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Jet Formation and Propagation in Black Hole Accretion Systems. Speaker: Jonathan C. McKinney Ann Arbor : Dec 17, 2005. McKinney (2005) (a,b,c) McKinney & Gammie (2004) Gammie, Shapiro, McKinney (2004) Gammie, McKinney, Toth (2003). Why Study Jets?. “Pathological” energy-momentum transport
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Jet Formation and Propagation in Black Hole Accretion Systems Speaker: Jonathan C. McKinney Ann Arbor : Dec 17, 2005 McKinney (2005) (a,b,c) McKinney & Gammie (2004) Gammie, Shapiro, McKinney (2004) Gammie, McKinney, Toth (2003)
Why Study Jets? • “Pathological” energy-momentum transport • Accretion disks common • Jets produced in: • YSOs, WDs, NSs, BHs • Supersoft X-ray sources, symbiotic stars, classical novae, but not CVs • Not so “pathological” • Non-negligible to energy and radiative budget
Black Hole Accretion Systems 1038erg/s M~10M¯ 1052erg/s M~3M¯ 1044erg/s M~107M¯ Mirabel & Rodriguez (Sky & Telescope, 2002)
Outline • Black hole energy extraction • Numerical GRMHD model • Segmented accretion flow structure • Disk/Wind/Jet field geometries • Large scale Poynting jet • Piece-wise self-similar • Inner parabaloidal jet and conical exterior
Kerr Black Hole • Properties: • Spin: J • Mass: M • Up to ~30% of mass energy extractable Ergosphere • Examples: • GRB with M» 3M¯ • E»1054 ergs • L»5£ 1052 erg s-1 • AGN with M» 108M¯ • E»5.6£ 1061 ergs • L»3£ 1010 L¯ s-1 Event Horizon BH Ergo
Blandford & Znajek Poloidal Field • Assumptions: • Kerr BH (small j) • Force-free ED or EM>MA • Axisymmetric • Stationary Disk • Solve: • Force-free equations (JxB=0) • OR • Conservation equations • Find: • Outward Flux of Energy • Magnetic Field Structure • (monopole or parabolic)
Poloidal Field Disk GRMHD • Assumptions: • Kerr BH • Matter + fields (MA+EM) • Ideal MHD, ideal gas • Axisymmetric • Nonradiative • Initial hydro-equilibrium torus • Time-dependent • Solve: • Conservation equations • Induction equation with r¢B=0 constraint • Find: • Mass density & internal energy • Velocity & magnetic field
M87 Jet Formation Junor (1999) & Biretta (1999,2002)
Numerical Model Log Mass Density Parameters:
Initial State Poloidal Field
Mass and Field Structure Log of mass density Poloidal Field • Evacuated polar region • Turbulent equatorial region • Ordered polar field • Random equatorial field
Flow Structure Poynting Jet “Matter” Jet CORONA: MA~EM FUNNEL: EM dominated JETS: Unbound, outbound flow DISK: Matter dominated PLUNGING: MA~EM
9 7 5 4 1 3 2 8 6 Common Field Lines Balbus & Hawley (MRI) [1] Gammie & Krolik [2,3] Effect of reconnections [4,5] Lovelace or Blandford-Payne [6,7] Konigl & Vlahakis [6,7,~9] Uzdensky, Matsumoto [8] Blandford & Znajek [9] Final State Time Avg. State Common Temporary Never
Large Scale Jet • Outer Radius : 104 GM/c2 • 0.001AU for XRBs • 0.1R* or 1010 cm for GRB • 1.4pc for M87 • Final Time : 104 GM/c3 • 0.1-1s for XRBs • 0.1s for GRB • 5yrs for M87
Large Scale Jet AGN/XRB-like GRB
Kink Stability • Kruskal-Shafranov criterion for instability • Tomimatsu (2001) criterion for instability (slow rotation approximation)
Piece-wise SS Small radius (r<~100M) Large radius
Characteristic Surfaces B/Br=1 Field Lines O-Fast Light “Cylinder” O-Alfvén O-Slow B/Br=1 vr=0 I-Slow I-Alfvén Null (F=ZAMO) I-Fast / Horizon Ergosphere rin
GRMHD Summary • Segmented flow structure • BZ-like funnel region • Self-consistent, relativistic jets • Poynting outflow is Large • Matter+Poynting outflow » 1-3