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AGN-induced feedback
in young, radio loud AGN
Joanna Holt
Leiden Observatory, Leiden University,
The Netherlands
Clive Tadhunter (Sheffield, UK), Raffaella Morganti (ASTRON, The Netherlands),
Bjorn Emonts (CSIRO, Australia)
Joanna Holt
13th October 2010, Kathmandu, Nepal
Introduction
activity & galaxy evolution
what is AGN-induced feedback? and why do we care?
compact (young) radio sources
what are they? and how do they fit in?
outflows in young radio sources
prevelance, driving mechanisms & impact
case study: PKS1345+12
summary & conclusions
Joanna Holt
13th October 2010, Kathmandu, Nepal
major merger(injection of large amounts of
material into nuclear regions)
‘fuel’ (ISM) is blown out
of galaxy
trigger AGN & major
starburst
AGN drives powerful
winds (shedding the natal
cocoon & revealing the
quasar)
BH grows rapidly through accretion(much of this phase hidden by natal cocoon;
accretion possibly close to Eddington rate)
Activity and galaxy evolution
[most models currently require 5-
10% Lbol although recent paper by
Hopkins proposes 10x less]
‘quasar mode’
eventually activity &
star formation cease
Urry & Padovani (1995)
Joanna Holt
13th October 2010, Kathmandu, Nepal
major merger(injection of large amounts of
material into nuclear regions)
‘fuel’ (ISM) is blown out
of galaxy
trigger AGN & major
starburst
AGN drives powerful
winds (shedding the natal
cocoon & revealing the
quasar)
BH grows rapidly through accretion(much of this phase hidden by natal cocoon;
accretion possibly close to Eddington rate)
Activity and galaxy evolution
[most models currently require 5-
10% Lbol although recent paper by
Hopkins proposes 10x less]
‘quasar mode’
eventually activity &
star formation cease
TRIGGERING
FEEDBACK
Joanna Holt
13th October 2010, Kathmandu, Nepal
major merger(injection of large amounts of
material into nuclear regions)
‘fuel’ (ISM) is blown out
of galaxy
trigger AGN & major
starburst
eventually activity &
star formation cease
AGN drives powerful
winds (shedding the natal
cocoon & revealing the
quasar)
BH grows rapidly through accretion(much of this phase hidden by natal cocoon;
accretion possibly close to Eddington rate)
Activity and galaxy evolution
[most models currently require 5-
10% Lbol although recent paper by
Hopkins proposes 10x less]
‘quasar mode’
TRIGGERING
FEEDBACK
Joanna Holt
13th October 2010, Kathmandu, Nepal
Large-scale classical
doubles ( 102-103 kpc )
Compact Steep Spectrum
(CSS; D < 15 kpc )
Gigahertz Peaked Spectrum (GPS;
D < 1 kpc )
compact = young (e.g. Fanti et al. 1995)
tdyn ~ 102-103 yrs (e.g. Owsianik et al. 1998)
tsp < 104 yrs (e.g. Murgia et al. 1999)
What are compact radio sources?
Joanna Holt
13th October 2010, Kathmandu, Nepal
What are compact radio sources?
young radio sources
dense ISM
small scale radio jets
ideal for studying
impact of activity on host galaxy
mechanical AGN feedback (outflows)
Joanna Holt
13th October 2010, Kathmandu, Nepal
What are compact radio sources?
