Active galactic nuclei and blazars

Rodrigo Nemmen
Universidade de São Paulo
Active galactic
nuclei and
blazars

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Content of lectures
Broad overview: observations and theory of
active galactic nuclei (AGN)
Some emphasis on jetted AGNs (blazars) and
high-energy EM radiation

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Outline of lectures
1.Historical perspective
2.Black hole physics
3.Observed zoo
4.The ins of BHs: accretion
5.The outs: jets
6.Blazars

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References: theory
Physical processes in active galactic nuclei. Blandford, R. in
Active galactic nuclei Saas-Fee lecture notes
Black holes, white dwarfs and neutron stars. Shapiro, S. L. &
Teukolsky, S. A. (ch. 12, 14)
More details
Foundations of black hole accretion disk theory. Fragile, C. &
Abramowicz, M.
The Formation and Disruption of Black Hole Jets.
Contoupoulos, I. et al. (ch. 3, 6, 7)

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References: observations
Active galactic nuclei. Beckmann V. & Schrader, C.
An introduction to active galactic nuclei: Classiﬁcation and
uniﬁcation. New Ast. Rev. Tadhunter, C.
Relativistic jets in active galactic nuclei. ARAA. Blandford, R.
arXiv:1812.06025
Gamma-Ray Observations of Active Galactic Nuclei. ARAA.
Madejski, G. & Sikora, M.

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What is an active galactic nuclei?
Presence of accreting, supermassive
black hole at the center of a galaxy
AGN

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What physics is necessary?
general relativity
Kerr spacetime
(magneto)hydrodynamics
aka MHD

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What physics is necessary?
general relativistic MHD
(GRMHD)
at low accretion rates:
general relativistic kinetic theory
(GRK)

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Nature of AGNs: Accreting black holes
• enormous free energy
• can be extracted by particles/ﬁelds
Gravitational energy source

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Challenges

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AGNs: multifaceted phenomenon
(challenge #1)
Depending on how you
observe, AGNs look
diﬀerent
Appearance varies with
EM energy band (radio to
gamma-rays)

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AGNs: multifaceted phenomenon
(challenge #1)
Depending on how you
observe, AGNs look
diﬀerent
Appearance varies with
EM energy band (radio to
gamma-rays)
radio
jet!
thermal
UV!
dusty
torus!
hard
X-rays!
broad
lines!
rapid
variability!

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Quasar light curves imply Δtvar < 1 light-week
Size of system must satisfy size < cΔtvar
variability timescale
light-crossing radius
≈0.01 pc ~ 1000 AU

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Supermassive black holes (SMBHs) are
extremely small on the sky
Very hard to observe (challenge #2)
SMBH
Grapefruit
<10-4 pc
>10 kpc
event horizon size
galaxy size
~109

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AGNs easily outshine their host galaxies
(challenge #3)
this image: z ~ 0.2
dL
~ 1 Gpc
Hubble Space
Telescope
Bahcall+1997

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Steven Weinberg
When I received my undergraduate
degree — about a hundred years
ago — the physics literature
seemed to me a vast, unexplored ocean,
every part of which I had to chart before
beginning any research of my own. How
could I do anything without knowing
everything that had already been done?
Fortunately, in my first year of graduate
school, I had the good luck to fall into the
hands of senior physicists who insisted, over
my anxious objections, that I must start
doing research, and pick up what I needed
to know as I went along. It was sink or
swim. To my surprise, I found that this
works. I managed to get a quick PhD —
though when I got it I knew almost nothing
about physics. But I did learn one big
thing: that no one knows everything, and
you don’t have to.
Another lesson to be learned,to continue
work of many theoretical and experimental
physicists has been able to sort it out, and
put everything (well, almost everything)
together in a beautiful theory known as
the standard model.My advice is to go for the
messes — that’s where the action is.
My third piece of advice is probably the
hardest to take. It is to forgive yourself for
wasting time. Students are only asked to
solve problems that their professors (unless
unusually cruel) know to be solvable. In
addition,it doesn’t matter ifthe problems are
scientifically important — they have to be
solved to pass the course. But in the real
world,it’s very hard to know which problems
are important, and you never know whether
at a given moment in history a problem is
solvable. At the beginning of the twentieth
century,several leading physicists,including
Lorentz and Abraham, were trying to work
out a theory of the electron. This was partly
in order to understand why all attempts to
detect effects of Earth’s motion through the
to spending most of your time not being
creative, to being becalmed on the ocean of
scientific knowledge.
Finally, learn something about the history
ofscience,or at a minimum the history ofyour
own branch of science. The least important
reason for this is that the history may actually
be of some use to you in your own scientific
work. For instance, now and then scientists
are hampered by believing one of the over-
simplified models of science that have
been proposed by philosophers from Francis
Bacon to Thomas Kuhn and Karl Popper.
The best antidote to the philosophy of science
is a knowledge ofthe history ofscience.
More importantly, the history of science
can make your work seem more worthwhile
to you. As a scientist, you’re probably not
going to get rich. Your friends and relatives
Four golden lessons Scientist
Advice to students at the start of
their scientific careers.
(1979 Nobel Prize, Physics)
1. Learn to swim as you try
not to drown. — No one
knows everything, and you
don’t have to.
2. Aim for the rough water
(messes). — that’s where the
action is.
3. Forgive yourself for wasting
time.
4. Learn the history of
science. — at least of your
own ﬁeld.
2003 Nature
slide by Ken Nagamine

