Star Formation and Dynamics in Galaxies

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Star Formation and Dynamics in Galaxies

Santiago GARCIA-BURILLO Observatorio Astronómico
Nacional (OAN)-Spain
The Dusty Universe, October 27-29, 2004, Paris,
France
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OUTLINE
CO lines

• Dynamics of galaxy disks -Resolving individual
  molecular clouds -Testing density wave theories
  spiral waves and bars -Probing the disk-halo
  interface molecular outflows

• Dynamics of galaxy nuclei -AGN feeding
  -SB-AGN connection

Beyond CO...

• Molecular gas chemistry in galaxies (SB,
  AGN) -Shock chemistry in SB -PDR chemistry in
  SB -XDR chemistry in AGN

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Dynamics of Disks (I) Resolving Molecular Clouds

The case of M31 Neininger et al 1998 Guelin et
al 2000, 2004 Muller 2003
CO(1-0) 30m map of M31
-gt M31 closest spiral galaxy (14pc) with
well-known distance.-gt 30m PdBure
Interferometer CO(1-0) and CO(2-1)
maps-gtInterferometer maps resolve individual
molecular clouds--gt determination of molecular
cloud properties sizes, vel.disp, temperatures
and clouds masses....
Addressing cloud mass determination from virial
theorem--gtstandard it does not
work!--gtbalistic it works with X1-2!--gtLOWER
CO--to--H2 conversion factor (also) for disks,
not only for nuclei!
Bure minmaps
30m map
ALMA will resolve individual molecular clouds
out to D50Mpc
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Dynamics of Disks (II) Spiral Waves
The case of M51 Schinnerer et al 2004
12CO(1-0) OVRO30m
-gt M51 grand design spiral galaxy (145pc)-gt
OVRO (Aalto et al. 1999) 30m (Garcia-Burillo et
al. 1993) 12CO(1-0), 12CO(2-1),
13CO(1-0)C18O(1-0)-gtInterferometer maps identify
GMA--gt determination of molecular gas properties
on spiral arms and interarm regions as a function
of radius.
A challenging case study for density wave
theory--gtDynamics strong streaming motions
50-100km/s on 100pc scales --gtSF trigger
Halpha a long way downstream
ALMA will resolve molecular spiral arms in
galaxies out to D500Mpc
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Dynamics of Disks (III) Bars
Bars as engines of galactic evolution
Pattern speed evolution in bars, from
Bournaud and Combes 2002
--gtSimulations suggest bar instabilities
experience significant secular evolution
depending on gas accretion(Bournaud and Combes
2002 Englmaier and Sloshman 2004).
Ma
Ma
--gt CO mapping of bars in galaxy disks on several
scales provide constraints to- bar pattern
speeds - feasibility of decoupling of bars fully
tested by observations. --gtBar properties as a
function of z?(Jogee et al 2004)
ALMA will allow studies of molecular bars in
galaxies out to D500-1000Mpc
Decoupled bars in M100, from García-Burillo et al
1998
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Molecular gas drawn out of galaxy disks
starbursts
Dynamics of Disks (IV) The Disk-Halo Interface

M82 a huge molecular gas halo! (Seaquist and
Clark 2001, García-Burillo et al 2001, Walter et
al 2002)
PdBI SiO(2-1) map García-Burillo et al 2001

• IRAM PdBI one-field map shows SiO emission
  extends out of galaxy plane! chimneysupershell.

SiO chimney
OVRO CO(1-0) map Walter et al 2002
The tip of the iceberg!
SiO supershell

• ALMA will make possible high-resolution mapping
  of extreme starbursts as M82 key to understand
  high-z galaxies !

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OUTLINE
CO lines

• Dynamics of galaxy disks -Resolving individual
  molecular clouds -Testing density wave theories
  spiral waves and bars -Probing the disk-halo
  interface molecular outflows

• Dynamics of galaxy nuclei -AGN feeding
  -SB-AGN connection

Beyond CO...

