Related papers: NLTE Effects on Kilonova Expansion Opacities
Based on the medium-high resolution (R~ 20,000), modest signal-to-noise ratio (S/N > 70) FLAMES-GIRAFFE spectra, we investigated the copper abundances of 129 red giant branch stars in the Galactic bulge with [Fe/H] from -1.14 to 0.46 dex.…
Non-local thermodynamic equilibrium (NLTE) line formation for neutral and singly-ionized iron is considered through a range of stellar parameters characteristic of cool stars. A comprehensive model atom for Fe I and Fe II is presented. Our…
When two Neutron Stars collide a multi-band electromagnetic emission, known as Kilonova (KN), follows being powered by the radioactive decay of ejecta products. In this contribution we discuss how the equation of state of dense matter,…
Accurately known stellar lithium abundances may be used to shed light on a variety of astrophysical phenomena such as Big Bang nucleosynthesis, radial migration, ages of stars and stellar clusters, and planet engulfment events. We present a…
Aims. We investigate statistical equilibrium of Cr in the atmospheres of late-type stars to show whether the systematic abundance discrepancy between Cr I and Cr II lines, as often encountered in the literature, is due to deviations from…
We developed a comprehensive model atom of Sc II-Sc III. Abundances of scandium for a sample of eight unevolved A9-B3 type stars with well-determined atmospheric parameters were determined based on the non-local thermodynamic equilibrium…
One of the most promising electromagnetic signatures of compact object mergers are kilonovae: approximately isotropic radioactively-powered transients that peak days to weeks post-merger. Key uncertainties in modeling kilonovae include the…
We investigate the nucleosynthesis and kilonova emission based on numerical-relativity binary neutron star merger simulations that incorporate a two-moment neutrino-transport scheme. Unlike in previous works with simpler neutrino…
Among the various classes of fast optical transients (FOTs), kilonovae (KNe), which can emerge as a result of neutron star mergers, are extremely challenging to observe because of not only the rapid timescale on which they fade (on the…
We develop a method to compute synthetic kilonova light curves that combines numerical relativity simulations of neutron star mergers and the $\texttt{SNEC}$ radiation-hydrodynamics code. We describe our implementation of initial and…
Material expelled from binary neutron star (BNS) mergers can harbor r-process nucleosynthesis and power a Kilonova (KN), both intimately related to the astrophysical conditions of the ejection. In turn such conditions indirectly depend on…
The spectra of singly ionised Strontium and Yttrium (Sr {\sc ii} and Y {\sc ii}) have been proposed as identifications of certain spectral features in the AT2017gfo spectrum. With the growing demand for NLTE simulations of Kilonovae, there…
Compact object mergers can produce a thermal electromagnetic counterpart (a "kilonova") powered by the decay of freshly synthesized radioactive isotopes. The luminosity of kilonova light curves depends on the efficiency with which…
An analysis of the CH molecule in non-local thermodynamic equilibrium (NLTE) is performed for the physical conditions of cool stellar atmospheres typical of red giants (log g = 2.0, Teff = 4500 K) and the Sun. The aim of the present work is…
Neutrinos are copiously emitted by neutron star mergers, due to the high temperatures reached by dense matter during the merger and its aftermath. Neutrinos influence the merger dynamics and shape the properties of the ejecta, including the…
We present a set of nonlocal thermodynamic equilibrium steady-state calculations of radiative transfer for one-year old type II supernovae (SNe) starting from state-of-the-art explosion models computed with detailed nucleosynthesis. This…
NLTE radiative transfer calculations of differentially expanding supernovae atmospheres are computationally intensive and are almost universally performed in time-independent snapshot mode. The validity of the steady-state approximation in…
We present non-Local Thermodynamic Equilibrium (non-LTE) calculations for neutral carbon spectral line formation, carried out for a grid of model atmospheres covering the range of late-type stars. The results of our detailed calculations…
The interpretation of water lines in red supergiant stellar atmospheres has been much debated over the past decade. The introduction of the so-called MOLspheres to account for near-infrared "extra" absorption has been controversial. We…
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…