Is the Formation of Relativistic Jets a Fiction 30 Years BZ Mechanism

1
Is the Formationof Relativistic Jets a Fiction
?- 30 Years BZ Mechanism

• Max Camenzind
• Landessternwarte Königstuhl
• Center for Astronomy HD
• 3rd Tapas Workshop Granada

2
Topics

• Formation of relativistic jets in stationary
  approach understood rotating MS, plasma
  injection, acceleration and collimation.
• Correlation between X-ray states and Jet
  production (in micro-quasars, RXTE).
• Sc1 Weak field limit GRMHD MRI simulations
  produce outflows, which are ?
  non-relativistic, not collimated
  ? Model for micro-quasars ?
• Sc2 Strong field limit MAES
  Blandford-Znajek in magnetospheres.

3
Are Relativistic Jets Plasma Flows Driven away
from the Ergosphere ?
4
What it should be
Equilibrium in transverse direction between differ
ent forces (Camenzind 1997).
Towards VLBI Core Acceleration Region Poynting
flux ? kin. Energy
BH
5
Jet Formation Ingredientsare known from
Stationary MHD

• Strong magnetosphere with rapid rotation (disk
  around BHs).
• Plasma injection (disk plasma, pairs from MS²).
• High initial Poynting flux (BZ) is converted into
  kinetic energy by collimating flux-tubes
  ? Michels parameter G s 10 (Camenzind)
  (s Poynting flux / Total
  energy flux, Michel).
• Flux-tubes are collimated by current system.
• Mass of a BH is not essential, is it the spin a ?

6
New Insights (RXTE) forMicro-Quasar Disk-Jet
Connection

• 1996 1997 Outburst
• Red thermal emission
• Blue Hard State
• Green steep power-law (SPL)
• State transitions not detectable in Quasars ? Mio
  yrs time-scales

Remillard 2005
7
DIFFERENT BINARY SYSTEMS

• type of the donor star ? type of accretion (wind
  or Roche lobe overflow)
• very different scales

J.A. Orosz
Every X-ray binary is a possible microquasar!
8
Stellar Mass Spectrum? Clear Separation NSs vs
BHs
BHs
NS
9
Black Hole Two-Hair Plane
Microquasars, Stellar BHs, M gt 30
RL Quasars, Radio Galaxies BH s in Galactic Cente
rs and QSOs
Intermediate Mass BHs ??? Population III BHs
BHs at High Redshifts
Neutron Stars
Camenzind 2005
10
X-Ray EmissionVARIABILITY on all Time Scales
GX339-4 lightcurve

• Variations changes in the state of the source
• lightcurves
• GX 339-4 / GRS 1915105
• ? Variations on very different time scales !
• ? easy observations for human time scale

1996
2003
GRS 1915105
X (2-10 keV)
Radio (2,25 GHz)
Rau et al (2003)
11
X-Ray States of Cyg X-1

• High Soft
• State (HS)
• BB Disk
• Emission
• Power-Law
• Low Hard
• State (LH)
• Comptoni-
• sation of
• soft Photons

12
Active Accretion States of BHBs
critical State
physical element ? 3. steep power law
compact corona G 2.4-3.0, rms lt 0.15 fpowgt
80 or fpowgt 20 QPOs ?
thermal accretion disk fpow lt 20, no
QPOs, ? hard state steady jet
fpow gt 80, G 1.5-2.1 rms (PDS) gt
10
Energy spectra Power density spectra
Energy (keV)
Frequency (Hz)
13
The Third Dimension
SPL
Thermal
Hard State
Esin et al. 1995 A. Müller (LSW 2004) Remillard
2005
14
Fender et al. 2004, refined by McClintock
Remillard 2005, Remillard 2005
15
Jet On Off States in Micro- Quasars
Jets off
Jets on
Remillard 2005
16
High Frequency QPOs in Micro-Quasars in SPL ?
Inner edge of disk is near ISCO
n0 930 Hz / M Kepler, but where ?
Remillard 2005
17
Black Hole Accretion isDifferent from
pseudo-Newtonian
In ergoregion, plasma is driven to corotation
with horizon.
Müller LSW 2004
18
Each form of matterwill be driven to
corotationwithin the ergosphere !? Boundary
Layer near Horizon r
WH w(r)

• In Schwarzschild
• No rotation
• near Horizon !

19
a 0.5
a 1.0
20
Sc1 GRMHD Accretion from a Torus? Non-Radiative
Accretion Flows

• De Villiers,
• Hawley
• Krolik 2003
• 2005
• (3D non-conservative
• GRMHD in BL)
• Gammie et al.
• 2003, 2004
• (2D conservative
• GRMHD
• in BL coordinates)

Initial condition (exact mech. equilibrium weak
magnetic fields)
21
Meridional Plane through a BH Colour Density
Funnel
Outflows
Turbulent Thick Disk ? Keplerian
Torus weak magnetic fields
Initial State
Final State
Gammie et al. 2004
22
OutflowsinMicro-Quasars
Krolik 2005
23
Relevance of Poynting Flux relative to
total energy flux
Krolik et al. 2004
24
Consequences (Krolik 2004)

• For high spin (a gt 0.8), Poynting flux is always
  flowing away from horizon into the disk.
• For high spin, most of the Poynting flux goes
  into the funnel outflow (jet).

25
Sc2 GRMDH Strong Field LimitRESISTIVE BH
ELECTRODYNAMICS
Covariant
31 form
Equations

• Kerr-
• Schild
• Coordinates
• bc inside
• Horizon

Constitutive
a, b - lapse function and shift vector
(space-time metric)
Komissarov 2004
26
Electrodynamics is a prioriin Conservative Form
Div(B) 0
Induction equation
27
RESISTIVE BH ELECTRODYNAMICS
Ohms Law
(no particle inertia)
- drift current
- anisotropic conductivity
Typical conditions of BH and pulsar
magnetospheres
In current sheets
or even
Komissarov 2004
28
Insights into Blandford-Znajek Process

• Example Wald solution (non-rotating) ? Testbed
  for Blandford-Znajek
• Field lines connected to ergosphere are driven
  to rotation
• Poynting flux ? Energy extraction from
  ergosphere !

W
2
2
Kerr black hole in uniform magnetic field at
infinity Thin plasma version. BH
magnetosphere. a 0.9 Komissarov 2004
B - E
29
? BH Magnetosphere is driven to Rotation only
inside the Ergosphere ! ? BZ Mechanism works,
but not Horizon driven, as originally proposed !


30
Conclusions

• Jet-Disk connection is very complex, as shown by
  micro-quasars. Jet formation can only be solved
  including accretion (QPOs).
• GRMHD MRI (on Kerr) produces too heavy outflows
  in weak field limit with only moderate Lorentz
  factors, G lt 2 (QSOs) ?
  extended to include radiation !
• GRMHD in strong field limit is still not solved
  (go inside horizon with boundary).
• Question of plasma injection is essential ? M
  87 requires relativistic component in the
  non-collimated regime (beyond MHD) !

31

• Jet formation will not be solved by GRMHD alone
  for at least two reasons
  ? disk-jet
  connection requires finite conductivity
  (reconnection e.g.) ?
  question of formation of non-thermal component is
  essential.
• ? Once the jet plasma goes through a shock
  (recollimation, pinch etc), electrons are highly
  relativistic, visible in IC as gamma-rays
• ? Jets never contain non-rel. electrons !
• ? VLBI-core is probably the location, where
  non-thermal electrons are formed.
• ? Not every VLBI-core must be this site ! GC
  and M 87 is probably magnetized disk.