Local and Global Radiation Hydrodynamics Simulations of Massive Star Envelopes

Talk given at "The Progenitor-Supernova-Remnant-Connection" conference at Ringberg Castle (Germany). For more info on the conference: http://wwwmpa.mpa-garching.mpg.de/conf/psrc/ For more info on the crazy history of the Ringberg Castle: http://girlandkat.com/blog/2013/7/3/f226nxlbn28jtx3rvqpkf302n2xyqo

Transcript

1. Local and Global Radiation Hydrodynamics Simulations of Massive Star Envelopes Matteo Cantiello (CCA, Flatiron Institute & Princeton University) Collaborators: Yan-Fei Jiang (ভᆱᷢ), Lars Bildsten, Eliot Quataert, Omer Blaes Image: J. Insley (ALCF) and Y. Jiang (KITP)
2. ! Transient surveys unraveling unpredicted variety of explosive stellar deaths (e.g. PTF/ZTF, ASAS- SN, Pan-STARRS and soon LSST). We do not understand SN progenitors ! We are entering the era of high precision stellar physics (Kepler, BRITE, K2, GAIA, TESS, PLATO). Theory is lagging behind ! Dawn of GW-Astronomy Exciting times for Stellar Physics
3. !Stability and energy transport !Mass loss (See e.g. J. Vink & E. Beasor’s Talk) !Rotation !Magnetic Fields !Binarity (Talks from Van Dyk, Hirai, Zapartas, Schneider…) Massive Stars Evolution: The most uncertain physics
4. To Understand CCSNe, GRBs and LIGO GW sources we need to understand the structure, mass loss and binary interactions in massive stars
5. Stability and energy transport Jiang, MC et al. 2015, 2017 Q: How is the energy transported in massive stars envelopes? (Impact on radii and stability) MLT is not supposed to work! Radii Important to understand SN light curves See e.g. Lars Bildsten’s Talk
6. Massive Star Envelopes ! Massive stars can develop radiation dominated, loosely bound envelopes e.g Joss et al. 1973, Paxton et al. 2013 ! In 1D models such envelopes are characterized by: ! Superadiabatic Convection ! Density Inversions (e.g. Grafener et al. 2012) ! Gas Pressure Inversions ! Envelope Inflation (e.g. Sanyal et al. 2015) ! What about 3D?
7. Different regimes in Radiation Dominated Convection Diff Rad Flux Advection Flux (“convection”…) Critical optical depth Optical depth where radiation diffusion timescale = dynamical timescale MLT is not supposed to work!
8. Stability and energy transport Jiang, MC et al. 2015, 2017 1D Stellar Evolution ( ) 3D Local Radiation MHD (ATHENA) 3D Global Radiation MHD (ATHENA++)
9. The Opacity: Iron Peak 7.0 5.0 5.5 6.0 6.5 7.0 log T 0.0 0.5 1.0 1.5 2.0 k (cm2 g 1) 60 M ZAMS profiles Z=0.02 Z=0.01 Z=0.004 Z=0.001 Z=0.0001 Fe Paxton, MC et al. 2015 Cantiello et al. 2009 Iglesias & Rogers 1996 Strong Metallicity Dependence
10. The Opacity: Iron Peak At fixed density around Iron Opacity peak. Neighboring lines: x10 in rho Fe Jiang, MC et al. 2015
11. 3D Radiation Hydro Calculations: Energy Transport & Stability
12. Simulations Setup ATHENA with VET Radiation Module Jiang, MC et al. 2015 Jiang et al. 2014 Davis et al. 2014
13. Initial Conditions Guided from MESA 1D models StarTop StarDeep StarMid Jiang, MC et al. 2015
14. Initial Conditions Guided from MESA 1D models StarTop StarDeep StarMid Jiang, MC et al. 2015 Efficient Convection Inefficient Convection
15. Jiang, MC et al. 2015 STARTOP The case with inefficient convection
16. STARTOP The case with inefficient convection Superadiabaticity Jiang, MC et al. 2015
17. The Porosity Factor Density weighted radiation acceleration See e.g. Owocki et al. 2004 Jiang, MC et al. 2015
18. Density Inversion still present (in average) Porosity reduces radiative acceleration, but not enough to make it sub-Eddington (volume averaged) (density weighted) STARTOP The case with inefficient convection Jiang, MC et al. 2015
19. 3D -> 1D
20. Preliminary 1D implementation ! Use calibrated alpha MLT (using the advection flux calculated in ATHENA) ! Include Porosity Factor (Calibrated from ATHENA calculations) The Porosity Factor: Larger in the presence of B-fields (0.6-1.0) Cantiello, Jiang et al. (in Prep) Jiang, MC et al. 2017
21. Cantiello, Jiang et al. (in Prep) Preliminary Results (no B-fields)
22. 3D Radiation Hydro Calculations: Global Calculations and Mass Loss
23. Initial Conditions Jiang, MC et al. In Prep. Jiang, MC et al. 2015,2017, in Prep
24. Initial Conditions Jiang, MC et al. In Prep. Jiang, MC et al. 2015,2017, in Prep
25. Initial Conditions Jiang, MC et al. In Prep. Jiang, MC et al. 2015,2017, in Prep
26. Initial Conditions Jiang, MC et al. In Prep. Jiang, MC et al. 2015,2017, in Prep
27. Global 3D Athena++, Radiation Hydro Jiang, MC et al. In Prep Preliminary Results!
28. 1.2 1.4 1.6 1.8 2.0 2.2 2.4 log(r/r ) StarMid4c 1.2 1.4 1.6 1.8 2.0 2.2 2.4 log(r/r ) 0 50 100 150 t/t0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 log(r/r ) 10 4 10 3 10 2 10 1 100 101 102 103 104 ⇢/⇢0 10 4 10 3 10 2 10 1 100 101 102 103 Er /ar T 4 0 100 101 102 /0 Jiang, MC et al. In Prep
29. At lower temperatures / later evolutionary phases, things might get even more wild! H
30. Initial Conditions Jiang, MC et al. In Prep. Jiang, MC et al. 2015,2017, in Prep
31. Jiang, MC et al. In Prep Preliminary Results! “Global Cool” 3D Athena++, Radiation Hydro
32. Jiang, MC et al. In Prep
33. Summary 1. Density inversions observed in 1D codes unstable in 3D 2. Porosity of density fluctuations reduce the effective radiation acceleration, but density inversions can persist in a time-averaged sense 3. Realistic stellar structures require implementing the porosity factor and calibrating MLT to the values observed in the 3D calculations 4. First 3D global radiation hydro calculations used to study the stability and mass loss of very luminous stars
34. What’s Next? 1. Effects of magnetic fields (Jiang et al. 2017) 2. 3D->1D To improve predictions of massive star evolution 3. Continuum driven winds / Eruptions ? 4. Effects on line-driven winds (e.g. clumping) Image: J. Insley (ALCF) and Y. Jiang (KITP)