• Molecular gas chemistry in galaxies (SB,
  AGN) -Shock chemistry in SB -PDR chemistry in
  SB -XDR chemistry in AGN

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Dynamics of Nuclei Feeding AGN (I)
What sets on activity in galaxies at present
...?
-gtAGN fuelled with material originally away from
gravitational field of BH problem of angular
momentum removal. -gt Critical scale for AGN
feeding lt100pc. AGN duty cycle is short! -gt
Search for correlation with secondary
instabilities from 500pc to 50 pc nuclear
bars? spiral gas waves?, nuclear-warps? m1
modes? ... No consensus on the driving
mechanism!...(only one? several?...)
( Combes 2000-2004 Wada et al 2000-2004
Englmaier Shlosman 2000 Shlosman 2001
Maciejewski et al 2002, 2004 Knapen 2001, 2004
Jogee 2004 Laine et al 2002 Garcia-Burillo et
al 2000, Schinnerer et al 2000.......and many
others!)
--gt High spatial resolution (0.5-1) CO
observations paramount to reach critical
scales lt50-100pc
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Dynamics of Nuclei Feeding AGN (II)
NUGA a CO survey of low-L AGN with IRAM PdbI
García-Burillo, Combes, Eckart et al 2003, 2004
LINER
T/LINER
HII/T
LINER/SEYF. 1
SEYF. 1
SEYF. 2
T/LINER
SEYF. 2
SEYF. 2
LINER
SEYF. 2
T/SEYF. 2
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Dynamics of Nuclei Feeding AGN (III)
García-Burillo, Combes, Schinnerer et al 2004
NGC4826
TRANSITION object
CO(2-1) on B-I/HST
Observational evidence of feeding?....
108Msun at rlt200 pc from AGN -kinematics
suggests outflow, not inflow! -m1
instability inhibits feeding at present? --gt
no evidence of ongoing feeding
NGC6951
Seyfert 2
CO(2-1) on J-H/HST
4x108 Msun trapped in starburst ring107Msun
at rlt200 pc from AGN -1/Central torus
106Msun (torus) --gt feeding in the
past -2/Bridge of 107Msun linked to
filamentary spiral seen in J-H HST map
--gt (low level) ongoing feeding
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Dynamics of Nuclei Feeding AGN (IV)
Garcia-Burillo, Combes, Schinnerer et al 2004
Gravity Torque Maps
Efficiency of Torques
-gtHST NIR images (0.2) allow derivation of
stellar gravity torques on molecular gas disk
from CO maps (0.5).
NGC4826
TRANSITION object
--gtgravity torques give angular momentum to gas
at rlt600pc --gt no ongoing feeding
(agreementwith CO diagnostic)
Seyfert 2
NGC6951
--gtgravity torques remove angular momentum from
gas down to r400pc --gtgravity torques have no
role at rlt200pc! --gt ongoing feeding maintained
by transitory mechanism?
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Dynamics of Nuclei Feeding AGN (IV)
Wide range of instabilities at r10-500 pc from
AGN m2, 1 - like and stochastic
perturbations. ---gt Not all instabilities feed
AGN, some do feed nuclear starbursts. ---gt Some
instabilities may inhibit AGN feeding.
High-resolution (0.5) CO maps of AGN allow
analysis of stellar gravity torques on gas.---gt
AGN feeding in Seyferts in two steps 1/
First, stellar torques feed nuclear SB on scales
of a few 100pc.
2/ A transitory mechanism involving little gas
feeds directly AGN

• ALMA will make high-resolution and
  high-sensitivity maps of a significant number of
  AGN hosts , zooming on the inner 10pc playground.

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OUTLINE
CO lines

• Dynamics of galaxy disks -Resolving individual
  molecular clouds -Testing density wave theories
  spiral waves and bars -Probing the disk-halo
  interface molecular outflows

• Dynamics of galaxy nuclei -AGN feeding
  -SB-AGN connection

Beyond CO...

