Using Adaptive Nested Mesh Code HydroBox3D for Numerical Simulation of Type Ia Supernovae: Merger of Carbon-Oxygen White Dwarf Stars, Collapse, and Non-Central Explosion

2018 ◽  
Author(s):  
Igor Kulikov ◽  
Igor Chernykh ◽  
Dmitry Karavaev ◽  
Victor Protasov ◽  
Alexander Serenko ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
White Dwarf ◽  
Type Ia Supernovae ◽  
Dwarf Stars ◽  
White Dwarf Stars ◽  
Type Ia ◽  
Ia Supernovae ◽  
Central Explosion

scholarly journals Type Ia Supernovae and Planets in Star Clusters

2003 ◽  
Vol 208 ◽  
pp. 53-60
Author(s):  
Michael M. Shara ◽  
Jarrod R. Hurley
Keyword(s):  
White Dwarf ◽  
Star Clusters ◽  
Mass Function ◽  
Initial Mass Function ◽  
Type Ia Supernovae ◽  
Radiation Emission ◽  
White Dwarf Stars ◽  
Short Period ◽  
Type Ia ◽  
Ia Supernovae

Star clusters are remarkably efficient (relative to the field) at making type Ia supernovae candidates: very short period, massive double-white-dwarf stars and giant-white dwarf binaries. The high frequency of these systems is the result of dynamical encounters between (mostly) primordial binaries and other cluster stars. Orbital hardening rapidly drives the degenerate binaries to periods under ∼ 10 hours. Gravitational radiation emission and mergers then produce supra-Chandrasekhar objects in less than a Hubble time.We also find that free-floating planets can remain bound to a star cluster for much longer than was previously assumed: of the order of the cluster half-mass relaxation timescale as opposed to the crossing-time. The planets in our N-body study are of Jupiter mass and are initially placed in circular orbits of between 0.05 and 50 AU about a parent star whose mass is chosen from a realistic initial mass function. This result is important in the context of the preliminary detection of a population of free-floating sub-stellar objects in the globular cluster M22.

scholarly journals A unified mechanism for unconfined deflagration-to-detonation transition in terrestrial chemical systems and type Ia supernovae

Science ◽  
2019 ◽  
Vol 366 (6465) ◽  
pp. eaau7365 ◽  
Author(s):  
Alexei Y. Poludnenko ◽  
Jessica Chambers ◽  
Kareem Ahmed ◽  
Vadim N. Gamezo ◽  
Brian D. Taylor
Keyword(s):  
Theoretical Models ◽  
Type Ia Supernovae ◽  
Dwarf Stars ◽  
Chemical Systems ◽  
White Dwarf Stars ◽  
Deflagration To Detonation Transition ◽  
Type Ia ◽  
Detonation Transition ◽  
Ia Supernovae ◽  
Open Question

The nature of type Ia supernovae (SNIa)—thermonuclear explosions of white dwarf stars—is an open question in astrophysics. Virtually all existing theoretical models of normal, bright SNIa require the explosion to produce a detonation in order to consume all of stellar material, but the mechanism for the deflagration-to-detonation transition (DDT) remains unclear. We present a unified theory of turbulence-induced DDT that describes the mechanism and conditions for initiating detonation both in unconfined chemical and thermonuclear explosions. The model is validated by using experiments with chemical flames and numerical simulations of thermonuclear flames. We use the developed theory to determine criteria for detonation initiation in the single-degenerate Chandrasekhar-mass SNIa model and show that DDT is almost inevitable at densities of 107 to 108 grams per cubic centimeter.

scholarly journals Precise astronomical flux calibration and its impact on studying the nature of the dark energy

2015 ◽  
Vol 30 (40) ◽  
pp. 1530030 ◽  
Author(s):  
Christopher W. Stubbs ◽  
Yorke J. Brown
Keyword(s):  
Dark Energy ◽  
Survey Methodology ◽  
Atmospheric Transmission ◽  
Dwarf Stars ◽  
White Dwarf Stars ◽  
Accelerating Expansion ◽  
Systematic Uncertainties ◽  
Type Ia ◽  
Ia Supernovae ◽  
Flux Calibration