young radio sources
dense ISM
small scale radio jets
ideal for studying
impact of activity on host galaxy
mechanical AGN feedback (outflows)
compact radio sources are
beacons identifying young,
recently triggered AGN
Joanna Holt
13th October 2010, Kathmandu, Nepal
Outflows in compact radio sources
[O II] [O III]
Hβ
Hα/[N II]
[S II][O I]
WHT/ISIS spectrum of PKS 1345+12
•extended emission
up to 20kpc
highly broadened lines with
strong blue asymmetries
NLR
NOT ‘black hole’ kick
Holt et al. 2003
Joanna Holt
13th October 2010, Kathmandu, Nepal
extended emission
up to 20kpc
highly broadened lines with
strong blue asymmetries
NARROW LINE REGION
Outflows in compact radio sources
[O II] [O III]
Hβ
Hα/[N II]
[S II][O I]
WHT/ISIS spectrum of PKS 1345+12
Holt et al. 2003
narrow:
FWHM ~ 350 km s-1
intermediate:
FWHM ~ 1200 km s-1
broad:
FWHM ~ 2000 km s-1
nuclear aperture
same model
for all lines
Joanna Holt
13th October 2010, Kathmandu, Nepal
WHT/ISIS spectrum of PKS 1345+12
Outflows in compact radio sources
[O II] [O III]
Hβ
Hα/[N II]
[S II][O I]
extended emission
up to 20kpc
highly broadened lines with
strong blue asymmetries
NLR
NOT ‘black hole’ kick
Holt et al. 2003
Joanna Holt
13th October 2010, Kathmandu, Nepal
11/14 sources show evidence for fast nuclear
outflows
systemic-broadest
size is important
smaller sources = higher velocities
Outflows in compact radio sources
Holt et al. 2008
Compact radio sources (this sample)
extended radio sources (Taylor 2004)extended radio sources (Taylor 2004)
compact radio sources (this sample)
Joanna Holt
13th October 2010, Kathmandu, Nepal
fast outflows are observed in young radio-
loud AGNwhat drives them?
how important are they?
Joanna Holt
13th October 2010, Kathmandu, Nepal
What drives the outflows?3 possible driving mechanisms:
AGN-driven winds (Balsara & Krolick 1993)
starburst driven superwinds (Heckman et al. 1990)
expanding radio jet (Bicknell et al. 1997)
Joanna Holt
13th October 2010, Kathmandu, Nepal
What drives the outflows?3 possible driving mechanisms:
AGN-driven winds (Balsara & Krolick 1993)
starburst driven superwinds (Heckman et al. 1990)
expanding radio jet (Bicknell et al. 1997)
HST imaging: rules out galaxy wide starburst driven winds
PKS 1345+12: [O III] region ~160pc
can not distinguish between jets and winds
aa
Batcheldor et al. 2007
HST/ACS HRC
continuum subtracted [O
III] image
x - NIR core position
advantage of emission lines
over absorption lines is that
the outflowing regions can be
imaged directly
Joanna Holt
13th October 2010, Kathmandu, Nepal
What drives the outflows?
3 possible driving mechanisms:
AGN-driven winds (Balsara & Krolick 1993)
starburst driven superwinds (Heckman et al. 1990)
expanding radio jet (Bicknell et al. 1997)
HST imaging: rules out galaxy wide starburst driven winds
PKS 1345+12: [O III] region ~160pc
can not distinguish between jets and winds
Batcheldor et al. 2007
thick contours: [O III] emission
thin contours: 1.3GHz VLBI radio map from Morganti et al. (2004)
Joanna Holt
13th October 2010, Kathmandu, Nepal
What drives the outflows?
3 possible driving mechanisms:
AGN-driven winds (Balsara & Krolick 1993)
starburst driven superwinds (Heckman et al. 1990)
expanding radio jet (Bicknell et al. 1997)
HST imaging: rules out galaxy wide starburst driven winds
PKS 1345+12: [O III] region ~160pc
can not distinguish between jets and winds
diagnostic diagrams ambiguous
Joanna Holt
13th October 2010, Kathmandu, Nepal
What drives the outflows?3 possible driving mechanisms:
AGN-driven winds (Balsara & Krolick 1993)
starburst driven superwinds (Heckman et al. 1990)
expanding radio jet (Bicknell et al. 1997)
HST imaging: rules out galaxy wide starburst driven winds
PKS 1345+12: [O III] region ~160pc
can not distinguish between jets and winds
diagnostic diagrams ambiguous
kinematics/density/temperature suggest radio-jet interactions
jet-interactions further implied from radio-optical alignment
Joanna Holt
13th October 2010, Kathmandu, Nepal
What drives the outflows?