• Molecular gas chemistry in galaxies (SB,
  AGN) -Shock chemistry in SB -PDR chemistry in
  SB -XDR chemistry in AGN

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Evolutionary trends in SB can be tracked down by
observation of different chemical tracers
Extragalactic Chemistry (I)
Energetic Processes in SB AGN (intense UV/X
Radiation, Shocks,Cosmic Rays...)
PHASES
PROCESSES
I/ ONSET OF THE NUCLEAR STARBURST gas infall
driven by density waves and/or tidal forces.

• Gas compression, HI ?H2, cloud-cloud collisions
  driving large-scale SHOCKS.

• UV field from massive stars create HII regions
  and PDR locally in disk.
• SHOCKS in YSO in disk
• XDR when AGN in disk.

II/ MASSIVE STAR FORMATION BURSTS Young
Stellar Objects and first SN explosions

• Strong UV fields create giant PDR in disk
• Expansion of gas heated by SN entrains neutral
  gas into halo driving SHOCKS
• PDR / SHOCKS in halo?

III/ BIPOLAR GIANT OUTFLOW gas plane breaks
out due to blast waves of SN remnants.
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Extragalactic Chemistry(II) Expanding the
Frequency Range
-gtPioneering work of R. MauersbergerC. Henkel
(80-90s) done with 30m telescope (12-27
resolution) in some galaxies for a limited
number of molecular species.
2mm Survey (40GHz broad) of the NGC253 with IRAM
30m (Martín et al. 2003, 2004)
LINE SURVEYS
NGC253
M82 and NGC253 spectra (4GHz broad) by S. Martín
(private communication)

• Different molecules provide
• diagnostic tools to explore starburst evolution
  M82 and NGC253 show different chemistries

M82
NGC253
Herschel (HIFI) will make multilines
/multispecies studies in the submm/IR for nearby
SB
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Extragalactic Chemistry(III) Using
Interferometers
OVRO maps of IC342 (Meier and Turner 2004)
High spatial resolution is paramount to probe
chemical differentation in galaxies!
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Extragalactic Chemistry(IV) Large-Scale Shocks
High spatial resolution needed to trace
evolution in starbursts

• SiO traces shocks in the disk of NGC253 (SF,
  density waves...) less evolved starburst.

• SiO traces shocks in the disk-halo interface in
  M82 giant outflow, evolved starburst.

SiO IRAM PdBI map in NGC253 from García-Burillo
et al 2000.
SiO IRAM-PdBI map (contours) from García-Burillo
et al. 2001 on CO (2-1) map from Weiss et al 2001
(colour ) in M82.
NGC253
M82
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Extragalactic Chemistry(V) PDR Chemistry
--gtM82 disk is a giant PDR of 600 pc size! (Mao
et al 2000, García-Burillo et al 2002 Fuente et
al 2004)
HCO PdBI map (García-Burillo et al 2002)
NeII contours(Achtermann Lacy 1995) on HCO map
---gtWidespread HCO emission detected in PdBI map
of the nucleus of M82 (García-Burillo et al
2002) ---gtGlobal HCO abundances comparable to
PDR X(HCO)4x10-10(Hollis Churchwell, 1983
Snyder et al 1985 Schilke et al 2001)
---gtInterferometer map shows strong variations
of X(HCO) within disk PDR Chemistry
propagates. ---gtDetection of HOC, emission of
small hydrocarbons and large CN/HCN ratios
corroborate PDR chemistry scenario (Fuente et al
2004)
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Extragalactic Chemistry(VI) XDR Chemistry
--gtX-rays suspected to heavily influence
molecular gas chemistry in the nuclear disks of
AGN (Tacconi et al 1994, Maloney et al 1996,
Kohno et al 2002, Usero et al 2004)
NGC1068
CO(1-0) (PdBISchinnerer et al. 00)
--gtX-ray driven chemistry models explain
abundance ratios measured in the CND of NGC1068
(Usero et al 2004)
Molecular Gas Inventory of the CND of NGC1068
--gtInfluence of X-rays on ULIRGs and embedded AGN
at high z to be explored with ALMA
Usero et al. 2004, AA, 419