Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
The interplay between The interplay between radio jets and ISM in sub-radio jets and ISM in sub-
kpc radio sourceskpc radio sourcesevolution of jets interacting with their evolution of jets interacting with their
environment as seen in small and environment as seen in small and intermediate scale objects intermediate scale objects
Raffaella MorgantiRaffaella MorgantiASTRON, DwingelooASTRON, Dwingeloo
Kapteyn Inst. GroningenKapteyn Inst. Groningen
Clive Tadhunter, Tom Oosterloo, Joanna Holt, Bjorn Emonts
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Characteristics and effects of jet-ISM interaction: why important?
• Effect of the ISM on the radio jet: doesn’t care? momentarily disrupt? frustrated? destroyed?
• Effects of the jets on the surrounding ISM: gas outflow clearing the circum-nuclear regions?
Interaction radio jets/ISM is one of the possible mechanisms for triggering outflows (together with radiation pressure and starburst winds)
important for the evolution of the host galaxy
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Following a hierarchical scenario:
evolution of AGN vs host galaxy
Start of merger-1 billion yr
Advanced merger: gas driventowards nucleus; starburst-0.5 billion yr
Quasar and jet activity drives gas out of galaxyNow
RelaxedE-galaxy+1 billion yr
from Clive Tadhunter
onset of radio activity related to accretion or merger -> but variety of conditions in the merger
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Initial phase of AGN can be crucial in the evolution of the host galaxy
in radio-loud objects we know which one are YOUNG AGN (e.g. CSS/GPS)
thus we can study their effect on the medium
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
We use the (kinematics of the) gas to We use the (kinematics of the) gas to trace what is happening in the trace what is happening in the
central regions of active galaxiescentral regions of active galaxies
• Atomic neutral hydrogen • Ionised gas• Molecular gas (talk Patrick Ogle)
complementary information
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Gas in (the centre of) early-type (field) galaxies:
important and very common component
In general (not only AGN selected early-type):
• Ionised gas -> ~70% detected, complex kinematics, kinematical decoupled cores etc. -> external origin of the gas in many cases (but not all!)
• Neutral hydrogen emission (on large scale) absorption (for radio-loud): can explore the small scales comparison compact/extended
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
HI in EMISSION: 70% detection rate for deep observations (down to few x 106 Msun)
HI in early-type galaxies200
k pcATCA data
HI total intensity + optical
Serra et al. 2005
(van Langevelde et al. 2000)
NGC 4261
HI in ABSORPTION: detected in ~30% of radio loud
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
How about sub-kpc (CSS/GPS) radio sources:
• is gas (ionised/neutral) present? and how compares to what found in large radio galaxies?
• are they (CSS/GPS) really moving through a dense medium?
• kinematics of the gas?
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
- Typical optical depth for radio galaxies: ~0.01 – 0.05
- High optical depth 0.1-0.2 detected in Seyferts and small/young sources.
- High detection rate of HI in CSS/GPS (e.g. Vermeulen et al. 2005) (not so clear for HFP Orienti et al. 2006)
)1( eScS cf −=Δ
upper limits
optical depth
Gallimore et al.
Vermeulen et al.
Morganti et al.
Typical HI column densities: 1019 - few times 1020 cm-2
for Tspin=100 K BUT Tspin can be up to few 1000 K
Atomic neutral hydrogen in large vs compact radio sources
Narrow (100-200 km/s) absorption component, associated with settled gas (e.g. circum-nuclear disks, halo, clouds e.g. see 4C12.50)
BUT NOT THE FULL STORY!