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Historical perspective on AGNs
1783: Newtonian “dark stars” predicted
1915: Einstein publishes his ﬁeld equation
1916: black hole solution derived from GR
1918: "curious straight ray" in galaxy M87, "connected
with the nucleus by a thin line of matter”—jets discovered
1963: strong optical point source found at 3C 273
nucleus—quasars discovered
Early 1990s: HST ﬁnds SMBHs at centers of nearby
galaxies
Late 1990s: stellar orbits at Galactic Center—
strongest BH case until 2015 (Sagittarius A*, 4×106 M⦿
)
Curtis 1918
Schmidt+1963
Ford+1994;
Harms+1994;
Ferrarese &
Ford 2004
Michell 1783
Schwarzschild 1916
Einstein 1915
Genzel &
Gillessen 2010

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Historical perspective on AGNs
Late 1990s, early 2000s: M-σ relation—SMBHs and host
galaxies are tightly connected
2000: SMBHs disturb thermodynamics of entire galaxy
clusters
2003: Sloan Digital Sky Survey (SDSS) ﬁnds >100k AGNs
2015: direct observation of gravitational waves from
stellar-mass BHs
2018a: 1st multimessenger observation from AGNs
(blazar TXS 0506+056)
2018b: GRAVITY resolves orbit at r = 7M (Sgr A*)
2019: EHT images event horizon (M87*)
McNamara+2000;
Fabian 2012
Abazajian+2003
IceCube, Fermi LAT
Collaborations
Magorrian+1998;
Kormendy & Ho 2013
Abbott+2015
Abuter+2018
EHTC

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(new technologies)∙(engineering)
= (new astronomical windows)
(new observations)×(grad students)
= paradigm change

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Pace of discovery is accelerating
Future: immense discovery space
awaiting
We entered 2nd golden age of
black hole (astro)physics
General lessons from history

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Black hole physics

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A general relativity primer
Einstein’s ﬁeld equation
Stress-energy
Ricci curvature Metric
Ricci
scalar
㱺
For a free particle:
Geodesic equation
Newtonian analogue Poisson equation
spacetime
curvature
= constant × matter-energy
R
μν
−
1
2
g
μν
R =
8πG
c4
T
μν
Solution to ﬁeld equation
gives
Line element
Metric

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What is a black hole? Remarkable
prediction of general relativity
Normal object Black hole
surface
event horizon
singularity
from black hole primer for
undergrads

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Event horizon: one-way membrane, matter/
energy can fall in, but nothing gets out
Black hole
event horizon
singularity
Region inside event horizon
causally cut-oﬀ from outside
RS =
2GM
c2
= 2.95
✓
M
M
◆
km
Radius of event horizon:
Schwarzschild radius
Gravitational radius:
R
g
≡
GM
c2 Useful scale

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Growth of black holes
If particles fall into the black hole
M increases
Schwarzschild radius RS = 2M increases
surface area increases

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Growth of black holes
If particles fall into the black hole
M increases
Schwarzschild radius RS = 2M increases
surface area increases
There is no limit to how big a BH can grow. From
astrophysics:
Mmin = 3.6 MSun
Mmax ~ 1010 MSun

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What is a black hole?
Once inside, nothing
escapes
Massive, compact
astronomical object:
gravity so strong that it
traps everything that falls
inside the event horizon

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Massive, compact
escapes
Father-in-law
Mother-
in-law

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Massive, compact
escapes

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A black hole has no hair
All black hole solutions of Einstein’s equation
completely characterized by only three externally
observable classical parameters:
Mass M
Spin: angular momentum J
Charge Q
J ≡ a
GM2
c
−1 ≤ a ≤ 1 spin parameter
No-hair theorem
All other information (“hair”=metaphor) disappears behind
the event horizon, therefore permanently inaccessible to
external observers

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Types of black holes
Mass M
Spin a
Charge Q
Schwarzschild spacetime
Kerr spacetime
Reissner–Nordström spacetime

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Schwarzschild black hole
Simplest black hole
Spherically symmetric spacetime
Relatively “easy” to handle analytically
ds2 = −
(
1 −
2M
r )
dt2 +
(
1 −
2M
r )
−1
dr2 + r2
(dθ2 + sin2 θdϕ2
)
Schwarzschild geometry in Schwarzschild coordinates

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Kerr black hole
Conservation of angular momentum leads to spinning
black holes
Rotational energy deforms spacetime → Kerr spacetime
Kerr metric considerably more complex than
Schwarzschild
ds2 = −
(
1 −
2Mr
ρ2 )
dt2 −
4Mar sin2 θ
ρ2
dϕdt +
ρ2
Δ
dr2 + ρ2dθ2
+
(
r2 + a2 +
2Mra2 sin2 θ
ρ2 )
sin2 θdϕ2
a ≡ J/M, ρ2 ≡ r2 + a2 cos2 θ, Δ ≡ r2 − 2Mr + a2
Boyer-Lindquist coords.

