovae in the current observational sample is presented, and the evidence…
Ultraviolet (UV), optical and near infrared (NIR) observations of the type IIP supernova (SN) 2007od are presented, covering from the maximum light to the late phase, allowing to investigate in detail different physical phenomena in the…
We report on the discovery and initial observations of the energetic type IIn supernova (SN), 2008fz. The optical energy emitted by SN 2008fz (based on the light curve over a 88 day period), is possibly the most ever observed for a…
The last ten years have opened up a new parameter space in time-domain astronomy with the discovery of transients defying our understanding of how stars explode. These extremes of the transient paradigm represent the brightest - called…
Supernova explosions are among the most energetic phenomena in the known universe. There are suggestions that cosmic rays up to EeV energies might be accelerated in the young supernova shell on time scales of a few weeks to years, which…
Optical and near-infrared observations of the Type Ic supernova (SN) 2004aw are presented, obtained from day -3 to day +413 with respect to the B-band maximum. The photometric evolution is characterised by a comparatively slow post-maximum…
We currently know about 30 magnetars: seemingly isolated neutron stars whose properties can be (in part) comprehended only acknowledging that they are endowed with magnetic fields of complex morphology and exceptional intensity-at least in…
Photometric and spectroscopic data for two Low Luminosity Type IIP Supernovae (LL SNe IIP) are presented. SN 2020cxd reaches a peak absolute magnitude $M_{r}$ = -13.90 $\pm$ 0.05 mag two days after explosion, subsequently settling on a…
Type Ia supernovae are bright stellar explosions thought to occur when a thermonuclear runaway consumes roughly a solar mass of degenerate stellar material. These events produce and disseminate iron-peak elements, and properties of their…
Magnetars comprise two classes of rotating neutron stars (Soft Gamma Repeaters (SGRs) and Anomalous X-ray Pulsars), whose X-ray emission is powered by an ultrastrong magnetic field, B ~ 10^15 G. Occasionally SGRs enter into active episodes…
Observations of Gaia16apd revealed extremely luminous ultraviolet emission among superluminous supernovae (SLSNe). Using radiation hydrodynamics simulations we perform a comparison of UV light curves, color temperatures and photospheric…
Supernova remnants (SNRs) are thought to be the most plausible sources of Galactic cosmic rays. One of the principal questions is whether they are accelerating particles up to the maximum energy of Galactic cosmic rays ($\sim$PeV). In this…
GRB 111209A, one of the longest Gamma-Ray Bursts (GRBs) ever observed, is linked to SN 2011kl, the most luminous GRB-Supernova (SN) detected so far, which shows evidence for being powered by a magnetar central engine. We place SN 2011kl…
We present optical photometry and spectroscopy of SN\,2019stc (=ZTF19acbonaa), an unusual Type Ic supernova (SN Ic) at a redshift of $z=0.117$. SN\,2019stc exhibits a broad double-peaked light curve, with the first peak having an absolute…
I discuss the lack of observational evidence that magnetars are formed as rapidly rotating neutron stars. Supernova remnants containing magnetars do not show the excess of kinetic energy expected for such a formation scenario, nor is there…