A5045263387- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Nuclear physics research studies
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Neutrino Physics Research
- Nuclear Physics and Applications
- Astrophysics and Star Formation Studies
- Solar and Space Plasma Dynamics
- Astronomical and nuclear sciences
- Geophysics and Gravity Measurements
- Laser-Plasma Interactions and Diagnostics
- Non-Destructive Testing Techniques
- Cosmology and Gravitation Theories
- Superconducting Materials and Applications
- Computational Fluid Dynamics and Aerodynamics
- Dark Matter and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Galaxies: Formation, Evolution, Phenomena
- Atomic and Subatomic Physics Research
- Planetary Science and Exploration
- Fluid Dynamics and Turbulent Flows
Max Planck Institute for Astrophysics
2015-2025
Technical University of Munich
1994-2023
Excellence Cluster Origins
2023
Max Planck Society
2006-2016
Excellence Cluster Universe
2014
Heidelberg Institute for Theoretical Studies
2011
University of Würzburg
2011
Mount Stromlo Observatory
2007-2011
Max Planck Institute for Extraterrestrial Physics
2011
Los Alamos National Laboratory
2010
▪ Abstract Because calibrated light curves of type Ia supernovae have become a major tool to determine the local expansion rate universe and also its geometrical structure, considerable attention has been given models these events over past couple years. There are good reasons believe that perhaps most explosions white dwarfs approached Chandrasekhar mass, [Formula: see text], disrupted by thermonuclear fusion carbon oxygen. However, mechanism whereby such accreting carbon-oxygen explode...
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 present results for a suite of 14 three-dimensional, high-resolution hydrodynamical simulations delayed-detonation models Type Ia supernova (SN Ia) explosions. This model comprises the first set three-dimensional SN with detailed isotopic yield information. As such, it may serve as data base Chandrasekhar-mass nucleosynthetic yields and deriving synthetic observables such spectra light curves. employ physically motivated, stochastic based on turbulent velocity fluctuations fuel density to...
One of the most important questions regarding progenitor systems Type Ia supernovae (SNe Ia) is whether mergers two white dwarfs can lead to explosions that reproduce observations normal events. Here we present a fully three-dimensional simulation violent merger carbon-oxygen with masses $0.9 \mathrm{M_\odot}$ and $1.1 combining very high resolution exact initial conditions. A well-tested combination codes used study system. We start dynamical inspiral phase follow subsequent thermonuclear...
The explosion of sub-Chandrasekhar mass white dwarfs via the double detonation scenario is a potential explanation for type Ia supernovae. In this scenario, surface in helium layer initiates underlying carbon/oxygen core leading to an explosion. For given mass, lower bound has been determined on shell required dynamical burning during flash, which necessary prerequisite detonation. range and corresponding minimum masses, we investigate whether assumed capable triggering subsequent even...
Type Ia supernovae, the thermonuclear explosions of white dwarf stars composed carbon and oxygen, were instrumental as distance indicators in establishing acceleration universe's expansion. However, physics explosion are debated. Here we report a systematic spectral analysis large sample well-observed type supernovae. Mapping velocity distribution main products nuclear burning, constrain theoretical scenarios. We find that all supernovae have low-velocity cores stable iron-group elements....
Type Ia supernovae are important cosmological distance indicators. Each of these bright supposedly results from the thermonuclear explosion a white dwarf star that, after accreting material companion star, exceeds some mass limit, but true nature progenitor system remains controversial. Here we report spectroscopic detection circumstellar in normal type supernova explosion. The expansion velocities, densities, and dimensions envelope indicate that this was ejected system. In particular,...
Explosions of sub-Chandrasekhar-mass white dwarfs are one alternative to the standard Chandrasekhar-mass model Type Ia supernovae. They interesting since binary systems with primary should be common and this scenario would suggest a simple physical parameter which determines explosion brightness, namely mass exploding dwarf. Here we perform one-dimensional hydrodynamical simulations, associated post-processing nucleosynthesis multi-wavelength radiation transport calculations for pure...
We investigate whether pure deflagration models of Chandrasekhar-mass carbon–oxygen white dwarf stars can account for one or more subclass the observed population Type Ia supernova (SN Ia) explosions. compute a set 3D full-star hydrodynamic explosion models, in which strength is parametrized using multispot ignition approach. For each model, we calculate detailed nucleosynthesis yields post-processing step with 384 nuclide nuclear network. also synthetic observables our Monte Carlo radiative...