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Main parameters for astrophysical BHs
Gravity
Mass M
Spin a∗
Magnetic ﬂux Φ
Predict
Energy output in all forms (erg/s or LEdd)
(M⦿
= 2×1033 g)
(1 = max spin)
units
Accretion
Mass accretion rate (M⦿
/yr or )
˙
MEdd
AAACBXicdVDLSgMxFM3UV62vVpdugkVwIUNmbLXdFUVwI1SwD2iHksmkbWjmQZKplGHWfoVbXbkTt36HC//F9CGo6IELh3PuTe49bsSZVAi9G5ml5ZXVtex6bmNza3snX9htyjAWhDZIyEPRdrGknAW0oZjitB0Jin2X05Y7upj6rTEVkoXBrZpE1PHxIGB9RrDSUi9f6HqhSq7TXtIVPrz0vLSXLyIT2ZVyyYbItMuoalU1KSOrelqClolmKIIF6r38h36DxD4NFOFYyo6FIuUkWChGOE1z3VjSCJMRHtCOpgH2qTz2xiySM+oksytSeKhND/ZDoStQcKZ+H06wL+XEd3Wnj9VQ/vam4l9eJ1b9ipOwIIoVDcj8o37MoQrhNBLoMUGJ4hNNMBFMrw3JEAtMlA4up/P4Ohr+T5q2aZ2Y9k2pWDtfJJMF++AAHAELnIEauAJ10AAE3IEH8AiejHvj2XgxXuetGWMxswd+wHj7BMUUmPA=
˙
M
AAAB+XicdVDLSgMxFM3UV62vqks3wSK4kCEzbbHdFd24ESrYB7RDyWTSNjSTGZJMoQz9CLe6cidu/RoX/ovptIKKHggczrmHe3P8mDOlEXq3cmvrG5tb+e3Czu7e/kHx8KitokQS2iIRj2TXx4pyJmhLM81pN5YUhz6nHX9yvfA7UyoVi8S9nsXUC/FIsCEjWBup0w8ind7OB8USsut1VKlUIbKryHXdmiGo7NbqDnRslKEEVmgOih8mSZKQCk04VqrnoFh7KZaaEU7nhX6iaIzJBI9oz1CBQ6ougimLVUa9NLt8Ds+MGcBhJM0TGmbq93CKQ6VmoW8mQ6zH6re3EP/yeoke1ryUiTjRVJDlomHCoY7gogYYMEmJ5jNDMJHMnA3JGEtMtCmrYPr4+jT8n7Rd2ynb7l2l1LhaNZMHJ+AUnAMHXIIGuAFN0AIETMADeARPVmo9Wy/W63I0Z60yx+AHrLdP1nGUnQ==

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Main problem in BH
astrophysics
AGN(t) = f(M, a
*
,
·
M)

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Eddington luminosity LEdd
M
Luminosity L
from central object
photon
ﬁeld

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Eddington luminosity LEdd
p
e-
r
Luminosity L
from central object
When is the radiation strong enough to prevent
accretion of particles?
photon
ﬁeld

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F
rad
= F
g
Prad =
Frad
A
=
F
c
) Frad =
FA
c
) Frad =
L
4⇡r2
T
c
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
Solve this to get LEdd:
radiation force
on an electron
ﬂux
area

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F
rad
= F
g
Prad =
Frad
A
=
F
c
) Frad =
FA
c
) Frad =
L
4⇡r2
T
c
radiation force
on an electron
F
g
=
GM(m
e
+ m
p
)
r2
≈
GMm
p
r2
ﬂux
area
why?

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F
rad
= F
g
Prad =
Frad
A
=
F
c
) Frad =
FA
c
) Frad =
L
4⇡r2
T
c
radiation force
on an electron
F
g
=
GM(m
e
+ m
p
)
r2
≈
GMm
p
r2
L
Edd
=
4πGMm
p
c
σT
= 1.3 × 1038
(
M
M⊙ )
erg s−1
ﬂux
area
why?

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p
e-
M
photon
ﬁeld
Eddington luminosity: importance
L > L
Edd

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Eddington luminosity: importance
A system radiating at L > LEdd can halt mass
accretion due to strong radiation pressure
Roughly maximal luminosity that can be powered
by accretion (if spherical symmetry)
Useful luminosity unit in BH astrophysics

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Eddington accretion rate
• Assume an engine radiating at L = LEdd
• If it were converting mass to radiative
energy with eﬃciency η

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L
Edd
= η
·
M
Edd
c2 ⇒
·
M
Edd
≡
L
Edd
ηc2
usually η = 0.1

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L
Edd
= η
·
M
Edd
c2 ⇒
·
M
Edd
≡
L
Edd
ηc2
= 3
(
0.1
η ) (
M
108M⊙ )
M
⊙
yr−1
Useful accretion rate
unit in BH astrophysics
usually η = 0.1

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Eddington time tEdd
·
M =
dM
dt
=
·
M
Edd
⇒
dM
dt
=
M
tEdd
Assume BH accreting at Eddington rate
also known as Salpeter time tS

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Eddington time tEdd
·
M =
dM
dt
=
·
M
Edd
⇒
dM
dt
=
M
tEdd
Assume BH accreting at Eddington rate
t
Edd
≡
ηcσ
T
4πGmp
= 4 × 107
(
η
0.1 )
yr
Useful timescale
also known as Salpeter time tS

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Useful websites and apps for
grad students
arxiv.org
ui.adsabs.harvard.edu
sci-hub.tw
voxcharta.org
Find papers Manage papers
Mendeley, bibdesk,
Papers, Jabref

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Pro tips
Organize papers using convention:
1. Folders named after categories
2. Filename: author>
3. Use a desktop search app to ﬁnd (spotlight,
cerebro, albert)

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Important lengths
risco: Innermost stable circular orbit
from now on, G = c = 1
r
isco
= 6M for a
∗
= 0

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Misner, Thorne & Wheeler
Effective potential for orbits around a Schwarzschild black hole
E =
1
2 (
dr
dτ)
2
+ V
eff
V
eff
r/M
effective
potential
face-on view of accretion disk
innermost stable
circular orbit
6M
edge-on view

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Misner, Thorne & Wheeler
Effective potential for orbits around a Schwarzschild black hole
E =
1
2 (
dr
dτ)
2
+ V
eff
V
eff
r/M
effective
potential
innermost stable
circular orbit
risco

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Important radii
risco: Innermost stable circular orbit
from now on, G = c = 1
r
isco
= 6M for a
∗
= 0
rc: photon capture radius
also called photon sphere or photon ring
r
c
= 3M
seen from ∞
27M
apparent radius
for a
∗
= 0

