Related papers: Visual Observability of the Cassiopeia A Supernova
The distribution of elements produced in the inner-most layers of a supernova explosion is a key diagnostic for studying the collapse of massive stars. Here we present the results of a 2.4 Ms \textit{NuSTAR} observing campaign aimed at…
The rapid cooling of the neutron star in Cassiopeia A is speculated to arise from an enhanced neutrino emission caused by the onset of $^3P_2$-wave neutron superfluidity in the core. However, the neutrino emissivity due to Cooper-pair…
Two main physical mechanisms are used to explain supernova explosions: thermonuclear explosion of a white dwarf(Type Ia) and core collapse of a massive star (Type II and Type Ib/Ic). Type Ia supernovae serve as distance indicators that led…
The eruption of the recurrent nova U Scorpii on 28 January 2010 is now the all-time best observed nova event. We report 36,776 magnitudes throughout its 67 day eruption, for an average of one measure every 2.6 minutes. This unique and…
The effects of the interaction between Type Ia supernova ejecta and their circumstellar wind on the photometric properties of Type Ia supernovae are investigated. We assume that a hydrogen-rich, dense, and extended circumstellar matter…
VERITAS observed the supernova remnants Cassiopeia A (Cas A) and IC 443 during 2007, resulting in strong TeV detections of both sources. Cas A is a young remnant, and bright in both the radio and nonthermal X-rays, both tracers of…
Cassiopeia A (Cas A) supernova remnant shows strong radiation from radio to gamma-ray bands. The mechanism of gamma-ray radiation in Cas A and its possible contribution to PeV cosmic rays are still under debate. The X-ray imaging reveals an…
Cassiopeia A (Cas A) is the youngest known core-collapse supernova remnant (SNR) in the Galaxy and is perhaps the best-studied SNR in X-rays. Cas A has a line-rich spectrum dominated by thermal emission and given its high flux, it is an…
During the years 1838-1858, the very massive star {\eta} Carinae became the prototype supernova impostor: it released nearly as much light as a supernova explosion and shed an impressive amount of mass, but survived as a star.1 Based on a…
We propose that the observed cooling of the neutron star in Cassiopeia A is due to enhanced neutrino emission from the recent onset of the breaking and formation of neutron Cooper pairs in the 3P2 channel. We find that the critical…
V605 Aquilae is today widely assumed to have been the result of a final helium shell flash occurring on a single post-asymptotic giant branch star. The fact that the outbursting star is in the middle of an old planetary nebula and that the…
The optical observations of Ic-4 supernova (SN) 2016coi/ASASSN-16fp, from $\sim 2$ to $\sim450$ days after explosion, are presented along with analysis of its physical properties. The SN shows the broad lines associated with SNe Ic-3/4 but…
While it is generally accepted that Type Ia supernovae are the result of the explosion of a carbon-oxygen White Dwarf accreting mass in a binary system, the details of their genesis still elude us, and the nature of the binary companion is…
X-ray observations of the neutron star in the Cas A supernova remnant over the past decade suggest the star is undergoing a rapid drop in surface temperature of $\approx$ $2-5.5\%$. One explanation suggests the rapid cooling is triggered by…
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…
We examine observed heavy element abundances in the Cassiopeia A supernova remnant as a constraint on the nature of the Cas A supernova. We compare bulk abundances from 1D and 3D explosion models and spatial distribution of elements in 3D…
Transient surveys have recently discovered a class of supernovae (SNe) with extremely rapidly declining light curves. These events are also often relatively faint, especially compared to Type Ia SNe. The common explanation for these events…
The enigmatic X-ray emission from the bright optical star, $\gamma$ Cassiopeia, is a long-standing problem. $\gamma$ Cas is known to be a binary system consisting of a Be-type star and a low-mass ($M\sim 1\,M_\odot$) companion of unknown…
We revisit the case of SN2002ic that recently revived the debate about the progenitors of SNeIa after the claim of the unprecedented presence of hydrogen lines over a diluted SNIa spectrum. As an alternative to the previous interpretation,…
Type Ia supernovae are thought to be the outcome of the thermonuclear explosion of a carbon/oxygen white dwarf in a close binary system. Their optical light curve is powered by thermalized gamma-rays produced by the radioactive decay of…