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Exploding Massive Stars: The Perfect ‘App’ for Computational Physics John M. Blondin North Carolina State University SESAPS 2003 What is a supernova? A single, new star outshines an entire galaxy for weeks. QuickTime™ and a Sorenson Video decompressor are needed to see this picture. The High-Z Supernova Search QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. The High-Z Supernova Search QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. The Crab Supernova Remnant This debris is located in the same position as a supernova seen by Chinese astronomers in 1054. Historical Supernovae Year Report Status 1006 China, Arab lands, Europe Identified with radio SNR 1054 China, Japan Crab Nebula 1181 China, Japan SNR 3C58 1572 Europe (Tycho Brahe), China Tycho's remnant 1604 Europe (Kepler), Japan, Korea Kepler's remnant Cassiopeia A Radio Optical X-Ray What are we looking at? •Brightness & distance => 10 billion Suns •Doppler shifts => expansion at 1000 km/s •X-Ray emission => few solar masses An expanding blastwave with 1051 ergs Where did all that energy come from? Type Ia - stellar-sized nuclear bomb Type II - gravitational collapse of a massive star SN1987A confirmed the basic supernova theory •A star disappeared! Supernovae do result from the death of a massive star. •Neutrinos were detected (2002 Nobel Prize), confirming formation of neutron star in the core. What is left to learn? • How do they explode?! • What is the neutrino signature? • Do they produce gravitational waves? A Brief History of Supernova Theory • 1957 Burbidge, Burbidge, Fowler, and Hoyle Thermonuclear runaway in envelope • 1966 Colgate and White Neutrino-Driven prompt explosion • 1985 Bethe and Wilson Shock reheating via neutrino energy deposition • 1992 Herant, Benz, and Colgate Convective instability above neutrino-sphere Need Boltzmann Solution Need Angular Distribution Need Spectrum Need Neutrino Distribution Fluid Instabilities Rotation Magnetic Fields Need these to few percent accuracy! 6D RMHD Problem! TeraScale Supernova Initiative http://www.phy.ornl.gov/tsi/ Explosions of Massive Stars Relevance: Element Production Cosmic Laboratories Driving Application 10 Institution, 17 Investigator, ~ 40 Person, Interdisciplinary Effort ascertain the core collapse supernova mechanism(s) understand supernova phenomenology e.g.: (1) element synthesis, (2) neutrino, gravitational wave, and gamma ray signatures provide theoretical foundation in support of OS experimental facilities (RHIC, SNO, RIA, NUSL) develop enabling technologies of relevance to many applications e.g. 3D, multifrequency, precision radiation transport serve as testbed for development and integration of technologies in simulation “pipeline” e.g. data management, networking, data analysis, and visualization With ISIC and other collaborators: ~120 people from 24 institutions involved. What will it take? Tera/Peta-Scale 3D, General Relativistic, Radiation Magnetohydrodynamics State of the Art Nuclear and Weak Interaction Physics “Infrastructure” Needs: Applied Mathematics Tera- and Peta-Scale Sparse Linear Systems of Equations “Infrastructure” Needs: Data Management/Visualization 1-10 Tb/Variable/Simulation! Manage? Analyze? Render? “Infrastructure” Needs: Networking How can a nationally distributed team work together effectively? Messer et al. (2002) Liebendoerfer et al. (2002) No Explosions! New Microphysics? High-Density Stellar Core Thermodynamics TSI will explore both! Neutrino-Matter Interactions New Macrophysics? (2D/3D Models) Fluid Instabilities, Rotation, Magnetic Fields No 2D/3D supernova models with realistic neutrino transport exist! One Dimension is Too Simple Quic kTime™ and a YUV420 codec decompress or are needed to s ee this picture. QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. SAS Solution is Stable in One Dimension Pressure perturbation QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. radius time QuickTime™ and a Video decompressor are needed to see this picture. SASI: l=1 mode is overstable Spherical shock Shock normal Radial in-fall The obliquity of the accretion shock deflects the radial in-flow QuickTime™ and a Video decompressor are needed to see this picture. Challenges in Data Management QuickTime™ and a Animation decompressor are needed to see this picture. QuickTime™ and a Animation decompressor are needed to see this picture. First steps toward understanding the role of magnetic fields… What impact will they have on the collapse and postbounce dynamics? How much do they factor into generating the explosion? How much will they be amplified, and how? Wrapping Dynamo Magnetorotational Instability (Balbus and Hawley 1991) Akiyama et al. (2002) QuickTime™ and a BMP decompressor are needed to see this picture. SASI + Dipole Field Asif ud-Doula (see poster) How did this happen?!