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Schwarzschild radius
photon ring
light rays
https://www.codeproject.com/Articles/994466/Ray-Tracing-a-Black-Hole-in-Csharp

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Dependence of radii on BH spin
Bardeen+1972
a∗

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Dependence of radii on BH spin
Bardeen+1972
a∗
horizon
equator
photon capture
isco
+
-
-
+

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Important timescales
Light-crossing t
l
=
r
c
= 2
(
r
104M ) (
M
108M⊙ )
months
as a function of distance r from 108 M⦿
BH
Sound-crossing
t
s
=
r
cs
= 700
(
r
104M ) (
M
108M⊙ ) (
T
105K )
−1/2
years
Accretion
t
acc
=
r
vr
= 107
(
α
0.1 )
−4/5
(
r
104M)
5/4
(
M
108M⊙ )
3/2
(
·
M
0.1
·
MEdd
)
−3/10
years
~ viscous time
Free-fall t
ff
=
(
GM
2r3 )
−1/2
= 23
(
r
104M)
3/2
(
M
108M⊙ )
years
~ dynamical time

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Gravitational sphere of
inﬂuence of SMBHs
r
sph
≈
GM
σ2
= 5
(
M
108M⊙ ) (
σ
300 km s−1 )
−2
pc
stellar velocity
dispersion (bulge)

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Gravitational sphere of
inﬂuence of SMBHs
r
sph
≈
GM
σ2
= 5
(
M
108M⊙ ) (
σ
300 km s−1 )
−2
pc
stellar velocity
dispersion (bulge)
rS / rsph = 10-6
Some size ratios
rgal / rsph > 104
rbulge / rsph = 200

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Eﬃciency of release of free
energy from BH accretion disks
r → ∞
How much orbital energy lost by particle when it
disappears behind event horizon?
1st order estimate of Lacc

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How much orbital energy lost by one particle?
E
acc
= U(r → ∞) − U(r
surface
) gravitational
potential
energy
=
GMm
rsurface

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E
acc
= U(r → ∞) − U(r
surface
)
gravitational
potential
energy
=
GMm
rsurface
Energy lost by continuous inﬂow of particles?
·
m =
dm
dt
dE
acc
dt
=
GM ·
m
rsurface
⇒ L =
GM ·
m
rsurface

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E
acc
= U(r → ∞) − U(r
surface
)
gravitational
potential
energy
=
GMm
rsurface
Energy lost by continuous inﬂow of particle?
·
m =
dm
dt
dE
acc
dt
=
GM ·
m
rsurface
⇒ L =
GM ·
m
rsurface
Luminosity released from accretion
L = η ·
mc2 ⇒ η =
L
·
mc2
=
GM
rsurface
c2
maximized
for compact
objects

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For a Schwarzschild BH
η = 0.5 incorrect
Newtonian
value
Correct GR result
η = V
eff
(∞) − V
eff
(6M)
= − V
eff
(6M) =
1
18
= 0.06

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Itaipu Dam − 14 GW
⌘ =
mgh
mc2
= 10 14
✓
h
100 m
◆

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Nuclear fusion
⌘ = 0.008 ⇥ 0.1 ⇠ 8 ⇥ 10 4
Tsar bomba

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ISCO radius depends on the BH spin
a
*
= 0 a
*
= 0.998
Disk is:
hotter
larger surface area
higher velocities
edge-on view

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UO
aim
o 0.2 0.5 0.7 0.6 0.9 0.95 0.96 1
mO.
(3.12)
Fig.3.2. Efficiency of energy release by gas accreting through a thin accretion disk onto
a spinning black hole. The quantity plotted is 1 - em. as a function of the hole angular
η
Blandford 1990
a
*
η=0.42
at
a∗
=0.998

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Black hole spin leaves imprint
on accretion disk
Faster, hotter, brighter
but gravitational redshift

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AGN zoo

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Supermassive
106-1010 solar masses
one in every galactic nucleus
5-80 solar masses
~107 per galaxy
Stellar black holes
black holes

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Supermassive
106-1010 solar masses
one in every galactic nucleus
5-80 solar masses
~107 per galaxy
Stellar black holes
~1 Mpc ~100 kpc
Active galactic nuclei
Quasars
Radio
galaxies
black holes
Gamma-
ray bursts
Microquasars
1 pc = 3×1013 km
Blazars
Binary systems

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Phenomenology of active galactic nuclei
8 m VLT reveals a
um of the elliptical
mplication is that
cted in scattered
cases, spectropo-
ontrast of the scat-
m and narrow line
trum in polarized
en et al., 1999).
ons are static over
a Sy1). However,
ve only been pos-
od is short relative
07 to 108 yr). Thus
ons over their life-
nt over the short
e AGN are known
mescales of years
of NGC4151 and
een Sy1 and Sy2
and Perez, 1984;
nuclei have been
similar timescale
1996). By analogy
we must also be
the diversity in their properties, some of the most important in-
sights into the nature of AGN have been gained by considering
based on Tadhunter+08
Nuclear lum
inosity
Radio power
Broad / Narrow
lines

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8 m VLT reveals a
mplication is that
cted in scattered
cases, spectropo-
m and narrow line
trum in polarized
en et al., 1999).
ons are static over
a Sy1). However,
ve only been pos-
07 to 108 yr). Thus
nt over the short
e AGN are known
mescales of years
of NGC4151 and
een Sy1 and Sy2
and Perez, 1984;
nuclei have been
similar timescale
1996). By analogy
we must also be
Nuclear lum
inosity
Radio power
Broad / Narrow
lines
Type I Type II

View Slide

λ (Angstrom)
AGNs with and without broad emission
lines
BH’s gravity
accelerating the
gas to v>1000 km/s
but half of AGNs
show narrower
lines
Flux (arbitrary units)