The Public European Southern Observatory Spectroscopic Survey of Transient Objects (PESSTO) began as a public spectroscopic survey in April 2012. We describe the data reduction strategy and products which are publicly available through ESO archive Data Release 1 (SSDR1). PESSTO uses New Technology Telescope with EFOSC2 SOFI to provide optical NIR spectroscopy imaging. target supernovae transients brighter than 20.5mag for classification. Science targets then selected follow-up based on...
As part of an on-going effort to identify, understand and correct for astrophysics biases in the standardization Type Ia supernovae (SNIa) cosmology, we have statistically classified a large sample nearby SNeIa into those located predominantly younger or older environments. This classification is based on specific star formation rate measured within projected distance 1kpc from each SN location (LsSFR). important refinement compared using local directly as it provides normalization relative...
Abridged. In the double detonation scenario for Type Ia supernovae (SNe Ia) a initiates in shell of He-rich material accreted from companion star by sub-Chandrasekhar-mass White Dwarf (WD). This drives shock front into carbon-oxygen (C/O) WD that triggers secondary core. The core results complete disruption WD. Earlier studies concluded this has difficulties accounting observed properties SNe since explosion ejecta are surrounded products explosive He burning shell. Recently, it was proposed...
Aims.We present synthetic bolometric and broad-band UBVRI light curves of SNe Ia for four selected 3D deflagration models thermonuclear supernovae.
Type Ia supernovae are believed to be white dwarfs disrupted by a thermonuclear explosion. Here we investigate the scenario in which rather low-mass, carbon-oxygen (C + O) dwarf accumulates helium on its surface sufficient amount for igniting detonation shell before Chandrasekhar mass is reached. In principle, this can happen accreting from non-degenerate companion or merging C O with low-mass one. scenario, thought trigger secondary core. It therefore called “double-detonation...
The nearby supernova SN 2011fe can be observed in unprecedented detail. Therefore, it is an important test case for Type Ia (SN Ia) models, which may bring us closer to understanding the physical nature of these objects. Here, we explore how available and expected future observations used constrain explosion scenarios. We base our discussion on three-dimensional simulations a delayed detonation Chandrasekhar-mass white dwarf violent merger two dwarfs-realizations models appropriate most...
The abundance stratification in the ejecta of normal Type Ia supernova 2002bo is derived by fitting a series spectra obtained at close time intervals. A Monte Carlo code, modified to include stratification, used compute synthetic 13 epochs photospheric phase, starting 13d before B maximum. description distribution above 7600 km/s thus obtained. Abundances deeper layers, down zero velocity, are from models two nebular-phase spectra. Elements synthesized different stages burning significantly,...
We present 32 epochs of optical (3300-9700 \AA) spectrophotometric observations the nearby quintessential "normal" type Ia supernova (SN Ia) SN 2011fe in galaxy M101, extending from -15 to +97 d with respect B-band maximum, obtained by Nearby Supernova Factory collaboration. is closest (\mu = 29.04) and brightest (Bmax 9.94 mag) observed since advent modern large scale programs for intensive periodic followup supernovae. Both synthetic light curve measurements spectral feature analysis...
2002cx-like supernovae are a sub-class of sub-luminous Type Ia (SNe). Their light curves and spectra characterized by distinct features that indicate strong mixing the explosion ejecta. Pure turbulent deflagrations have been shown to produce such mixed Here, we present hydrodynamics, nucleosynthesis radiative-transfer calculations for 3D full-star deflagration Chandrasekhar-mass white dwarf. Our model is able reproduce characteristic observational SN 2005hk (a prototypical supernova), not...
The origin of subluminous Type Ia supernovae (SNe Ia) has long eluded any explanation, as all Chandrasekhar-mass models have severe problems reproducing them. Recently, it been proposed that violent mergers two white dwarfs 0.9 M_sun could lead to SNe events resemble 1991bg-like SNe~Ia. Here we investigate whether this scenario still works for with a mass ratio smaller than one. We aim determine the range ratios which detonation forms during merger, only those will SN Ia. This is an...
We present the results of nucleosynthesis calculations based on multi-dimensional (2D and 3D) hydrodynamical simulations thermonuclear burning phase in type Ia supernovae (hereafter SN Ia). The detailed nucleosynthetic yields our explosion models are calculated by post-processing ejecta, using passively advected tracer particles. nuclear reaction network employed computing explosive contains 383 species, ranging from neutrons, protons, α-particles to 98Mo. Our follow common assumption that...