Related papers: Time-dependent 3D spectrum synthesis for type Ia s…
In the nebular phase, supernovae are powered by radioactive decay and continuously fade, while their densities have decreased enough such that the expanding nebula becomes (largely) optically thin and the entire structure contributes to the…
We present a study of the morphology of the ejecta in Supernova 1987A based on images and spectra from the HST as well as integral field spectroscopy from VLT/SINFONI. The HST observations were obtained between 1994 - 2011 and primarily…
Near-infrared spectra of the subluminous Type Ia SN1999by are presented which cover the time evolution from about 4 days before to 2 weeks after maximum. Analysis of these data was accomplished through the construction of an extended set of…
It is found that the total IMF-transverse-energy (E_t) spectra in multi-IMF events are well represented by synthetic spectra obtained by folding of the single-IMF spectrum. Using the experimental IMF multiplicity distribution, the observed…
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…
The finite time, $\tau_{\rm dep}$, over which positrons from $\beta^{+}$ decays of $^{56}$Co deposit energy in type Ia supernovae ejecta lead, in case the positrons are trapped, to a slower decay of the bolometric luminosity compared to an…
Observations of type II supernova early light, from breakout until recombination, can be used to constrain the explosion energy and progenitor properties. Currently available for this purpose are purely analytic models, which are accurate…
Spectra of late-type stars are usually analyzed with static model atmospheres in local thermodynamic equilibrium (LTE) and a homogeneous plane-parallel or spherically symmetric geometry. The energy balance requires particular attention, as…
In this paper, we review the present state of theoretical models of thermonuclear supernovae, and compare their predicitions with the constraints derived from observations of Type Ia supernovae. The diversity of explosion mechanisms usually…
We solve the radiative transfer equation (RTE) in anisotropically scattering media as an infinite series. Each series term represents a distinct number of scattering events, with analytical solutions derived for zero and single scattering.…
We investigate a simplified kinetic system of the hydrogen atom (two levels plus continuum) under conditions of a type IIP supernova at the plateau phase that realistically describes the basic properties of the complete system. We have…
We extend our time-dependent hydrogen ionization simulations of diffuse ionized gas to include metals important for collisional cooling and diagnostic emission lines. The combination of heating from supernovae and time-dependent collisional…
A study of the time sequence of optical colours of a large sample of nearby Type Ia supernovae (SNe Ia) is presented. We study the dependence of the colour time evolution with respect to the lightcurve shape, parametrized by the stretch…
We present direct spectroscopic modeling of five Type Iax supernovae (SNe) with the one dimensional Monte Carlo radiative transfer code TARDIS. The abundance tomography technique is used to map the chemical structure and physical properties…
(Abridged) We describe a new algorithm for solving the coupled frequency-integrated transfer equation and the equations of magnetohydrodynamics when the light-crossing time is only marginally shorter than dynamical timescales. The transfer…
Several explosions of thermonuclear supernovae (SNe Ia) have been found to exhibit deviations from spherical symmetry upon closer inspection. Examples are the gamma-ray lines from SN 2014J as measured by INTEGRAL/SPI, and morphology…
Twenty years after the explosion of SN 1987A, we are now able to observe the three-dimensional spatially resolved inner ejecta. Detailed mapping of newly synthesised material and its radioactive decay daughter products sheds light on the…
Aims. We present the first theoretical SN Ia light curves calculated with the time-dependent version of the general purpose model atmosphere code PHOENIX. Our goal is to produce light curves and spectra of hydro models of all types of…
We present the results of two-dimensional radiation-hydrodynamic simulations of expanding supernova ejecta with a central energy source. As suggested in previous multi-dimensional hydrodynamic simulations, a sufficiently powerful central…
(abridged) Models of many astrophysical gamma-ray sources assume they contain a homogeneous distribution of electrons that are injected as a power-law in energy and evolve by interacting with radiation fields, magnetic fields and particles…