View Slide

λ (Angstrom)
6.7. AGN uniﬁcation 139
Ionization cone
Radio jet
NLR clouds illuminated
by central source
Black hole accretion disk
And BLR
Clumpy dusty
torus
Type-II AGNs
Radio loud
Radio quiet
Type-I AGNs
Radio loud
Radio quiet
Blazars
Type I
Type II
Uniﬁed model of AGNs

View Slide

8 m VLT reveals a
mplication is that
cted in scattered
cases, spectropo-
m and narrow line
trum in polarized
en et al., 1999).
ons are static over
a Sy1). However,
ve only been pos-
07 to 108 yr). Thus
nt over the short
e AGN are known
mescales of years
of NGC4151 and
een Sy1 and Sy2
and Perez, 1984;
nuclei have been
similar timescale
1996). By analogy
we must also be
Nuclear lum
inosity
Radio power
Broad / Narrow
lines

View Slide

8 m VLT reveals a
mplication is that
cted in scattered
cases, spectropo-
m and narrow line
trum in polarized
en et al., 1999).
ons are static over
a Sy1). However,
ve only been pos-
07 to 108 yr). Thus
nt over the short
e AGN are known
mescales of years
of NGC4151 and
een Sy1 and Sy2
and Perez, 1984;
nuclei have been
similar timescale
1996). By analogy
we must also be
Nuclear lum
inosity
Radio power
Radio-quiet
Radio-loud
Radiogalaxies (FRI,
FRII)
radio-loud quasar
blazars (BL Lac, FSRQ)
Seyferts
Radio-quiet quasar

View Slide

8 m VLT reveals a
mplication is that
cted in scattered
cases, spectropo-
m and narrow line
trum in polarized
en et al., 1999).
ons are static over
a Sy1). However,
ve only been pos-
07 to 108 yr). Thus
nt over the short
e AGN are known
mescales of years
of NGC4151 and
een Sy1 and Sy2
and Perez, 1984;
nuclei have been
similar timescale
1996). By analogy
we must also be
Nuclear lum
inosity
Radio power
Radio-quiet
Radio-loud
10% of AGNs are
radio-loud

View Slide

8 m VLT reveals a
mplication is that
cted in scattered
cases, spectropo-
m and narrow line
trum in polarized
en et al., 1999).
ons are static over
a Sy1). However,
ve only been pos-
07 to 108 yr). Thus
nt over the short
e AGN are known
mescales of years
of NGC4151 and
een Sy1 and Sy2
and Perez, 1984;
nuclei have been
similar timescale
1996). By analogy
we must also be
Nuclear lum
inosity
Radio power
Broad / Narrow
lines

View Slide

8 m VLT reveals a
mplication is that
cted in scattered
cases, spectropo-
m and narrow line
trum in polarized
en et al., 1999).
ons are static over
a Sy1). However,
ve only been pos-
07 to 108 yr). Thus
nt over the short
e AGN are known
mescales of years
of NGC4151 and
een Sy1 and Sy2
and Perez, 1984;
nuclei have been
similar timescale
1996). By analogy
we must also be
Nuclear lum
inosity
Radio power
Broad / Narrow
lines
Low-
luminosity
AGNs

View Slide

8 m VLT reveals a
mplication is that
cted in scattered
cases, spectropo-
m and narrow line
trum in polarized
en et al., 1999).
ons are static over
a Sy1). However,
ve only been pos-
07 to 108 yr). Thus
nt over the short
e AGN are known
mescales of years
of NGC4151 and
een Sy1 and Sy2
and Perez, 1984;
nuclei have been
similar timescale
1996). By analogy
we must also be
Nuclear lum
inosity
Radio power
Broad / Narrow
lines
Low-
luminosity
AGNs
Quasars

View Slide

ken on the 8 m VLT reveals a
llar continuum of the elliptical
A further complication is that
may be detected in scattered
ight. In such cases, spectropo-
nhance the contrast of the scat-
ar continuum and narrow line
tic Sy1 spectrum in polarized
d, 1985; Cohen et al., 1999).
t classifications are static over
Sy1 always a Sy1). However,
ts of AGN have only been pos-
is time period is short relative
of AGN ($ 107 to 108 yr). Thus
e classifications over their life-
eing apparent over the short
n fact, some AGN are known
hanges on timescales of years
the cases of NGC4151 and
anged between Sy1 and Sy2
ars (Penston and Perez, 1984;
me LINER nuclei have been
eristics on a similar timescale
ower et al., 1996). By analogy
ry systems, we must also be
?
˙
M
/ ˙
M
E
dd
orientation
orientation
TOR = f( ˙
M)
Nuclear lum
inosity
Radio power
Broad /
Narrow lines
spin a
magnetic
flux Φbh

View Slide

Issues with the AGN uniﬁcation
proposal

View Slide

Current compilation of spin constraints
D

0.(.0h)

Many rapidly spinning BHs. More
slowly spinning population may
emerge at higher masses.
Reynolds (2013; arXiv:1302.3260)
… also see Sesana et al. (2014)
BH spin distribution from X-ray
spectroscopy (only radio quiet AGN)
106 107 108 109
Black hole mass (MSun)
cf. also Brenneman+13; King+13
Reynolds+13
Spin a
XMM-Newton + Suzaku
Why no jets?

