Modeling hyperenergetic and superluminous supernovae Philipp Mösta Einstein fellow @ UC Berkeley [email protected] Roland Haas, Goni Halevi, Christian Ott, Sherwood Richers, Luke Roberts, Erik Schnetter BlueWaters symposium 2017 May 17, 2017 Astrophysics of core-collapse supernovae M82/Chandra/NASA ~ Galaxy evolution/feedback Heavy element nucleosynthesis Birth sites of black holes / neutron stars 2 Neutrinos New era of transient science • Current (PTF, DeCAM, ASAS-SN) and upcoming wide-field time domain astronomy (ZTF, LSST, …) -> wealth of data • adv LIGO / gravitational waves detected • Computational tools at dawn of new exascale era Image: PTF/ZTF/COO Image: LSST 3 New era of transient science • Current (PTF, DeCAM, ASAS-SN) and upcoming wide-field time domain astronomy (ZTF, LSST, …) -> wealth of data • adv LIGO / gravitational waves detected • Computational tools at dawn of new exascale era Transformative years ahead for our understanding of these events Image: PTF/ZTF/COO Image: LSST 4 Hypernovae & GRBs • 11 long GRB – core-collapse supernova associations. • All GRB-SNe are stripped envelope, show outflows v~0.1c • But not all stripped-envelope supernovae come with GRBs • Trace low metallicity and low redshift Neutrino mechanism is inefficient; can’t deliver a hypernova 5 Superluminous supernovae Some events: stripped envelope no interaction 45 Elum ~ 10 erg 52 Erad up to 10 erg Gal-Yam+12 6 Superluminous / hyperenergetic supernovae SLSN Ic lGRBs SN Ic-bl Common engine? 7 Core collapse basics Iron core Protoneutron star r~30km Nuclear equation of state 2000km stiffens at nuclear density Inner core (~0.5 M ) -> protoneutron star + shockwave 8 Core collapse basics Iron core Protoneutron star r~30km Nuclear equation of state 2000km stiffens at nuclear density Inner core (~0.5 M ) -> protoneutron star + shockwave Reviews: Bethe’90 Janka+‘12 L⌫ Outer core accretes onto shock & protoneutron accretion star with O(1) M /s shock Shock stalls at ~ 100 km 9 Core collapse basics Iron core Protoneutron star r~30km Nuclear equation of state 2000km stiffens at nuclear density Inner core (~0.5 M ) -> protoneutron star + shockwave Reviews: Bethe’90 Janka+‘12 L⌫ Core-collapse accretion supernova problem: shock How to revive the shockwave? 10 Magnetorotational mechanism [LeBlanc & Wilson ‘70, Bisnovatyi-Kogan ’70, Obergaulinger+’06, Burrows+ ‘07, Takiwaki & Kotake ‘11, Winteler+ 12] Rapid Rotation + B-field amplification (need magnetorotational instability [MRI]; difficult to resolve, but see, e.g, Obergaulinger+’09, PM+15) 2D: Energetic bipolar explosions Energy in rotation up to 1052 erg Results in ms-period proto-magnetar 11 Burrows+’07 A multiphysics challenge Magneto-Hydrodynamics Gas/plasma dynamics 12 A multiphysics challenge Magneto-Hydrodynamics Gas/plasma dynamics General Relativity Gravity 13 A multiphysics challenge Magneto-Hydrodynamics Gas/plasma dynamics General Relativity Gravity Nuclear EOS, nuclear Nuclear and Neutrino Physics reactions & ν interactions 14 A multiphysics challenge Magneto-Hydrodynamics Gas/plasma dynamics General Relativity Gravity Nuclear EOS, nuclear Nuclear and Neutrino Physics reactions & ν interactions Boltzmann Transport Theory Neutrino transport 15 A multiphysics challenge Magneto-Hydrodynamics Gas/plasma dynamics General Relativity Gravity Nuclear EOS, nuclear Nuclear and Neutrino Physics reactions & ν interactions Fully coupled! Boltzmann Transport Theory Neutrino transport All four forces! 16 A multiphysics challenge Magneto-Hydrodynamics Gas/plasma dynamics General Relativity Gravity Nuclear EOS, nuclear Nuclear and Neutrino Physics reactions & ν interactions Fully coupled! Boltzmann Transport Theory Neutrino transport All four forces! Additional Complication: Core-Collapse Supernovae are 3D • rotation • fluid and MHD instabilities, multi-D structure, spatial scales Need 21st century tools: • cutting edge numerical algorithms • sophisticated open-source software infrastructure • peta/exa scale computers 17 http://einsteintoolkit.org 18 3D Volume Visualization of Entropy PM, Richers+ 14 19 How do we form magnetars? Magnetorotational Mechanism Big uncertainty so far: How do we get the magnetic field amplification? 21 Burrows+’07 First global 3D MHD turbulence simulations • 10 billion grid points (Millenium simulation used 10 billion particles) • 130 thousand cores on Blue Waters • 2 weeks wall time • 60 million compute hours • 10000 more expensive than any previous simulations Does the MRI efficiently build up PM+ 15 Nature dynamically relevant global field? 