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The Exhaust System of the Most Powerful Engines: Production and Evolution of Relativistic Astrophysi

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3-D MHD Studies of Kinetic Flux Dominated (KFD) Jets ... 2-D MHD Large Scale, Long Term, NON-Self-Similar Numerical Models of Accelerating PFD Jets ... – PowerPoint PPT presentation

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Title: The Exhaust System of the Most Powerful Engines: Production and Evolution of Relativistic Astrophysi


1
The Exhaust System of the Most Powerful Engines
Production and Evolution of Relativistic
Astrophysical Jets
  • David Meier
  • Jet Propulsion Laboratory/Caltech
  • ATP Grant (FY 07-09) ? Collaborators
  • P.C. Fragile (C of C) M. Nakamura (LANL) S.
    Markoff (U. Amsterdam)
  • P. Polko (U. Amsterdam) D. Garofalo (JPL)

Nakamura, Uchida Hirose (2001)
Meier, Uchida Koide (2001)
2
Accreting Black Holes Produce Jets
SUPERMASSIVE BLACK HOLES
STELLAR-MASS BLACK HOLES
GRO J1655-40
M 84 (3C 272.1)
  • It also is believed that jets are produced
    whether the black hole is spinning rapidly or
    not, but there is quite a range in jet power (gt
    104-5) even for black holes of very similar mass
    and accretion rate. So, BH spin also may be
    important.

3
The Five Regions of Jet Propagation From the
Lobes Inward(AGN vs. 10 M? ?QSR _at_ 3 kpc)
  • Hot Spot/Lobe 109 rS (100 kpc or 20 100 AU
    or 60 mas)
  • ? Outer jet may not be Poynting-Dominated
  • Kinetic-Flux-Dominated (KFD) Jet 103 109 rS
    (0.1 105 pc or 1
    mas 20 5 R? 100 AU or 60 nas 60 mas)
  • Transition Region 102.5?0.5 rS

    (lt 0.1 pc or lt 1 mas lt 5 R? or lt 60 nas )
  • Poynting-Flux-Dominated (PFD) ? KFD
  • MHD Acceleration/Collimation Region 10
    102.5?0.5 rS (1
    lt 100 mpc or 10 ?as lt 1 mas 300 km lt 5 R?
    or 0.6 lt 60 nas)
  • The Jet Nozzle
  • Jet Launching Region The Accretion Flow 5
    50 rS (0.5 5 mpc or 5
    50 ?as 150 1500 km or 0.3 3 nas)
  • Black Hole accretion disk region

4
(No Transcript)
5
Relativistic MHD of Black Hole Jets, Accretion,
and Formation
  • David Meier
  • Jet Propulsion Laboratory/Caltech
  • ATP Grant (FY 07-09) ? Collaborators
  • P.C. Fragile (C of C) M. Nakamura (LANL) S.
    Markoff (U. Amsterdam)
  • P. Polko (U. Amsterdam) D. Garofalo (JPL)

Nakamura, Uchida Hirose (2001)
Meier, Uchida Koide (2001)
6
Talk Outline Relativistic MHD of Black Hole
Jets, Accretion, and Formation
  • The Basic Astrophysics Theory Program Grant (5
    tasks, from the outside in)
  • 3-D MHD Studies of Kinetic Flux Dominated (KFD)
    Jets
  • 3-D MHD Studies of Poynting Flux Dominated (PFD)
    Jets
  • Semi-Analytic MHD Extension of Markoff et al.s
    Models of Broad-Band Jet Emission
  • 2-D MHD Large Scale, Long Term, NON-Self-Similar
    Numerical Models of Accelerating PFD Jets
  • Studies of Cooled Black Hole Accretion Flows and
    Development of Jet-Producing Black Hole
    Magnetospheres (MDAFs)
  • What will the Next Generation of Astrophysical
    MHD Codes Look Like? Full Evolving General
    Relativistic MHD (EGRMHD) With Matter and
    Current Sources
  • Talk Summary

7
General Strawman Theoretical Picture
  • Jets are launched in the rotating magnetospheres
    of black hole accretion inflows how these
    magnetospheres are set up is still poorly
    understood

Uchida Shibata 1986 Uchida et al. 1999
Nakamura 2001
  • After launching, jet continues to be accelerated
    and collimated
    by the rotating magnetic field for
    very large distances
  • MHD jets have 3 singular points (Blandford
    Payne 1982 Vlahakis Konigl 2004)
  • A key feature of this picture is the prediction
    of an acceleration termination shock produced by
    a super-magnetosonic flow that naturally
    undergoes a strong pinch (cf., Lind, Payne,
    Meier Blandford 1989)
  • Beyond the MFP and collimation shock, the
    structure of the jet is unclear, and may depend
    on the parameters of the flow
  • Kinetic Flux Dominated (KFD), tangled magnetic
    field
  • Poynting Flux Dominated (PFD), helical field

8
3-D MHD Studies of KFD (V gt Vfast) Jets
(Nakamura, Garofalo, Meier)
  • What is the Full 3-D Structure and Evolution
    of the Jet Flow Through a Collimation Shock?
  • Clarke et al. (1986) and Lind et al. (1989) were
    2-D, toroidal field only studies
  • How does adding in the poloidal magnetic
    component change things?
  • How does adding full 3-D evolution change things?
    Does the jet become fully turbulent beyond the
    collimation shock?
  • Does the jet remain Kinetic Flux Dominated in
    this post-shock flow?
  • Or, does the jet revert to a Poynting Flux
    Dominated flow?
  • Are both PFD KFD possible, depending on the
    parameters (i.e., FR II or FR I-type structure)?
  • How does behavior differ between non-relativistic
    and relativistic flow?