View Slide

Sikora+2007
log Lbol/LEdd
(radio
loudness)
BLRG
RL quasars
FR I
PG
quasars
Sy + LINER
The BH knows about its host galaxy
Radio louds
Radio quiets

View Slide

log Lbol/LEdd
(radio
loudness)
Radio quiets
ellipticals
spirals
spin~1?
spin<0.3 ?
Wilson & Colbert 95
Moderski+96,98
Tchekhovskoy+10
Radio louds
Sikora+2007
The BH knows about its host galaxy

View Slide

Basic equations for BH
accretion

View Slide

D⇢
Dt
+ ⇢r · v = 0
⇢
Dv
Dt
= rp ⇢r + r · T
⇢
D(e/⇢)
Dt
= pr · v + T2/µ
Conservation
of
Mass
Momentum
Energy
D⇢
Dt
+ ⇢r · v = 0
⇢
Dv
Dt
= rp ⇢r + r · T
⇢
D(e/⇢)
Dt
= pr · v + T2/µ r · Frad
r · q
D⇢
Dt
+ ⇢r · v = 0
⇢
Dv
Dt
= rp ⇢r + r · T
⇢
D(e/⇢)
Dt
= pr · v + T2/µ r · Frad
r · q
Equations of Newtonian hydrodynamics
Plus:
equation of state
opacity description
viscosity
taken from accretion lecture at “bh
gastrophysics” course
Rate of change
“following the ﬂuid”

View Slide

General Relativistic Hydrodynamics
• The general relativistic hydrodynamics equations are obtained from the local
conservation laws of the stress-energy tensor, Tµν (the Bianchi identities), and of the
matter current density Jµ (the continuity equation):
rµ(⇢uµ) = 0
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
rµTµ⌫ = 0
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
equations of motion
(µ = 0, ..., 3)
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
: covariant derivative associated with the four
dimensional spacetime metric
rµ
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
gµ⌫
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
• The density current is given by Jµ = ⇢uµ
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
is the ﬂuid 4-velocity and is the rest-mass density in a locally inertial reference
frame.
uµ
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
⇢
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
slide: Yosuke Mizuno

View Slide

rµ(⇢uµ) = 0
rµTµ⌫ = 0
• GRHD equations + Maxwell equations
rµ
⇤Fµ⌫ = 0
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
where Fµν, Faraday tensor may be constructed from electric and magnetic ﬁelds Eα, Bα as
measured in a generic frame as
Fµ⌫ = UµE⌫ U⌫Eµ ( g) 1/2⌘µ⌫ U B
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
where ηµνλδ: the fully-antisymmetric symbol and g : determinant of 4-
metric
• The dual Faraday tensor is
⇤Fµ⌫ = UµB⌫ U⌫Bµ ( g) 1/2⌘µ⌫ U E
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
• Ideal MHD limit Fµ⌫u⌫ = 0
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
Jµ = ⇢quµ + Fµ⌫u⌫
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
! 1
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
U↵
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
General relativistic magnetohydrodynamics
slide: Yosuke Mizuno

View Slide

Accretion ﬂow states

View Slide

Thermal sta
(NLS1s?)
Intermediat
(Quasars, Se
M
·
a
Simple description of an accretion disk
·
M/
·
M
Edd
mass accretion rate
h /r
disk thickness
·
M = 4πr2ρv
r
mass accr. rate related to gas density

View Slide

t
cool
≪ t
acc
h/r ⇠ 1
–8
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
(Quasars, Seyferts?)
Hard state
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*)
M
·
0
log (L/L
Edd
)
a b
·
M/
·
M
Edd
1
RIAFs
h/r ⌧ 1
Thin disks
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
M
·
log (L/L
Edd
)
a b
–8
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*) 0
Figure 7
(a) Schematic diagram showing the configuration of the accretion flow in different
accretion rate ˙
MBH
(panel adapted from Esin et al. 1997, Narayan & McClintock
in parentheses. Red triangles indicate the hot accretion flow, whereas thick black h
transition radius Rtr where the thin disk is truncated becomes smaller with increas
truncated, and its inner edge is located at the ISCO. (b) Plot of the Eddington-scal
from observations. The transition radii were estimated by modeling spectra of ind
Yuan & Narayan 2004). Abbreviations: AGN, active galactic nuclei; BHB, black h
LLAGN, low-luminosity active galactic nuclei.
h/r ⇠ 1
0.01
then move on and describe consequence for efficiency
q
adv
≫ q
−
q
adv
≫ q
−
Super-Eddington
q
−
≫ q
adv
Unified theory of black hole accretion flows
L/L
Edd

View Slide

t
cool
≫ t
acc
h/r ⌧ 1
Thin disks
·
M/
·
M
Edd
1
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
M
·
log (L/L
Edd
)
a b
–8
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*) 0
Figure 7
accretion rate ˙
MBH
h/r ⇠ 1
0.01
then move on and describe consequence for efficiency
q
adv
≫ q
−
q
adv
≫ q
−
Super-Eddington
h/r ⇠ 1
–8
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*)
M
·
0
log (L/L
Edd
)
a b
RIAFs
radiatively inefficient accretion flow
L/L
Edd

View Slide

h/r ⇠ 1
h/r ⌧ 1
Thin disks
–8
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*)
M
·
0
log (L/L
Edd
)
a b
·
M/
·
M
Edd
1
RIAFs
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
M
·
log (L/L
Edd
)
a b
–8
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*) 0
Figure 7
accretion rate ˙
MBH
h/r ⇠ 1
0.01
q
adv
≫ q
−
q
adv
≫ q
−
Super-Eddington

View Slide

h/r ⇠ 1
h/r ⌧ 1
Thin disks
–8
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*)
M
·
0
log (L/L
Edd
)
a b
·
M/
·
M
Edd
1
RIAFs
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
M
·
log (L/L
Edd
)
a b
0.01
q
adv
≫ q
−
–8
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*) 0
Figure 7
accretion rate ˙
MBH
h/r ⇠ 1
Super-Eddington
Adapted from Yuan & Narayan 2014, ARA&A
t
diﬀusion
≫ t
acc
photon

