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EU Astrophysics Network Overview: 

EU Astrophysics Network Overview Ed Seidel Albert-Einstein-Institute Principal Network Coordinator Progress on 3D BH Collsions (me) 3D Hydro (Luciano) Stellar Instabilities (Nils) LIGO-G020158-00-Z

Objectives of NetworkA Training program to build a community: 

Enablers Focus Physics Areas Outreach /Leverage GridLab ZIB/Garching LBL/NCSA/ANL Cactus Community NSF ASC 3D BH Collisions Other (strange stars, Core collapse, etc) 3D NS processes and mergers World Objectives of Network A Training program to build a community People 65:10!

Our Team7 Focus areas, links created, strengthened by Network: 

Our Team 7 Focus areas, links created, strengthened by Network Valencia Ports SOTON Meudon Jena Palma Trieste AUTH Rome WashU Potsdam Jena

Steps to BBH Orbits(AEI/UT-Brownsville/Meudon): 

Steps to BBH Orbits (AEI/UT-Brownsville/Meudon) Step 0: Better Formulations (BSSN), gauges, excision Step 1: Do 3D single, rotating distorted BHs individually t ~ 100s - 1000s M with convergence, solid masses, waveforms Some instability may appear after t ~ 200 - 500M in full 3D Step 2: Do head -on BH collisions 100s - 1000s M with convergence, solid masses, waveforms Step 3: Go to co-rotating frame for orbits! Can just about do this today…

Step 1:Single 3D BHs Become “Routine”: 

Step 1: Single 3D BHs Become “Routine” Comparison of Schwarzschild BHs

Step 2: 3D Head-On Collisions “Routine”: 

Step 2: 3D Head-On Collisions “Routine” Brill-Lindquist Approx ISCO separation No momentum Similar to Misner m=2.2 New dynamic shift/lapse combo No Excision!!! Time (M) AH Mass 5000 0 From Peter Diener…

Step 3: Co-rotating frame for Orbits: 

Step 3: Co-rotating frame for Orbits New Techniques Excision Gauges, formulations Co-rotating frame Baumgarte initial data Estimated Innermost Stable Circular Orbit (ISCO) Other circular orbits, too (“Pre-ISCO” sequence: PI-1-10) From Denis Pollney…

Overview of Evolutions So Far: 

Overview of Evolutions So Far Major problem is finding data sets that want to orbit! Baumgarte data Seem to have momentum too low for circular orbits W seems to be overestimated by factor of 2 Evolutions solid (e.g., horizon mass accurate to 10% at t~100M) Pre-ISCO model Time (M)

Example: Pre-ISCO 3: 

Example: Pre-ISCO 3 Kzz in x-y plane, showing excision (corotating) AHs and Y4 (Corotation taken out)

Increasing sophistication in IVPGrandclement (Meudon) BBH data: 

Increasing sophistication in IVP Grandclement (Meudon) BBH data Meudon Group: most astrophysically relevant binary BH data to date. Now in Cactus as EU Network Project Builds in approx helical Killing vector Has orbital period of ~ 2x that of potential method (also what we see in evolutions!) Post-Newtonian expansions seem to converge towards the numerical BBH data (from Luc Blanchet)

GridLab: www.gridlab.org Enabling Dynamic Grid Applications: 

GridLab: www.gridlab.org Enabling Dynamic Grid Applications EU Project (€5M) AEI, ZIB, PSNC, Lecce, Athens, Cardiff, Amsterdam, SZTAKI, Brno, ISI, Argonne, Wisconsin, Sun, Compaq Grid Application Toolkit for application developers (APIs/Tools) Develop new grid scenarios for 2 main apps: Numerical relativity Grav wave data analysis

Discovery Channel wantsPre-ISCO 3! This June…: 

Discovery Channel wants Pre-ISCO 3! This June…

Building a Community (through) Code: Advantages: 

Building a Community (through) Code: Advantages Sharing of Expertise: No single group or community can do these problems Sharing of Code among projects Infrastructure BH routines apply directly to NS work, etc… But free to keep routines in group as long as desired Better Code Open source encourages people to be more careful in coding! Encourages documentation Encourages deeper thinking about how it interfaces to another code More trusted code, results When code becomes open, and people can run it for themselves, they will begin to believe the results Improvements propagate quickly though community Not well accepted yet, but we are starting a good trend…

Cactus User CommunityUsing and Developing Physics Thorns: 

Cactus User Community Using and Developing Physics Thorns Goddard Wash U AEI TAC Tuebingen Soton SISSA Thessaloniki Meeting in May: Theoretical Foundations of Einstein’s Equations for Numerical Relativity (Using Cactus to investigate and compare different implementations) Climate Modeling (NASA,AMS) Chemical Engineering (U.Kansas) Bio-Informatics (Canada) Geophysics (Stanford) Astrophysics (Zeus) Plasma (Princeton) EU Astrophysics Network NASA Early Universe (LBL) Numerical Relativity/Astrophysics Other Applications Portsmouth RIKEN Monash Pitt UT PSU UNAM Etc… Arizona

Previous 3D BH Resultsnew formulations, no shift, no excision: 

Previous 3D BH Results new formulations, no shift, no excision Grazing Collision 1999 Big Advance: 3D, unequal mass, spin, J Physics! But Code crash by 40M

Horizon Mass for Pre-ISCO 4: 

Horizon Mass for Pre-ISCO 4 Low resolution (192x192x96), but mass conserved to ~ 10% until ~100M Now exploring parameters to find orbital configurations