3C 49
3C 268.3
3C 3053C 303.1
3C 124CSS sources
strong R-O alignment
at all redshifts
e.g. de Vries et al. 1997,1999; Axon et al. (2000); Privon et al. (2008)
c.f. extended sources: only at z > 0.6
radio-optical alignment now been observed in a few 10s of sources
Joanna Holt
13th October 2010, Kathmandu, Nepal
What drives the outflows?
Tadhunter et al. 2001
cartoon model for PKS 1549-79
Joanna Holt
13th October 2010, Kathmandu, Nepal
What drives the outflows?
jet-driven outflows! ?
uncertainties preclude confident statements
recent discoveries of similar line profiles/outflows in ULIRGs (e.g. Spoon & Holt, 2009)
many (especially extreme) compact radio sources can also be classified
as other types of AGN e.g.
ULIRGs (e.g. PKS 1345+12)
NLS1 (e.g. PKS 1549-79; Holt et al. 2006)
powerful quasars
rapidly evolving proto-quasars (e.g. PKS 1549-79; Holt et al. 2006)
Joanna Holt
13th October 2010, Kathmandu, Nepal
most important parameters for studying AGN feedback:
mass outflow rates & bulk kinetic powers
enable comparison with available accretion energy (E/Lbol)
mass outflow rate proportional to L(Hβ), outflow velocity, density etc.......:
PKS1345+12: impact of the outflow
●
M L(Hβ) υout
●∝ne
E M(υ2 + FWHM2)●∝●and
Joanna Holt
13th October 2010, Kathmandu, Nepal
most important parameters for studying AGN feedback:
mass outflow rates & bulk kinetic powers
enable comparison with available accretion energy (E/Lbol)
mass outflow rate proportional to L(Hβ), outflow velocity, density etc.......:
• problems deriving density from [S II]6716/6731
• until recently, were only estimates for 2 sources: PKS 1345+12 (Holt 2005) & PKS 1549-79 (Holt et al. 2006)
PKS1345+12: impact of the outflow
●
M L(Hβ) υout
●∝ne
E M(υ2 + FWHM2)●∝●and
Joanna Holt
13th October 2010, Kathmandu, Nepal
M L(Hβ) υout
●∝ne
most important parameters for studying AGN feedback:
mass outflow rates & bulk kinetic powers
enable comparison with available accretion energy (E/Lbol)
mass outflow rate proportional to L(Hβ), outflow velocity, density etc.......:
• problems deriving density from [S II]6716/6731
• until recently, were only estimates for 2 sources: PKS 1345+12 (Holt 2005) & PKS 1549-79 (Holt et al. 2006)
E M(υ2 + FWHM2)●∝●and
PKS1345+12: impact of the outflow
●
Holt et al. 2003
nuclear aperture
[S II]6716,6731
Joanna Holt
13th October 2010, Kathmandu, Nepal
PKS1345+12: impact of the outflow
●
Holt et al. 2010
VLT/FORS2 spectrum of PKS 1345+12
deeper & further into the near-IR than
WHT/ISIS spectrum
nuclear aperture
Joanna Holt
13th October 2010, Kathmandu, Nepal
PKS1345+12: impact of the outflow
●
VLT/FORS2 spectrum of PKS 1345+12
deeper & further into the near-IR than
WHT/ISIS spectrum
nuclear aperture Holt et al. 2010
Joanna Holt
13th October 2010, Kathmandu, Nepal
PKS1345+12: impact of the outflow
●
VLT/FORS2 spectrum of PKS 1345+12
deeper & further into the near-IR than
WHT/ISIS spectrum
nuclear aperture
Holt et al. 2010
nuclear aperture
Holt et al. 2010
Joanna Holt
13th October 2010, Kathmandu, Nepal
PKS1345+12: impact of the outflow
simple-slab AGN
photoionisation
models
top cluster: ne = 100 cm-3,
various U and α
rest: density sequences (ne =