View Slide

h/r ⇠ 1
h/r ⌧ 1
Adapted from Yuan & Narayan 2014, ARA&A
Thin disks
–8
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*)
M
·
0
log (L/L
Edd
)
a b
·
M/
·
M
Edd
1
RIAFs
–6
–4
–2
0
Brig
C
Thermal state
(NLS1s?)
Intermediate state?
Hard state
(LLAGNs, Seyferts)
M
·
log (L/L
Edd
)
a b
–8
(LLAGNs, Seyferts)
Quiescent state
(LLAGNs, Sgr A*) 0
Figure 7
accretion rate ˙
MBH
h/r ⇠ 1
0.01
Super-Eddington
radiative eﬃciency
η ≪ 0.1
η = 0.06 − 0.4
η ≪ 0.1
L/L
Edd

View Slide

thin or thick. In thin disks, most of the mass
supplied at large radii reaches the central black
hole. By contrast, in thick disks, very little of the
supplied mass ends up accreting into the hole.
Instead, most of the mass circulates in convective
motions (33, 34) or is driven away in an unbound
outflow (35, 36). This in turn causes the
amount of radiation from the accretion flow to
decrease drastically. Because the fate of sup-
plied matter depends so strongly on the mode
of accretion (thin versus thick), it is likely
that bright accreting black holes occupy a
Jet
Coronal envelope
Inner torus
Main disk body
KDP
30
20
10
10
20
0
–10
1
SNE, GRB
Radiation–trapped
Bright XRBs, AGN
Faint XRBs, AGN
2
2 3
log R (RS
)
log R (km)
log M (MEdd
)
log M (g s–1)
Regimes of
BH accretion
Super-Eddington,
radiation-trapped
TDE, AGN?
Near-Eddington
Sub-Eddington
om the accretion flow to
Because the fate of sup-
so strongly on the mode
rsus thick), it is likely
black holes occupy a
Main disk body
KDP
30
20
10
0
SNE, GRB
Radiation–trapped
Bright XRBs, AGN
Faint XRBs, AGN
log M (MEdd
)
log M (g s–1)
Main disk body
KDP
20
10
0
–10
1
Radiation–trapped
Bright XRBs, AGN
Faint XRBs, AGN
2
log R (RS
)
log M (MEdd
)
log M (g s–1)
the central black
s, very little of the
ng into the hole.
ates in convective
way in an unbound
turn causes the
accretion flow to
the fate of sup-
ngly on the mode
ick), it is likely
holes occupy a
KDP
30
10
20
SNE, GRB
Radiation–trapped
2 3
log R (km)
log M (MEdd
)
log M (g s–1)
Adapted from Narayan &
Quataert 2005
Faint XRBs, low-
luminosity AGNs
Bright XRB, quasars, Seyferts
log R (pc)
-4 -5
?
?
slide from BASS ESO 2018
talk

View Slide

Jets
slides in this section come from jets
lecture in “BH gastrophysics” course

View Slide

Hercules A
Black holes produce relativistic jets of
particles
Size of the
galaxy

View Slide

Hercules A
3C 31
~1 Mpc ~100 kpc
M87
Cosmic
particle
accelerators!
Black holes produce relativistic jets of
particles
Huge powers (enough to
unbind a galaxy)
Aligned over long periods
(millions of years)

View Slide

How are relativistic jets
produced by black holes?
Conjecture: from spinning black holes
Huge free energy
Stable gyroscopes
Growing evidence that this is correct
Theory/simulations
Observations (?)

View Slide

https://www.youtube.com/watch?v=9MHuhcFQsBg
Penrose process: Spinning black hole has free
energy that can be extracted
Rotational energy of spacetime
(frame dragging)
Thought experiment by Penrose that
demonstrates the principle, probably
not important in astrophysics
But magnetized accretion disks is
promising
Penrose 1969
Ruﬃni & Wilson 1975; Blandford & Znajek 1977

View Slide

Need a natural mechanism to
accelerate particles from compact
objects

View Slide

How jets are formed
large scale B + accretion
+ rotation
Semenov+2004, Science
magnetic
ﬂux tube
ergosphere
Requirements
v
⊵
spinning
black hole

View Slide

How jets are formed
+ rotation
Requirements
P =
B2
8⇡
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

View Slide

How jets are formed
+ rotation
Requirements
environment
radiation
GR
Lense-Thirring precession
Complications for theory
Blandford-Znajek
mechanism:
Jet power
rotation frequency
magnetic ﬂux
∝(ΦΩ)2 ∼
(
a
M
Φ
BH)
2
∼ a2
·
Mc2
Jet

View Slide

Kudos to Alice Harding (NASA GSFC) https://www.youtube.com/watch?v=R173dLIktsw
How to make a black hole jet at home:
Homopolar generator

View Slide

Best way of producing relativistic jets
Compact object accreting highly magnetized gas
magnetized
accretion ﬂow
Such conditions are natural outcomes of stellar deaths and easily
produced around black holes

View Slide

Basic facts about jets
Highly magnetized
β =
P
gas
Pmag
< 0.1
N
m
s
T
th
r
in
la
a
in
u
ti
s
o
U
strong
synchrotron
radiation
ν
c
∼ γ2B MHz
expect to see in radio

View Slide

Highly magnetized
β =
P
gas
Pmag
< 0.1
Relativistic
Γ ∼ a few − 100 v > 0.9c
AGNs GRBs
bulk
Lorentz
factor

