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Numerical Simulations of Relativistic Jets. Peng Wang KIPAC. Overview. Why we study jets How we study jets: the codes Some (preliminary) results on * 3D relativistic hydro jet propagation * Jet production by GRMHD effect * Binary black hole evolution. Why jets are interesting.
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Numerical Simulations of Relativistic Jets Peng Wang KIPAC SLAC Annual Program Review
Overview • Why we study jets • How we study jets: the codes • Some (preliminary) results on* 3D relativistic hydro jet propagation* Jet production by GRMHD effect* Binary black hole evolution SLAC Annual Program Review
Why jets are interesting • GLAST will see up to 10^4 blazars which are relativistic jets pointed at us (Blandford & Rees 1978). • Ideal lab for studying the physics of relativistic (magneto-)hydro turbulence and particle acceleration • Provide constraints on the center engine • AGN feedback are crucial for galaxy formation Thus, jet is a hot topic. GLAST will make great progress in nailing down whether jet is really hot! We are simulating them so as to use the data to answer the fundamental questions about how they work. SLAC Annual Program Review
The codes • The complexity of the problem requires a multi-scale & multi-codes approach: • Large scale jet propagationRenzo: 3D adaptive mesh refinement (AMR) relativistic hydro code (PW, Tom Abel, Weiqun Zhang) • Jet production by GRMHD effectNVWA: 3D GRMHD code (Weiqun Zhang, PW) • Black hole accretion disk at parsec scaleEnzo-MHD: 3D AMR Newtonian MHD code (PW, Tom Abel) • See also Matt Turk’s talk for other applications of AMR codes, e.g. in cosmological structure formation. SLAC Annual Program Review
Jet propagation • Problem setup:Lorentz factor 5 jet injected into a medium in pressure equilibrium with the jet. • Demonstrate the development of turbulence in jet cocoons. Renzo code: PW, Tom Abel & Weiqun Zhang, ApJS 2008 SLAC Annual Program Review
Jet production by BZ effect • Problem setup:A equilibrium thick disk with a tiny seed magnetic field around a Kerr black hole with spin 0.9 • Demonstrate the development of magneto-rotational instability in the disk and production of a Poynting flux dominated jet by the Blandford-Znajek mechanism.Agrees with many other groups usingthe same setup. NVWA code: Weiqun Zhang & PW SLAC Annual Program Review
Jet collimation & acceleration by wind • Problem setup: A non-relativistic wind withpolar density stratification isinjected spherically. • Demonstrate that the interactionwith the denser outer part can lead to efficient acceleration &collimation (up to Lorentz factor11 in this particular run). NVWA: PW, Zhi-Yun Li & Weiqun Zhang SLAC Annual Program Review
Future direction: comparing simulations to observations • Perform ray-tracing through the simulated data to predict the observed gamma rays and radio flux. • Also need to add magnetic field to large scale propagation study in order to compare to GLAST observation. SLAC Annual Program Review
A Possible LSST candidate: Circumbinary Black Hole Disk • Problem setup:A binary massive black hole embedded in a gaseous disk. • Emission from the inner diskmay provide EM counterpartto LISA observationsthat can be observed by LSST. Enzo-MHD: PW & Andres Escala SLAC Annual Program Review
Summary • Forthcoming observations from GLAST & LSST is likely to advance significantly our understanding of black hole/jet systems. • Exciting observations need exciting simulations. SLAC Annual Program Review