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
radio jet
The nuclear regionsprobed by the HI
extra-gas surrounding the AGN,e.g. left over from the merger that triggered the AGN
HI absorption from the torus or from circumnuclear disks
Cygnus A
Conway & Blanco 1995
~150 km/s
fast HI outflows
1400 km/s
WSRT Morganti et al. 2003
shocks
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
WSRT observations of broad HI absorption
Up to 2000 km/s width, optical depth <<1% Column density few times 1021 cm-2 (for Tspin = 1000 K)Mostly blueshifted HI outflows - Morganti, Oosterloo, Tadhunter A&A 2005
~0.003
~1500 km/s
~0.004 ~0.0023
~0.0005 ~0.006 ~0.002
~1400 km/s ~1000 km/s
~800 km/s ~2000 km/s~2000 km/s
~600 km/s
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
• Radio sources with detected fast HI outflows are either mainly compact/young or large with steep-spectrum cores (considered to be objects with restarted radio activity: 3C293 and 3C236)
All with rich ISM (CO, farIR....)
• Outflows detected in off-nuclear regions: jet-ISM interactionOutflows detected (with similar characteristics) both in ionised AND neutral gas!
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
The case of 3C305
WSRTVLA
core
500 km/s
VLAHI
•The broad HI absorption is found off-nucleus at the location of the radio lobe (about 1.6kpc
from the nucleus)•column density 2x1021 cm-2 (for Tspin=1000K)
•Mass outflowing gas ~106 Msun
Morganti, Oosterloo, Tadhunter, van Moorsel & Emonts 2005 A&A
1 kpc
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Jet-driven outflows can have an impact on the evolution of a galaxy comparable to starburst-driven superwinds
• Bulk kinetic energy: ~ few x 1057 erg (over a lifetime of a radio jet)
Rupke, Veilleux, Sanders 2002, 2005
Radio Galaxies
Mass outflow rate between a few and ~50 Msun/yr
comparable (lower end) to that found in Ultraluminous IR galaxies
Relevant impact in the evolution of the galaxy?
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Comparison between young (compact) and extended radio sources
• 14 powerful CSS/GPS from 3C/4C-2Jy samples
• 11/14 show evidence for fast outflows
– systemic to broadest component
– different distributions: K-S test significance: 99.9%
• size is important
Histograms: systemic-broadest
Num
ber
of s
ourc
esN
umbe
r of
sou
rces
Extended radio sources (Taylor 2004)
Compact radio sources (Holt 2005)
Shift (km s-1)
Shift (km s-1)
GPS
CSS
Other
Holt (2005)
PhD work of Joanna Holt
Ionised gas
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
General results on ionized and neutral General results on ionized and neutral hydrogen in compact sources hydrogen in compact sources
Indication of a rich medium around these objects?
• Broader & blueshifted optical emission lines are associated with compact radio sources: fast outflow of ionised gas very common
• Higher HI column density and fast HI outflows detected (produced by the interaction between the radio jet and the surrounding dense medium)
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Detailed study of two objects and the connection atomic neutral - ionised gas
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
-450 km/s
-2000 km/s
[OIII] ProfilesWHT+ISIS
Holt et al. 2002
HST [OIII] VLBI
Compact and powerful radio galaxy (P5GHz = 10
26 W Hz-1)
Far-IR bright, LIR~2x1012 Lsun
Large amount of CO, ~ 1010 Msun
Very rich ISM
4C12.50 and its unfriendly medium
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
AGN feedback: outflowsExtended [O II]3727 emission
Deep HI 21cm absorption (Mirabel 89,
Morganti et al 03)
[O III] emission in the
nucleus
broad
narrow
intermediateblueshift ~ 400 km s-1
blueshift ~ 2000 km s-
1
(Holt et al 03a,b)
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
AGN feedback: outflowsExtended [O II]3727 emission
Deep HI 21cm absorption (Mirabel 89,
Morganti et al 03)
[O III] emission in the
nucleus
(Morganti et al 03)
(Holt et al 03a,b)
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Observer’s L.O.S.
quiescent halo emitting narrow component
narrow component
broad component
intermediate component
obscured quasar
bi-polar radio jets
bi-polar radio jets
The broadest components are the most highly reddened & higher density (> 5000 cm-3)
Bow shock
Jet
HI clouds
[OIII] clouds
Shocked clouds
[OII]-emitting cocoon
Far side of galaxy, completely obscured from view
Stratified outflow
Upper limit for the total mass of line emitting gas (kinematically disturbed component combined) < 106 Msun
- too low for frustrating, confining the source
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
radio jethigh densitycloud
2D simulationsBicknell et al. 2003
4C12.50
Core
black=WSRTred = VLBI
Integrated HI profile
Mass of the HI cloud ~105-6 Msun
High column density (NH~10
22 cm-2)HI absorption
Global VLBI
Morganti, Oosterloo, Vermeulen et al. 2004
HI at the systemic tracing a clumpy medium
Case of 4C12.50: the jet is “fighting” its way out of a rich medium?