102-105 cm-3) for U = 0.005 and
α = -1.5 and E(B-V) = 0-1
(F∝α)
nuclear aperture
Holt et al. 2010
Joanna Holt
13th October 2010, Kathmandu, Nepal
PKS1345+12: impact of the outflow
method advantagesnuclear aperture
blends as complex as
[S II]6716,6731 but ratio
does not rely on ratios
within a blend, only on
total flux per component
sensitive to higher
densities
insensitive to details of
ionisation model
correct for reddening
simultaneously
Holt et al. 2010
Joanna Holt
13th October 2010, Kathmandu, Nepal
outflow velocities: ~400 kms-1 (intermediate); ~2000 km s-1 (broad)
L(Hβ): ~1042 erg s-1 (intermediate); ~1041 erg s-1 (broad)
density: ~104 cm-3 (intermediate); ~105 cm-3 (broad)
• total mass outflow rate: 8 M yr-1
• total kinetic power: 3.4 x 1042 erg s-1
PKS1345+12: impact of the outflow
Holt et al. 2010
Joanna Holt
13th October 2010, Kathmandu, Nepal
outflow velocities: ~400 kms-1 (intermediate); ~2000 km s-1 (broad)
L(Hβ): ~1042 erg s-1 (intermediate); ~1041 erg s-1 (broad)
density: ~104 cm-3 (intermediate); ~105 cm-3 (broad)
• total mass outflow rate: 8 M yr-1
• total kinetic power: 3.4 x 1042 erg s-1
PKS1345+12: impact of the outflow
warm outflow only accounts for
a small fraction of the available
accretion power
E
Lbol
●
= 1.3 x 10-3 [0.13% of available accretion power]
Holt et al. 2010
Joanna Holt
13th October 2010, Kathmandu, Nepal
models also predict AGN should remove all of the warm/cool gas from the
central regions
assuming that PKS 1345+12 has:
total mass of 1011 M
total gas mass of 1010 M within 5 kpc
[conservative assumptions for ULIRGs]
PKS1345+12: impact of the outflow
Ebind ~ (G Mgas Mtotal) / Rgas ~ 1058 erg
Holt et al. 2010
Joanna Holt
13th October 2010, Kathmandu, Nepal
models also predict AGN should remove all of the warm/cool gas from the
central regions
assuming that PKS 1345+12 has:
total mass of 1011 M
total gas mass of 1010 M within 5 kpc
[conservative assumptions for ULIRGs]
• warm outflow deposits ~1056 erg in 107 year
PKS1345+12: impact of the outflow
Ebind ~ (G Mgas Mtotal) / Rgas ~ 1058 erg
Holt et al. 2010
warm outflow not currently
capable of clearing nuclear
regions
Joanna Holt
13th October 2010, Kathmandu, Nepal
understanding AGN feedback is essential for understanding galaxy
evolution
radio galaxies are key objects, particularly in the early stages of evolution:
compact radio sources
extreme emission line OUTFLOWS (up to 2000 km s-1)
size appears to be important
kinematics/radio-optical alignment/density/temperature suggest outflows
might be driven by the expanding radio jets
outflows on small scales but we can not currently distinguish between AGN
winds and jets
Summary & conclusions
Joanna Holt
13th October 2010, Kathmandu, Nepal
new diagnostic provides crucial density measurements
energy in the warm gas outflow is at least an order of magnitude smaller
than what the majority of models require
is more energy locked into hotter/cooler gas phases?
are the powerful outflows at even earlier stages?
or are there problems with the simulations?
Summary & conclusions
compact radio sources are important probes of
AGN-induced feedback in the early stages of
AGN evolution