22 3D magnetic field structure dx=500m dx=200m dx=100m dx=50m 23 PM+ 15 Nature 24 PM+ 15 Nature Growth at Large Scales 7 ( 2.05 + 0.75 ms 1 (t t )) 1033 − − · − map · 32 (t t )/t 6 5 10 e − map , t = 3.5 ms k ·= 4 ] 5 k = 6 erg k = 8 33 4 k = 10 10 )[ k = 20 t ( 3 k = 50 k = 100 ,mag k 2 E 1 0 5 10 t t [ms] − map saturation within 60ms 25 PM+ 15 Nature Global Field Structure PM+ 15 Nature dx=500m dx=50m t=0ms t=10ms t=10ms 26 PM+ 15 Nature Global Field Structure PM+ 15 Nature dx=500m dx=50m Magnetar formation? t=0ms t=10ms t=10ms 27 PM+ 15 Nature R-process nucleosynthesis in magnetar-driven explosions Neutron-rich nucleosynthesis in supernovae Creating the heaviest elements Jet-driven explosions proposed as site for r- process • Low electron fraction • Medium entropy • Low density • High temperature 29 Sneden+ 08 R-process - Basics PM, Roberts, Halevi+ 17 (in prep) Halevi, PM+ 17 (in prep) 30 R-process in jet-driven supernovae Winteler+12 31 Nishimura+15 R-process in jet-driven supernovae B = 1013 G / octant 32 Halevi, PM 17 (in prep) R-process in jet-driven supernovae 100 12 2 B = 10 G / octant 10− 4 10− ] 6 10− M [ 8 10− ejecta 10 10− = M L 0 51 12 L = 10 erg/s 10− L = 1052 erg/s 10 14 − L = 1053 erg/s 16 10− 80 100 120 140 160 180 200 mass number A B = 1012 G full 3D 100 2 10− 4 10− ] 6 10− M [ 8 10− ejecta 10 10− = M L 0 51 12 L = 10 erg/s 33 10− L = 1052 erg/s 10 14 − L = 1053 erg/s 16 10− 80 100 120 140 160 180 200 PM, Roberts, Halevi+ 17 (in prep) mass number A 3) From simulations to observations From simulations to observations Full star State of the art now: Detailed simulations full physics Full 3D, full physics 0.1-1s inner core ~10000km Current frontier: 1) Engine model from full-physics simulations 2) Simplified simulations with engine model to shock breakout 35 PM, Tchekhovskoy 17 (in prep) From simulations to observations State of the art now: Future: Detailed simulations Full-star simulations full physics 0.1-1s full physics inner core ~10000km shock breakout Current frontier: 1) Engine model from detailed light curves full-physics simulations detailed spectra 2) Simplified simulations with engine model to connect observations and shock breakout engines map progenitor params 36 Summary New (hyperenergetic/superluminous) transients challenge our engine models Need detailed massively parallel 3D GRMHD simulations to interpret observational data Magnetoturbulence and large-scale dynamo action create conditions for magnetar engine Robust r-process elements only from iron cores that were magnetized strongly precollapse High-performance computing and BlueWaters key to solving these puzzles 37 Thank you! 38 Core-collapse supernovae neutrinos turbulence (Binary) black holes accretion disks EM counterparts Magnetic~ fields in high-energy astro Binary neutron stars Extreme core-collapse hyperenergetic gravitational waves superluminous EM counterparts lGRBs 39 sGRBs Core-collapse supernovae neutrinos turbulence (Binary) black holes accretion disks EM counterparts Magnetic~ fields in high-energy astro Binary neutron stars Extreme core-collapse hyperenergetic gravitational waves superluminous EM counterparts lGRBs 40 sGRBs MRI 41 MRI Basics MC Mi Mo 42 MRI Basics • Weak field instability • Requires negative angular velocity gradient • Can build up magnetic field exponentially fast • Extensively researched in accretion disks: ability to modulate angular momentum transport and grow large scale field 43 What’s the situation in core-collapse? Stability criterion: d⌦2 8⌦2 < !2 + r < 0 − BV dr [Balbus&Hawley 91,98, Akiyama+03, Obergaulinger+09] 44 Magnetorotational Mechanism M. Obergaulinger et al.: MRI in core collapse supernovae 259 • MRI works locally Akiyama+03, Shibata+06 • shearing box simulations z 13 3 Fig. 22. Volume rendered magnetic field strength of a model with b0 = 4 10 Gcomputedinaboxof1 2 1km with a resolution of 20 m at t = 21.5ms(left)andt = 37.2ms(right), respectively. The coordinate directions× are indicated as in Fig. 19×. × Obergaulinger+09max term avge term log Mϖφ / Mϖφ log Mϖφ / Mϖφ the weakest initial field, because the theoretical growth rate for 1 the fastest growing MRI mode is σMRI = 1.14 ms− for these models (see Sect. 4.2.1). 0 0.75 1.50 2.25 3 −0.25 0.25 0.75 1.25 1.75 2.25 To investigate the stability properties of large-scale channel modes as a function of the box geometry, we simulated mod- els with an initially uniform magnetic field using boxes of dif- ferent size and shape. The models were rotating according to 1 Ω0 = But1900 s− and whatαΩ = 1.25, and about their initial magnetic global field? z 13 − field was b = 4 10 Gwhenapplyingvelocitydamping z 0 × z 13 / L boundaries, and b = 2 10 Gotherwise.Wevariedboth φ 0 × 1 the ratio between the radial and vertical, Lϖ/Lz,andtheradial 45 log L and toroidal size, Lφ/Lϖ,sizeofthebox.Thegridresolution Burrows+’07 max term was 20 m (see Table B.3). Plotting the stress ratios Mϖφ /Mϖφ (Fig. 23;dampingboundaries)and M /Mterm (Fig. 24;non- ⟨ ϖφ⟩ ϖφ damping boundaries) as a function of the aspect ratio of the com- putational box, provides some indication of the range of Mϖφ values prevailing during the post-growth phase. The ratios al- low one to distinguish models with a strong variability due to 1 1 the dominant re-appearance of channel modes from those mod- log Lϖ / Lz log Lϖ / Lz els exhibiting a smooth evolutionwithoutdominantlarge-scale Fig.