~50pc
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
PKS 1549-79: an example of a radio source in the early-
stage of its evolution• Recent major merger: tidal tails in optical, young
stellar population (50-250 Myr)• Core-jet radio structure: close
to the line-of-sight• HI absorption surprisingly present• No broad permitted (optical) lines
but Pa in NIR• Broad blueshifted (outflowing)
component e.g. [OIII]5007
VLT+FORS1: Gunn r (Batcheldor et al. 2007)
(King 1996)
2.3 GHz
Broad [OIII](FWHM~1350km/s)blueshift ~ 680 km s-1
Narrow H(FWHM<400km/s) HI
centre
NTT+EMMI & VLT+FORS2
VLBI
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
PKS 1549-79: in a stage where the nucleus is still hidden (in the optical) by the gas/dust coming from the merger that
triggered the radio sourceObserver’s
L.O.S.
[O II]-emitting
disk/cocoon• young, small scale radio jets
• expanding through dense cocoon
• sweep aside gas and dust
• AGN driven outflow will eventually remove the gas
PKS1549-79AAT/IRIS2K-band
FWHM = 1950 ± 40 km/s
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
core
Tzioumis et al.
1.2GHz
[OII]
[OII]
~200 pc
Not enough sensitivity to detect broad HI, but the HI at the systemic velocity represents the cocoon around the radio source
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
.mass outflow rate:
0.12 < M < 12 M๏ yr-1
mass of ionised gas in the outflow : 1.9x104 < M๏ < 1.9x106
. energy flux: 5.1x1040 < E < 5.1x1042 erg s-1
Main problem: relatively modest warm gas outflow
• the warm-gas outflow is not large! more in cold/hot gas?
• not as large as expected in the quasars feedback model
• it will not be able to clear all gas
• amount of ionised gas: not large to stop the jet
1.5x10-6 < E/Ledd < 1.5x10-4
Only small fraction of accretion power
.
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Results from the study of single objects
• Interaction important - many effects seen
• complex, stratified structure of the ionised gas outflow
• the gas masses do not seem to be large enough to frustrate the source
• but likely slowing down the evolution of the jets.
• mass outflow not enough as expected in feedback models ?
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
For nearby (z < 0.04) lower luminosity, compact sources the situation could be different (see also talk Giroletti)
not all GPS/CSS become large galaxies? but not necessarily because of the interaction? different evolution?
large amount of HI in emission around nearby CSS: connected to their origin?
BUT we don’t see large sources with such large HI disks.
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
• HI-rich compact radio sources do not grow into extended sources
(either because frustrated by the ISM in the central region of the galaxy or because the fuel stops before the source expands)
Remarkable trend: radio galaxies with large amounts (MHI >109 Msun) of extended (many tens of kpc up to 200 kpc!) HI disks all have a compact radio source
Emonts et al. 2006, astro-ph/0701438
Nearby (z<0.04) compact radio sources~1kpc ~1kpc
Giroletti et al. 2004Morganti et al. 2006
NGC 3894
Raffaella Morganti Extragalactic jets, Girdwood (May 2007)
Results
Powerful compact sources• Interaction important - many effects seen • complex, stratified structure of the ionised gas
outflow• the masse of the gas involved does not seem to be
large enough to frustrate the source• but likely slowing down the evolution of the
jets.
Nearby low-luminosity compact sources• different evolution? • some of them just fade away? do not grow to large
size
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