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Vacuum BH Studies AEI, Meudon, Palma, UPHEC. Organization All evolutions, most data sets generated in Cactus AEI carries out most evolutions, Palma collaboration Meudon generating better BBH initial data, in CVS, Cactus Techniques, codes transferred to other projects (e.g. NS-NS, …)
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Vacuum BH StudiesAEI, Meudon, Palma, UPHEC • Organization • All evolutions, most data sets generated in Cactus • AEI carries out most evolutions, Palma collaboration • Meudon generating better BBH initial data, in CVS, Cactus • Techniques, codes transferred to other projects (e.g. NS-NS, …) • UPHEC developing nonlinear perturbation studies www.eu-network.org Sources of Gravitational Radiation
Post-Newtonian Need Post-N BH Initial data gap Standard Numeical relativity: Exciting new results, get farther and farther… Perturbative Colliding BH Roadmap:A patchwork to success Merger Phase Technique Time Scale Post Newt inspiral t ~ 500+ M t ~ 100 M Final Plunge t ~ 30 M Ringdown Time www.eu-network.org Sources of Gravitational Radiation
Distorted rotating BH'smodeling the late stages of BH coalescence, perturbative comparisons Uses excision, New gauges, Forms basis for what comes next… Remarkable agreement between 2D and 3D! Crash! 2D runs crashes! www.eu-network.org Sources of Gravitational Radiation
3D BH Work • Grazing Collision just published in PRL last month • New formulations of EE’s made it possible, but • no shift • no excision • no co-rotation www.eu-network.org Sources of Gravitational Radiation
“ISCO” series Initial Data • Baumgarte studied initial data • Equal mass, nonspinning BHs • Computer distance, momentum parameters for circular orbits • Estimated Innermost Stable Circular Orbit (ISCO) • Other circular orbits, too (“Pre-ISCO sequence: PI-1-10) • Here concentrate on PI-3 • Now almost able to do orbits • Not yet, but probably can, and probably not needed! • Problem: data sets so far coalesce before orbit! But code fine! • This is extraordinary • Many of same techniques apply directly to binary NS, binary strange stars, etc. www.eu-network.org Sources of Gravitational Radiation
Quantitative Analysis Apparent Horizon Mass l=m=2 ZerilliWaveform M Y Time (M) Time(M) Merger at t = 25M www.eu-network.org Sources of Gravitational Radiation
Meudon Binary BH Initial Data • OP Group has generated most astrophysically relevant binary BH data to date • How good? Recent Post-N work at Paris indicates it is very good! • These data sets already imported into Cactus due to Network activities • Same interface as their binary NS data, also in Cactus! www.eu-network.org Sources of Gravitational Radiation
Conclusions • I have waited many years to see such results • 1D broke through barrier in 1987 • 2D in 1993-5 • 3D got stuck until last year… • Why is all this happening now? • We have a great team! (Critical mass, talent, focus, coll) • Developed much better theoretical understanding/practical experience. • We developed great collaborative technology • 3+1 codes have smashed through the t = 30M barrier • Shift to cure grid-stretching, co-rotation • Orbits seems possible, but may not be necessary… • All this applies to NS-NS and other problems! www.eu-network.org Sources of Gravitational Radiation