Measurements of the luminosity of Type Ia supernovae versus redshift provided the original evidence for the accelerating expansion of the Universe and the existence of dark energy. Despite substantial improvements in survey methodology, systematic uncertainty in flux calibration dominates the error budget for this technique, exceeding both statistics and other systematic uncertainties. Consequently, any further collection of Type Ia supernova data will fail to refine the constraints on the nature of dark energy unless we also improve the state of the art in astronomical flux calibration to the order of 1%. We describe how these systematic errors arise from calibration of instrumental sensitivity, atmospheric transmission and Galactic extinction, and discuss ongoing efforts to meet the 1% precision challenge using white dwarf stars as celestial standards, exquisitely calibrated detectors as fundamental metrologic standards, and real-time atmospheric monitoring.

scholarly journals Are the Precursors of Type Ia Supernovae Double Degenerate Mergers?

2004 ◽  
Vol 194 ◽  
pp. 111-112
Author(s):  
Lilia Ferrario
Keyword(s):  
Neutron Stars ◽  
White Dwarf ◽  
White Dwarfs ◽  
Observational Evidence ◽  
Type Ia Supernovae ◽  
Type Ia ◽  
Ia Supernovae

AbstractI argue that the observational evidence for white dwarf-white dwarf mergers supports the view that they give rise to ultra-massive white dwarfs or neutron stars through accretion induced collapse. The implications for the progenitors of Type Ia SNe are discussed.

scholarly journals Symbiotic Stars as Possible Progenitors of SNe Ia: Binary Parameters and Overall Outlook

2011 ◽  
Vol 7 (S281) ◽  
pp. 162-165 ◽  
Author(s):  
J. Mikołajewska
Keyword(s):  
White Dwarf ◽  
Physical Characteristics ◽  
Type Ia Supernovae ◽  
Symbiotic Stars ◽  
Type Ia ◽  
Red Giant ◽  
Ia Supernovae

AbstractSymbiotic stars are interacting binaries in which the first-formed white dwarf accretes and burns material from a red giant companion. This paper aims at presenting physical characteristics of these objects and discussing their possible link with progenitors of Type Ia supernovae.

scholarly journals Type IA Supernovae

1992 ◽  
Vol 151 ◽  
pp. 225-234
Author(s):  
J. Craig Wheeler
Keyword(s):  
White Dwarf ◽  
Cataclysmic Variables ◽  
Type Ia Supernovae ◽  
Low Velocity ◽  
Severe Problem ◽  
Transfer Rates ◽  
Secular Evolution ◽  
Thermonuclear Explosion ◽  
Type Ia ◽  
Ia Supernovae

Spectral calculations show that a model based on the thermonuclear explosion of a degenerate carbon/oxygen white dwarf provides excellent agreement with observations of Type Ia supernovae. Identification of suitable evolutionary progenitors remains a severe problem. General problems with estimation of supernova rates are outlined and the origin of Type Ia supernovae from double degenerate systems are discussed in the context of new rates of explosion per H band luminosity, the lack of observed candidates, and the likely presence of H in the vicinity of some SN Ia events. Re-examination of the problems of triggering Type Ia by accretion of hydrogen from a companion shows that there may be an avenue involving cataclysmic variables, especially if extreme hibernation occurs. Novae may channel accreting white dwarfs to a unique locus in accretion rate/mass space. Systems that undergo secular evolution to higher mass transfer rates could lead to just the conditions necessary for a Type Ia explosion. Tests involving fluorescence or absorption in a surrounding circumstellar medium and the detection of hydrogen stripped from a companion, which should appear at low velocity inside the white dwarf ejecta, are suggested. Possible observational confirmation of the former is described.

scholarly journals Effects of Rotation on Helium Accreting White Dwarf

2004 ◽  
Vol 215 ◽  
pp. 571-572 ◽  
Author(s):  
S.-C. Yoon ◽  
N. Langer
Keyword(s):  
Angular Momentum ◽  
White Dwarf ◽  
Spherical Symmetry ◽  
Binary Systems ◽  
Close Binary ◽  
Type Ia Supernovae ◽  
Classical Studies ◽  
Type Ia ◽  
Effects Of Rotation ◽  
Ia Supernovae

Classical studies of accreting white dwarfs have assumed spherical symmetry. However, it is believed that in close binary systems the transfered matter carries angular momentum to spin up the accreting star. Here, we present preliminary results of CO white dwarf models which accrete helium rich matter with effects of rotation considered, in the context of the Sub-Chandrasekhar mass scenario for Type Ia supernovae.

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