Numerical Simulations of Relativistic Jets Peng Wang KIPAC July 7, 2008 SLAC Annual Program Review

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 July 7, 2008 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. July 7, 2008 SLAC Annual Program Review

SLAC Annual Program Review The codes The complexity of the problem requires a multi-scale & multi-codes approach: Large scale jet propagation Renzo: 3D adaptive mesh refinement (AMR) relativistic hydro code (PW, Tom Abel, Weiqun Zhang) Jet production by GRMHD effect NVWA: 3D GRMHD code (Weiqun Zhang, PW) Black hole accretion disk at parsec scale Enzo-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. July 7, 2008 SLAC Annual Program Review

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 July 7, 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 using the same setup. NVWA code: Weiqun Zhang & PW July 7, 2008 SLAC Annual Program Review

Jet collimation & acceleration by wind Problem setup: A non-relativistic wind with polar density stratification is injected spherically. Demonstrate that the interaction with the denser outer part can lead to efficient acceleration & collimation (up to Lorentz factor 11 in this particular run). NVWA: PW, Zhi-Yun Li & Weiqun Zhang July 7, 2008 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. July 7, 2008 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 disk may provide EM counterpart to LISA observations that can be observed by LSST. Enzo-MHD: PW & Andres Escala July 7, 2008 SLAC Annual Program Review

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. July 7, 2008 SLAC Annual Program Review