Title: The Exhaust System of the Most Powerful Engines: Production and Evolution of Relativistic Astrophysi
1The 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)
2Accreting 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.
3The 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
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5Relativistic 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)
6Talk 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
7General 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
83-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?
9Are 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)
10The 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)
11Semi-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
12Semi-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?
13Large 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?
14Studies 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)
15Studies 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?
16Major 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?