9
Are Relativistic PFD Jets Stable?
(Nakamura, Garofalo, Meier)
Potentially unstable to helical-kink (m1
current-driven) instability note m0 is the
pinch
  • Two issues (Nakmura Meier 2004)
  • Issue 1
  • Does the helical kink disrupt the jet?
  • No, jet opens up to produce a larger helix with
    fewer net turns
  • However, this still could drastically change
    position of MFP
  • Issue 2
  • Is the classical, static Kruskal-Shafranov
    stability criterion correct?
  • No, rotational inertia of the jet can stabilize
    well beyond this point! Jet is not force-free
  • Opens up the possibility that relativistic jets
    may have self-inertia that stabilizes them

Nakamura, Uchida Hirose (2001)
0
0
Nakamura Meier (2004)
10
The Nakamura Hybrid Inter-cell Flux Method Roe
Accuracy without the Roe Work
  • Hybrid scheme time averages
  • Godunov-type (HLL) at tn
  • Centered at tn1
  • Only 1 characteristic speed needed (cf )
  • Comparison with Roe linearized Riemann solver
    (20 tests)
  • Equivalent for most problems
  • Better for a few
  • Worse for a few
  • Advantages
  • Easy to implement
  • Fewer HUMAN computations
  • Fewer CPU computations
  • Nakamura has working for both
  • Newtonian HD, MHD (1-3D)
  • Relativistic HD, MHD (1-2D)

11
Semi-Analytic MHD Extension of Markoff et al.s
Models of Jet Broad-Band Emission (Polko,
Markoff, Meier)
GX 339-4
Markoff Nowak (2004)
  • Markoffs shock (needed for particle
    acceleration) may be the collimation shock
    predicted by Vlahakis Konigl MHD jet theory
  • Position of the collimation shock is then 50
    500 rS from the black hole
  • Vlahakis Konigl (2003) self-similar models will
    be substituted for the HD jet model
  • Fit modified slow point onto Seras corona fit
    modified fast point (region) onto Seras particle
    accelerating shock

12
Semi-Analytic MHD Extension of Markoff et al.s
Models of Jet Broad-Band Emission (continued)
  • Questions
  • Can VK-type, self-similar models be fit to the
    broad band data?
  • Is the position of the predicted collimation
    shock (?zMFP) consistent with the strong shock
    needed in Seras broad-band models to accelerate
    synchrotron-emitting particles?
  • Which parameters are robust (similar in both the
    HD and MHD models)?
  • Which parameters change significantly when MHD is
    introduced?
  • Does MHD imply a different picture of the jet
    than HD?
  • Can these models be used as diagnostics of the
    jet flow?

13
Large Scale, Long-term, 2-D, NON-Self-Similar
Numerical Models of Accelerating PFD Jets
(Nakamura, Meier, Markoff, Polko)
  • Goals
  • Eventual goal is to substitute numerical
    simulations for VK self-similar models
  • Immediate goal is to understand differences
    introduced in jet acceleration by relaxing
    self-similar assumption of Vlahakis Konigl
  • Similar to McKinneys single calculation, but he
    never found a true MFP
  • Quesions
  • Can we identify modified slow/fast points in the
    simulated flow?
  • In particular, can we identify an MHD causality
    limit (analogous to the MFP) where the jet
    outflow becomes disconnected from inner engine
    AND where flow becomes KFD?
  • Does formation of an MFP/causality limit depend
    on the physical parameters of the flow?

14
Studies of Cooled Black Hole Accretion Flows and
Possible Development of Jet-Producing
Magnetospheres (Fragile Meier)
  • The three stages of MDAF formation, predicted
    from analytic models (Meier 2004)
  • Final structure should look similar to
  • black hole magnetosphere models of
  • Tomimatsu Takahashi (2001) and Uzdensky (2004)

15
Studies of Cooled Black Hole Accretion Flows and
Possible Development of Jet-Producing
Magnetospheres(continued)
  • We are using Chris COSMOS code (Anninos,
    Fragile, Salmonson 2005) to test out each stage
    of this model
  • We have added Esin et al. (1996) cooling
    functions (Bremsstrahlung, Synchrotron,
    Comptonization) to COSMOS
  • Questions
  • Does cooling always lead to an optically thick,
    cool (107 K) disk, or can it leave a highly
    magnetized, warm (109-10 K) optically thin flow
    that is NOT advection dominated?
  • Does cooling increase the strength and structure
    of the magnetic field as predicted by the MDAF
    model?
  • Does a true black hole magnetosphere form in some
    circumstances? If so, when and what controls its
    formation?
  • Do the resulting rotating black hole
    magnetospheres say anything about jet launching
    from hard state objects?

16
Major Issues and Progress
  • Starting off MRI simulations
  • Unstable starting conditions?
  • Small field vs. large field (i.e., high ? vs. ? ?
    1)
  • What happens after the final critical point?
  • Observations largely show still fairly
    well-ordered field
  • BL Lac and other FR I-types
  • But also 3C 273 (not much on FR II-types)
  • Do ALL jets remain PFD out to the jet lobes?
    That is, is MHD necessary for the ENTIRE length
    of all jets?
  • Do SOME jets become KFD beyond the nucleus? That
    is, can HD be sufficient for the gt few pc - kpc
    scale?
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