Related papers: Time-dependent Effects in Photospheric-Phase Type …
We present five far- and near-ultraviolet spectra of the Type II plateau supernova, SN 2022acko, obtained 5, 6, 7, 19, and 21 days after explosion, all observed with the Hubble Space Telescope/Space Telescope Imaging Spectrograph. The first…
The whole set of INTEGRAL observations of type Ia supernova SN2014J, covering the period 19-162 days after the explosion has being analyzed. For spectral fitting the data are split into "early" and "late" periods covering days 19-35 and…
Type Ia supernovae (SNe Ia) arise from the thermonuclear explosion in binary systems involving carbon-oxygen white dwarfs (WDs). The pathway of WDs acquiring mass may produce circumstellar material (CSM). Observing SNe Ia within a few hours…
We study the properties of low-velocity material in the line of sight towards nearby Type Ia Supernovae (SNe Ia) that have measured late phase nebular velocity shifts (v_neb), thought to be an environment-independent observable. We have…
A new model grid containing 228,016 synthetic red supergiant explosions (Type II supernovae) is introduced. Time evolution of spectral energy distributions from 1 A to 50,000 A (100 frequency bins in a log scale) is computed at each time…
Dust is expected to form on a year timescale in core-collapse supernova (SN) ejecta. Its existence is revealed through an infrared brightening, an optical dimming, or a blue-red emission-line profile asymmetry. To investigate how the dust…
We compare model calculations with observations of supernovae at late times to infer the time evolution of temperature, ionization and line emission. Here we mainly report on our results from our modeling of SN 1987A. We discuss the oxygen…
The nature and role of the binary companion of carbon-oxygen white dwarf stars that explode as Type Ia supernovae (SNe Ia) are not yet fully understood. Past detections of circumstellar material (CSM) that contain hydrogen for a small…
It has recently been realized that supernova neutrino signals may be affected by shock propagation over a time interval of a few seconds after bounce. In the standard three-neutrino oscillation scenario, such effects crucially depend on the…
At present, there are strong indications that white dwarf (WD) stars with masses well below the Chandrasekhar limit (MCh ~ 1.4 Msun) contribute a significant fraction of SN Ia progenitors. The relative fraction of stable iron-group elements…
We explore the possible nature of high-velocity features in Type~Ia supernovae by presenting synthetic spectra generated from hydrodynamic models of interaction between the supernova and a compact circumstellar shell. We use TARDIS to…
Standard spectroscopic analyses of Cepheid variables are based on hydrostatic one-dimensional model atmospheres, with convection treated using various formulations of mixing-length theory. This paper aims to carry out an investigation of…
Linking supernovae to their progenitors is a powerful method for furthering our understanding of the physical origin of their observed differences, while at the same time testing stellar evolution theory. In this second study of a series of…
An increase in the number of studied Type Ia supernovae (SNe~Ia) has demonstrated that this class of explosions has a greater diversity in its observables than was previously assumed. The reasons (e.g. the explosion mechanism, progenitor…
We use the new NLTE lightcurve and spectral synthesis code JEKYLL to evolve a macroscopically mixed ejecta model of a type IIb Supernova (SN) originating from a star with an initial mass of 12 solar masses through the photospheric and…
Since the discovery of SN (supernova) 1987A, the number of Type II-peculiar SNe has grown, revealing a rich diversity in photometric and spectroscopic properties. In this study, using a single 15Msun low-metallicity progenitor that dies as…
We simulate time-dependent particle acceleration in the blast wave of a young supernova remnant (SNR), using a Monte Carlo approach for the diffusion and acceleration of the particles, coupled to an MHD code. We calculate the distribution…
Here we revisit line identifications of type I supernovae and highlight trace amounts of unburned hydrogen as an important free parameter for the composition of the progenitor. Most 1-dimensional stripped-envelope models of supernovae…
Stripped-envelope supernovae (SESNe) are a subclass of core-collapse supernovae that are deficient in hydrogen (SN~IIb, SN~Ib) and possibly helium (SN~Ic) in their spectra. Their progenitors are likely stripped of this material through a…
We present the first three-dimensional study of the asymptotic ejecta distributions for a suite of theoretical Type IIp supernovae originating from red supergiant progenitors. We simulate using the radiation-hydrodynamic code F{\sc{ornax}}…