Supernova theory, numerical and analytic, has made remarkable progress in the past decade. This was possible by more sophisticated simulation tools, especially for neutrino transport, improved microphysics, deeper insights into role of hydrodynamic instabilities. Violent, large-scale nonradial mass motions are generic supernova cores. The neutrino-heating mechanism, aided flows, drives explosions, albeit low-energy ones, ONeMg-core some Fe-core progenitors. characteristics emission from...

ABSTRACT Nucleosynthesis, light curves, explosion energies, and remnant masses are calculated for a grid of supernovae (SNe) resulting from massive stars with solar metallicity 9.0 to 120 <?CDATA ${M}_{\odot }$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mo>⊙</mml:mo> </mml:msub> </mml:math> . The full evolution is followed using an adaptive reaction network up 2000 nuclei. A novel aspect the survey...

Abstract We introduce a new, powerful method to constrain properties of neutron stars (NSs). show that the total mass GW170817 provides reliable constraint on stellar radius if merger did not result in prompt collapse as suggested by interpretation associated electromagnetic emission. The nonrotating NSs with 1.6 can be constrained larger than km, and R max maximum-mass configuration must km. point out detections future events will further improve these constraints. Moreover, we event...

The neutrino flux and spectra formation in a supernova core is studied by using Monte Carlo code. dominant opacity contribution for νμ elastic scattering on nucleons νμN → Nνμ, where always stands either or ντ. In addition, we switch off variety of processes that allow the exchange energy creation destruction pairs, notably nucleon bremsstrahlung NN NNνμμ, pair annihilation e+e- νμμ νee νμμ, recoil weak magnetism scattering, electrons νμe± e±νμ, electron neutrinos antineutrinos νμνe νeνμ νμe...

Abstract Double neutron star (DNS) systems represent extreme physical objects and the endpoint of an exotic journey stellar evolution binary interactions. Large numbers DNS their mergers are anticipated to be discovered using Square Kilometre Array searching for radio pulsars, high-frequency gravitational wave detectors (LIGO/VIRGO), respectively. Here we discuss all key properties systems, as well selection effects, combine latest observational data with new theoretical progress on various...

We present the first comprehensive study of r-process element nucleosynthesis in ejecta compact binary mergers (CBMs) and their relic black-hole (BH)-torus systems. The evolution BH-accretion tori is simulated for seconds with a Newtonian hydrodynamics code including viscosity effects, pseudo-Newtonian gravity rotating BHs, an energy-dependent two-moment closure scheme transport electron neutrinos antineutrinos. investigated cases are guided by relativistic double neutron star (NS-NS) NS-BH...

We present results of simulations stellar collapse and explosions in spherical symmetry for progenitor stars the 8-10 solar mass range with an O-Ne-Mg core. The were continued until nearly one second after core bounce performed Prometheus/Vertex code a variable Eddington factor solver neutrino transport, including state-of-the-art treatment neutrino-matter interactions. Particular effort was made to implement nuclear burning electron capture rates sufficient accuracy ensure smooth...

We perform hydrodynamic supernova (SN) simulations in spherical symmetry for over 100 single stars of solar metallicity to explore the progenitor-explosion and progenitor-remnant connections established by neutrino-driven mechanism. use an approximative treatment neutrino transport replace high-density interior neutron star (NS) inner boundary condition based on analytic proto-NS core-cooling model, whose free parameters are chosen such that explosion energy, nickel production, energy...

An 8.8M{⊙} electron-capture supernova was simulated in spherical symmetry consistently from collapse through explosion to essentially complete deleptonization of the forming neutron star. The evolution time (∼9 s) is short because high-density effects suppress our neutrino opacities. After a phase accretion-enhanced luminosities (∼200 ms), luminosity equipartition among all species becomes almost perfect and spectra ν{e} ν{μ,τ} very similar, ruling out neutrino-driven wind as r-process site....

Thus far, judging the fate of a massive star (either neutron (NS) or black hole) solely by its structure prior to core collapse has been ambiguous. Our work and previous attempts find non-monotonic variation successful failed supernovae with zero-age main-sequence mass, for which no single structural parameter can serve as good predictive measure. However, we identify two parameters computed from pre-collapse progenitor, in combination allow clear separation exploding non-exploding cases...

We demonstrate by a large set of merger simulations for symmetric binary neutron stars (NSs) that there is tight correlation between the frequency peak postmerger gravitational-wave (GW) emission and physical properties nuclear equation state (EoS), e.g. expressed radius maximum-mass Tolman-Oppenheimer-Volkhoff configuration. Therefore, single measurement GW signal will constrain NS EoS significantly. For plausible optimistic merger-rate estimates corresponding detection with Advanced LIGO...

