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the theoretical understanding of Type Ia Supernovae

the theoretical understanding of Type Ia Supernovae. Daniel Kasen. SN cosmology. “super-nova”. Supernova Discovery History Asiago Catalog (all supernova types). Proposed. Supernova Factory Lick observatory SN search CfA SN group Carnegie SN project ESSENCE Supernova Legacy Survey.

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the theoretical understanding of Type Ia Supernovae

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  1. the theoretical understanding of Type Ia Supernovae Daniel Kasen

  2. SN cosmology “super-nova” Supernova Discovery HistoryAsiago Catalog (all supernova types)

  3. Proposed Supernova Factory Lick observatory SN search CfA SN group Carnegie SN project ESSENCE Supernova Legacy Survey PanStarrs Dark Energy Survey JDEM Large Synoptic Survey Telescope (LSST) Supernova Discovery FutureRough predictions and promises… Dark Energy Measurements Systematic error, not statistical error, is the issue (e.g., luminosity evolution) Aim for Type Ia SNe as reliable standard candles to a few %

  4. SN Ia ProgenitorsAccreting white dwarf near the Chandrasekhar limit Accretion rate: 10-7 Msun / year

  5. White Dwarf IgnitionKuhlen, Woosley, and Glaitzmeier (2006)

  6. t = 0.0 sec t = 0.5 sec t = 1.0 sec t = 1.5 sec 3D Deflagration ModelSubsonic turbulent flame burning Roepke et al. (2005)

  7. C/O Si/S/Ca 56Ni Fe C/O boom

  8. Type Ia Supernova Light Curvespowered by the beta decay: 56Ni 56Co 56Fe

  9. Type Ia Supernova Spectrum 20 days after explosion

  10. Spectroscopic Homogeneity and Diversitymonitoring silicon expansion velocities from Leonard et al, ApJ 2006

  11. Type Ia Width-Luminosity Relationbrighter supernovae have broader light curves

  12. FeII bound-bound Supernova Ejecta Opacityblending of millions of line transitions FeIII bound-bound

  13. DOE: Scientific Discovery through Advanced Computing (SciDAC) The “Computational Astrophysics Consortium” (CAC) Stan Woosley (PI) UC Santa Cruz, UC Berkeley, Stanford, Arizona, Stony Brook, JHU, LANL, LLNL, LBNL Models Presupernova Evolution (~100-109 years) accreting, convective white dwarf Type Ia supernova theoretical simulation challenge ignition Explosion (~1-100 secs) turbulent nuclear combustion / hydrodynamics free expansion Light Curves / Spectra (~100 days) radioactive decay / radiative transfer Observations

  14. 3-dimensional Time-Dependent Monte Carlo Radiative Transfer SEDONA Code Expanding atmosphere Realistic opacities Three-dimensional Time-dependent Multi-wavelength Includes spectropolarization Includes radioactive decay and gamma-ray transfer Iterative solution for thermal equilibrium Kasen et al 2006 ApJ

  15. Large Scale Computing Incite award, Oak Ridge Lab: 4 million hours/year Atlas “grand challenge” LLNL: 4 million hours/year NERSC award, LBL: 3 million hours/year Jacquard, NERSC

  16. C/O Si/S/Ca 56Ni Fe Grid of Type Ia Supernova Models w/ Stan Woosley Sergei Blinikov Elena Sorokina 130 one-dimensional Chandrasekhar mass models with varied composition Parameters MFe MNi MSi “mixing” MFe +MNi +MSi + Mco = MCH

  17. Broadband Synthetic Light CurvesModel Compared to observations of SN 2001el Parameters MFe = 0.1 Msun MNi = 0.6 Msun MSi = 0.4 Msun Kasen, ApJ 2006 Kasen (2006) ApJ

  18. Day 15 after explosion Time Evolution of SpectrumRecession of photosphere reveals deeper layers Day 35 after explosion C/O Si/S/Ca Model SN1994D 56Ni Fe

  19. Width-Luminosity RelationshipKasen and Woosley, ApJ, 2007 Vary 56Ni production MNi = 0.35 to 0.70 Msun

  20. The Width-Luminosity RelationshipKasen and Woosley, ApJ, 2007 Brighter models are hotter and more ionized and have different opacity behavior Vary 56Ni production

  21. The Width-Luminosity RelationshipKasen and Woosley, ApJ, 2007 Vary silicon production (explosion energy) Vary 56Ni production

  22. Multi-Dimensional ModelsRoepke et al (2005)

  23. 2D Deflagration Model Roepke, Kasen, Woosley MNi = 0.2 Msun EK = 0.3 x 1051 ergs

  24. DeflagrationToDetonationKhokhlov (1991)Hoeflich (1994)Gamezo et al (2005) Gamezo et al. But how to detonate?

  25. 2D Delayed Detonation Roepke, Kasen, Woosley Earlier Detonation (higher densities) gives more 56Ni production MNi = 0.5 Msun EK = 1.2 x 1051 ergs

  26. Off-Center Ignition University of Chicago FLASH Center

  27. Detonation From Failed DeflagrationPlewa, ApJ (2007) Is the transition robust in 3-dimensional calculations?

  28. Off-center ExplosionPlewa (2007) Kasen and Plewa (2007)

  29. Asymmetry and SN Ia DiversityMaximum Light Spectrum

  30. Asymmetry and SN Ia DiversityB-band Light Curve and the Phillips Relation

  31. The Theoretical Understanding of Type Ia Supernovae Pressing Questions How and where does ignition happen? How might the deflagration transition into a detonation? Can we reproduce the observed spectra and light curves from first principles? How do the light curves depend upon progenitor environment?

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