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Outline Introducing thermonuclear supernovae
Scales: time, space & physics Many sins of turbulent deflagrations Foreplay counts: forgotten tale of the ICs Detonating Failed Deflagrations Confronting DFD with observations Summary November 12, 2018
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What Are Supernovae? November 12, 2018
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Massive and Even More Massive
Type II Massive Single H-rich Type Ia Medium mass Binary H/He-free November 12, 2018
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Type Ia SN Appearance P. Nugent (LBNL) November 12, 2018
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Why Do We Care? SN Ia are crucial for galactic chemical evolution.
COBE SN Ia are crucial for galactic chemical evolution. SN Ia are also crucial for cosmology: probes allowing study of expansion and geometry (M, ) of the Universe, nature of dark energy Provide astrophysical setting for basic combustion problems. High-Z Supernova Search Team, HST November 12, 2018
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40 Years of Theory 1960s WD explosion proposed for Type Ia (Hoyle & Fowler) 1D detonation model (Arnett) 1970s detonation models (several groups) deflagration models (Nomoto) 1980s improved 1-D deflagration models (Nomoto) first 2-D deflagration model (Mueller & Arnett) 1990s 2-D and 3-D deflagration models, DDT (Khokhlov) non-standard models 2-D He detonations (Livne & Arnett) small scale flame turbulence (Niemeyer & Hillebrandt) 2000s 3-D deflagration models (NRL, MPA, Barcelona, Chicago) 3-D DDT models (NRL) November 12, 2018
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Problem Parameters Channels for progenitors Binary evolution
11/12/2018 Problem Parameters Channels for progenitors Binary evolution Population synthesis Initial conditions State of the stellar core Metallicity Rotation profile Magnetic fields Basic physics Flame on intermediate scales Unsteadiness DDT Numerics Multiphysics coupling Nucleosynthesis postprocessing R. Hynes INCITE 2004 F. Timmes Lightcurve image is a Hubble (Wide Field and Planetary Camera 2) image of SN 1997cj. Zhang et al. (2006) Khokhlov (2003) November 12, 2018
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Explosive Stage of SN Ia
102/4-7 cm mild ignition 1010 seconds deeply subsonic, Ma ~ 10-4 10-3/5-8 cm few seconds deflagration subsonic: Ma ~ 0.3 101/5-8 cm detonation 0.5 second compressible: Ma ~ 2 November 12, 2018
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Why Large Scale Simulations?
Khokhlov (2003) November 12, 2018
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RT-driven Turbulence Zhang et al. (2006) November 12, 2018
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Major Sins of Classic Central Deflagrations
1. Uniformly mixed ejecta, unburned low-velocity carbon 2. Explosion energies too low, need ~50% more burning 3. Initial conditions either too idealized or defined ad hoc 4. Large Ni-rich structures visible at maximum light 5. Insufficient production of intermediate mass elements November 12, 2018
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Central Ignition Whole Star Model
INCITE 2004 Two models, 255,000 SUs and 5TB of data per model, 8 km resolution November 12, 2018
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Ejecta Composition: Pure Deflagrations
Ni C/O Si Mg Gamezo et al. (2003) Reinecke et al. (2002) Roepke et al. (2005) Garcia-Senz & Bravo (2004) November 12, 2018
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Stratification, Energy: Speculative DDT
3-D pure deflagration 3-D speculative DDT Gamezo et al. (2003) November 12, 2018
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Initial Conditions November 12, 2018 Garcia-Senz & Woosley (1995)
Hoeflich & Stein (2002) Kuhlen, Woosley, & Glatzmeier (2005) November 12, 2018
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Single Bubble, Three Different Methods…
Livne, Asida, & Hoeflich (2005) 3-D Niemeyer, Hillebrandt, & Woosley (1996) …and virtually the same result! Calder et al. (2004) November 12, 2018
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Initial Conditions: Location, Velocity Field
r1y100v100a3030in (inflowing, 100 km/s) INCITE 2004 November 12, 2018
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the off-center deflagration.
Initial Conditions: Conclusion Garcia-Senz & Woosley (1995) Hoeflich & Stein (2002) Woosley, Wunsch, & Kuhlen (2004) Calder et al. (2004) Livne, Asida, & Hoeflich (2005) Kuehlen, Woosley, & Glatzmeier (2005) Based on analytic, semi-analytic, and numerical models, the most likely outcome of a mild ignition is the off-center deflagration. November 12, 2018
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Detonating Failed Deflagration
November 12, 2018
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DFD Detonation Phase November 12, 2018
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Double-bubble DFD November 12, 2018
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Double-bubble DFD at 1 km resolution
November 12, 2018
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Model Validation – Radiative Transfer
Kasen, Thomas, & Nugent (2006): Multi-dimensional time-dependent Monte Carlo radiative transfer November 12, 2018
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Model Validation – Radiative Transfer
Kasen, Thomas, & Nugent (2006): Multi-dimensional time-dependent Monte Carlo radiative transfer November 12, 2018
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Overall Spectrum Shape
DFD at 18 days vs. SN1981B at maximum light. November 12, 2018
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DFD/W7 At Maximum Light November 12, 2018
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Velocity Evolution Orientation effects controlled by the deflagration
phase in the DFD model Benetti et al. (2005) November 12, 2018
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Distribution of IME in DFD
November 12, 2018
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GCD Spectral Signatures
Kasen & Plewa (2005) November 12, 2018
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Tycho SNR Iron Distribution
FS RS ??? Warren et al. (2005) November 12, 2018
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Summary To be continued! Detonating Failed Deflagration
displays several main characteristics of observed objects energetics, light curves, spectra/spectral features emphasized importance of the initial conditions detonation in unconfined environment natural chain of events, not by-hand, but from first principles Extremely rare case in theoretical astrophysics! To be continued! November 12, 2018
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