General Relativistic MHD Simulations of Relativistic Jets in AGN

27 Pages·2012·3.72 MB·English

General Relativistic
MHD Simulations of
Relativistic Jets in AGN
Alexander (Sasha) Tchekhovskoy
Center for Theoretical Science Fellow
Princeton University
Ramesh Narayan, Harvard
Jon McKinney, Stanford-Maryland
Jets: Beautiful & Challenging
Cygnus A galaxy A
rtis
(radio, 6 and 20 cm) t’s
d
e
p
ic
tio
n
(C
h
a
n
d
ra
X
-ra
y
O
b
s
.)
M87 galaxy
109 solar mass
(radio, 20 cm)
black hole
Image courtesy of NRAO/AUI; R. Perley, C. Carilli & J. Dreher
109 solar mass
(radio, 7 mm) black hole
N
W R
a A
lke O/A
r U
et a I an
l. 2 d F
00 . O
8 w
e
n
1 light year
3000 light years
Alexander (S1a0s0h0a b)l aTckc hhoelke hraodviiskoy X-ray Astronomy in the next 50 years
Fundamental Questions
•
What sets the maximum power of jets?
•
Are jets powered by black holes or inner
regions of accretion disks?
•
How does jet power depend on BH spin?
•
Does accretion always spin up BHs to
high spins?
Alexander (Sasha) Tchekhovskoy X-ray Astronomy in the next 50 years
When Do We Observe Jets?
λ = L/L
edd
Radiatively-Inefficient
h/r 1
∼ (super-Eddington)
100%
τ 1
ULX/HLX and TDEs
￿
(see talks by Gladstone,
Middleton, Roberts, Farrell)
10%
h/r 1
Thin Disk
￿
τ 1
￿ (High/Soft or Thermal state)
1%
h/r 1
Radiatively-Inefficient
∼
(sub-Eddington)
τ 1
￿
(Low/Hard state)
Alexander (Sasha) Tchekhovskoy X-ray Astronomy in the next 50 years
When Do We Observe Jets?
λ = L/L
edd
Radiatively-Inefficient
h/r 1
∼ (super-Eddington)
100%
τ 1
ULX/HLX and TDEs
￿
(see talks by Gladstone,
Middleton, Roberts, Farrell)
10%
h/r 1
Thin Disk
￿
τ 1
￿ (High/Soft or Thermal state)
1%
h/r 1
Radiatively-Inefficient
∼
(sub-Eddington)
τ 1
￿
(Low/Hard state)
Alexander (Sasha) Tchekhovskoy X-ray Astronomy in the next 50 years
How Do Jets Work?
fi
e
l
d
li
n
e
Ω
t=0
Alexander (Sasha) Tchekhovskoy X-ray Astronomy in the next 50 years
How Do Jets Work?
2
B
ϕ
P =
8π
fi
e
l
d
li
n
e
Ω
t=t
t=0
1
Alexander (Sasha) Tchekhovskoy X-ray Astronomy in the next 50 years
How Do Jets Work?
B2 Field toroidally- B B
ϕ dominated ϕ z
￿
P =
8π
fi
e
l
d
li
n
e
Ω
t=t
t=t
t=0 2
1
Alexander (Sasha) Tchekhovskoy X-ray Astronomy in the next 50 years
How Do Jets Work?
B2 Field toroidally- B B
ϕ dominated ϕ z
￿
P =
8π
fi
e
l
d
li
n
e
Ω
t=t
t=t
t=0 2
1
Alexander (Sasha) Tchekhovskoy X-ray Astronomy in the next 50 years
How Do Jets Work?
B2 Field toroidally- B B
ϕ dominated ϕ z
￿
P =
8π
fi
e
l
d
li
n
e
Φ
Ω
t=t
t=t ac
t=0 2
1
Ω =
H
2r
H
Alexander (Sasha) Tchekhovskoy X-ray Astronomy in the next 50 years