View Slide

synchrotron emitting
electron
in the comoving frame
of the plasma

View Slide

shall Cohe
discovered
These are p
that is, wh
any misalig
jets associa
the emissio
with the fa
degrees or
One does n
less they ex
radio sour
v= 0.94c
comoving
frame
ments of s
shall Cohe
discovered
These are
that is, wh
any misali
jets associa
the emissio
with the fa
degrees or
One does
less they ex
v= 0.5c
ments of sm
shall Cohe
discovered
These are p
that is, wh
any misalig
jets associa
the emissio
with the fa
degrees or
One does n
less they ex
v= 0.75c
shall Cohe
discovered
These are
that is, wh
any misali
jets associa
the emissio
with the fa
degrees or
One does
less they ex
radio sour
v= 0.98c
observer’s frame

View Slide

Highly magnetized
β =
P
gas
Pmag
< 0.1
Relativistic
Γ ∼ a few − 100 v > 0.9c
Beamed: most radiated power along the propagation
direction, skewed towards high frequency
relativistic
aberration
Doppler shift

View Slide

neutrinos, cosmic rays
maybe show Feynman diagrams
Collimated
Highly magnetized
β =
P
gas
Pmag
< 0.1
Relativistic
Γ ∼ a few − 100 v > 0.9c
Beamed: most radiated power along the propagation
direction
θ
j
< 10∘
collimation
half-angle
θ
j

View Slide

Blazars
slides from my talk “jets and uniﬁed
model”

View Slide

Launching of Active Galactic Nuclei Jets
19
toward the polar regions as they move away from the BH. The group of field lines
highlighted in green connects to the BH and makes up the twin polar jets. The jet
field lines extract BH rotational energy and carry it away to large distances. These
field lines have little to no gas attached to them and are therefore highly magnetized
(since disk gas cannot cross magnetic field lines and is thus blocked from getting
to the polar region, the jet field lines either drain the gas to the BH or fling the gas
Fig. 9 [Panel (a)]: A 3D rendering of our MAD a = 0.99 model at t = 27,015rg
/c (i.e., the same
time as Fig. 8d). Dynamically-important magnetic fields are twisted by the rotation of a BH (too
small to be seen in the image) at the center of an accretion disk. The azimuthal magnetic field
component clearly dominates the jet structure. Density is shown with color: disk body is shown
ith yellow and jets with cyan-blue color; we show jet magnetic field lines with cyan bands. The
s approximately 300rg
⇥800rg
. [Panel (b)]: Vertical slice through our MAD a = 0.99
e and azimuth over the period, 25,000rg
/c  t  35,000rg
/c. Ordered,
fields remove the angular momentum from the accreting gas
pinning BH (a = 0.99). Gray filled circle shows the
s, and gray dashed lines indicate density
of the time-average magnetic
s is also seen from
nd with
Jet sim.: Tchekhovskoy
The difference between blazars and
radio galaxies is orientation
Blazar
Radio galaxy
Radio galaxy Rad

View Slide

Beyond orientation: Radio loud AGNs
have different states of accretion flow
FR I
FR II
Radio galaxy
morphology
BL Lac
FSRQ
flux
flux
ADAF
thin disk
Blazar spectral type
Wavelength (A)
Wavelength (A)
Low power,
weak lines
High power,
broad lines,
UV bump
Accretion mode
torus disappears?

View Slide

Synchrotron
emission
Inverse Compton
Isotropic Radio
Emission from
Slowed Plasma in
the Lobes
E. Meyer+2011
log(⌫/Hz)
log(⌫L⌫/erg s 1)
dp" = Pdx"
As a consequence, P is a scalar invariant. We therefor
relativistic generalisation of equation (2.3)for which
choice is
2e2 dp" dp,.
P=--<-->
dr dr
where r denotes the proper time. Rewriting this eq
(3 = v/ c, we obtain
For synchrotron radiation, the particle energy is
Equation(2.6)can be re-written in the convenient for
2 2 (B2)
P = 2aTCf (31. 871"
Synchrotron power:
Opt. thin
synchrotron
Synchrotron
self-absorption
Blazars: observing beamed
power of the relativistic jet

View Slide

Blazar zoo: the “blazar sequence”
Fossati+1998; Donato+2001
Ghisellini 11
Swift / BAT Fermi / LAT
Integral
FSRQs
BL Lacs

View Slide

Ghisellini 11
Integral
FSRQs
BL Lacs
Line strength
˙
M/ ˙
MEdd

View Slide

Ghisellini 11
Integral
FSRQs
BL Lacs
FR II
FR I
Continuous?
Discontinuity

View Slide

Next Monday: Fabio Cafardo’s
lecture on Fermi LAT observations

View Slide

GRMHD simulation of a jetted AGN
https://youtu.be/TdZdqfD0LTI

View Slide

Observing the supermassive black hole
M87* in virtual reality
https://www.youtube.com/watch?v=bWg6vaf5WXw

View Slide

EM radiation:
radio, infrared, optical, X-rays, gamma-rays
neutrinos,
cosmic rays
AGNs: Powerful EM radiators,
particle accelerators

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EM radiation:
radio, infrared, optical, X-rays, gamma-rays
neutrinos,
cosmic rays
Giant Magellan Telescope ELT LSST
Cherenkov Telescope Array SKA
IceCube Observatory
AGNs: Powerful EM radiators,
particle accelerators
LISA
GWs
Athena

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The future of AGN
astrophysics is
bright!
You can be part of this!
blackholegroup.org

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Github
Twitter
Web
E-mail
Bitbucket
Facebook
Group
ﬁgshare
[email protected]
rodrigonemmen.com
@nemmen
rsnemmen
facebook.com/rodrigonemmen
nemmen
blackholegroup.org
bit.ly/2fax2cT

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Active galactic nuclei and blazars

Active galactic nuclei and blazars

Rodrigo Nemmen

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