We present two-dimensional hydrodynamic simulations of stellar core collapse and develop the framework for a detailed analysis energetic aspects neutrino-powered supernova explosions. Our results confirm that neutrino-heating mechanism remains viable explanation explosion wider mass range progenitors with iron cores, but sets in later develops differently than thought so far. The calculations were performed an energy-dependent treatment neutrino transport based on "ray-by-ray plus"...

We investigate systematically the dynamical mass ejection, r-process nucleosynthesis, and properties of electromagnetic counterparts neutron-star (NS) mergers in dependence on uncertain nuclear equation state (EoS) by employing 40 representative, microphysical high-density EoSs relativistic, hydrodynamical simulations. The crucial parameter determining ejecta is radius R_1.35 a 1.35 M_sun NS. NSs with smaller ("soft" EoS) eject higher masses. These range from ~10^-3 to ~10^-2 for 1.35-1.35...

We present a detailed theoretical analysis of the gravitational-wave (GW) signal post-bounce evolution core-collapse supernovae (SNe), employing for first time relativistic, two-dimensional (2D) explosion models with multi-group, three-flavor neutrino transport based on ray-by-ray-plus approximation. The waveforms reflect accelerated mass motions associated characteristic evolutionary stages that were also identified in previous works: A quasi-periodic modulation by prompt postshock...

We perform hydrodynamical simulations of neutron-star mergers for a large sample temperature-dependent, nuclear equations state, and determine the threshold mass above which merger remnant promptly collapses to form black hole. find that, depending on equation is larger than maximum non-rotating star in isolation by between 30 70 per cent. Our also show that ratio tightly correlated with compactness maximum-mass configuration. speculate how this relation can be used derive constraints...

We present 3D simulations of supernova (SN) explosions nonrotating stars, triggered by the neutrino-heating mechanism with a suitable choice core-neutrino luminosity. Our results show that asymmetric mass ejection caused hydrodynamic instabilities can accelerate neutron star (NS) up to recoil velocities more than 700 km/s "gravitational tug-boat mechanism", which is enough explain most observed pulsar velocities. The associated NS spin periods are about 100 ms 8 s without any correlation...

Nonspherical mass motions are a generic feature of core-collapse supernovae, and hydrodynamic instabilities play crucial role in the explosion mechanism. The first successful neutrino-driven explosions could be obtained with self-consistent, first-principles simulations three spatial dimensions. But three-dimensional (3D) models tend to less prone than corresponding axisymmetric two-dimensional (2D) ones. reason is that 3D turbulence leads energy cascading from large small scales, inverse 2D...

Neutron-star (NS) merger simulations are conducted for 38 representative microphysical descriptions of high-density matter in order to explore the equation-of-state dependence postmerger ring-down phase. The formation a deformed, oscillating, differentially rotating very massive NS is typical outcome coalescence two stars with 1.35 $M_{\odot}$ most candidate EoSs. oscillations this object imprint pronounced peak gravitational-wave (GW) spectra, which used characterize emission given model....

Interactions with neutrons and protons play a crucial role for the neutrino opacity of matter in supernova core. Their current implementation many simulation codes, however, is rather schematic ignores not only modifications correlated nuclear medium nascent neutron star, but also free-space corrections from nucleon recoil, weak magnetism, or strange quarks, which can easily add up to changes several 10% energies spectral peak. In Garching simulations Prometheus-Vertex code, such...

We study the impact of large-scale perturbations from convective shell burning on core-collapse supernova explosion mechanism using three-dimensional (3D) multi-group neutrino hydrodynamics simulations an 18 solar mass progenitor. Seed asphericities in O shell, obtained a recent 3D model burning, help trigger neutrino-driven 330ms after bounce whereas shock is not revived based spherically symmetric progenitor for at least another 300ms. tentatively infer reduction critical luminosity...

We present the first successful simulation of a neutrino-driven supernova explosion in three dimensions (3D), using Prometheus-Vertex code with an axis-free Yin–Yang grid and sophisticated treatment three-flavor, energy-dependent neutrino transport. The progenitor is nonrotating, zero-metallicity 9.6 star iron core. While spherical symmetry outward shock acceleration sets later than 300 ms after bounce, starts at ∼130 postbounce two (2D). 3D model explodes about same time but faster...

The relevance of the standing accretion shock instability (SASI) compared to neutrino-driven convection in three-dimensional (3D) supernova-core environments is still highly controversial. Studying a 27 Msun progenitor, we demonstrate, for first time, that violent SASI activity can develop 3D simulations with detailed neutrino transport despite presence convection. This result was obtained Prometheus-Vertex code same sophisticated treatment so far used only 1D and 2D models. While buoyant...

Since core-collapse supernova simulations still struggle to produce robust neutrino-driven explosions in 3D, it has been proposed that asphericities caused by convection the progenitor might facilitate shock revival boosting activity of non-radial hydrodynamic instabilities post-shock region. We investigate this scenario depth using 42 relativistic 2D with multi-group neutrino transport examine effects velocity and density perturbations for different perturbation geometries obey fundamental...