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Star Formation and Dynamics in Galaxies

Star Formation and Dynamics in Galaxies. Santiago GARCIA-BURILLO Observatorio Astronómico Nacional (OAN)-Spain. The Dusty Universe, October 27-29, 2004, Paris, France. OUTLINE. CO lines.

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Star Formation and Dynamics in Galaxies

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  1. Star Formation and Dynamics in Galaxies Santiago GARCIA-BURILLO Observatorio Astronómico Nacional (OAN)-Spain The Dusty Universe, October 27-29, 2004, Paris, France

  2. 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

  3. 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 -> M31: closest spiral galaxy (1’’=4pc) with well-known distance.->30m + PdBure Interferometer CO(1-0) and CO(2-1) maps->Interferometer maps resolve individual molecular clouds--> determination of molecular cloud properties: sizes, vel.disp, temperatures and clouds masses.... Addressing cloud mass determination from virial theorem:-->standard: it does not work!-->balistic: it works with X=1-2!-->LOWER CO--to--H2 conversionfactor (also) for disks, not only for nuclei! Bure ‘minmaps’ 30m map ALMA will resolve individual molecular clouds out to D=50Mpc

  4. Dynamics of Disks (II): Spiral Waves 12CO(1-0) Aalto et al. (1999) The case of M51: Schinnerer et al 2004 12CO(1-0) OVRO+30m -> M51: grand design spiral galaxy (1’’=45pc)->OVRO (Aalto et al. 1999) +30m (Garcia-Burillo et al. 1993) : 12CO(1-0), 12CO(2-1), 13CO(1-0)C18O(1-0)->Interferometer maps identify GMA--> determination of molecular gas properties on spiral arms and interarm regions as a function of radius. A challenging case study for density wave theory:-->Dynamics: strong streaming motions: ~50-100km/s on 100pc scales -->SF trigger: Halpha ‘a long way’ downstream ALMA will resolve molecular spiral arms in galaxies out to D=500Mpc

  5. Dynamics of Disks (III): Bars Bars as engines of galactic evolution Pattern speed ‘evolution´ in bars, from Bournaud and Combes 2002 -->Simulations suggest bar instabilities experience significant secular evolution depending on gas accretion(Bournaud and Combes 2002; Englmaier and Sloshman 2004). Ma Ma -->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. -->Bar properties as a function of z?(Jogee et al 2004) ALMA will allow studies of molecular bars in galaxies out to D=500-1000Mpc Decoupled bars in M100, from García-Burillo et al 1998

  6. Dynamics of Disks (IV): The Disk-Halo Interface Molecular gas drawn out of galaxy disks: starbursts 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!:chimney+supershell. SiOchimney OVRO CO(1-0) map :Walter et al 2002 The tip of the iceberg! SiOsupershell • ALMA will make possible high-resolution mapping of extreme starbursts as M82: key to understand high-z galaxies !

  7. 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

  8. Dynamics of Nuclei : Feeding AGN (I) What sets on activity in galaxies ‘at present’ ...? ->AGN fuelled with material originally away from gravitational field of BH: problem of angular momentum removal. -> Critical scale for AGN feeding: <100pc. AGN duty cycle is short! -> Search for correlation with `secondary instabilities’ from 500pc to 50 pc: nuclear bars? spiral gas waves?, nuclear-warps? m=1 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!) -->High spatial resolution(0.5’’-1”) CO observations paramount to reach ‘critical’ scales: <50-100pc

  9. 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

  10. 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 r<200 pc from AGN: -kinematics suggests outflow, not inflow!-m=1 instability inhibits feeding at present?--> no evidence of ongoing feeding NGC6951 Seyfert 2 CO(2-1) on J-H/HST ~4x108 Msun ‘trapped’ in starburst ring~107Msun at r<200 pc from AGN: -1/Central ‘torus’ ~106Msun (torus)--> feeding in the past -2/Bridge of ~107Msun linked to filamentary spiral seen in J-H HST map--> (low level) ongoing feeding

  11. Dynamics of Nuclei : Feeding AGN (IV) Garcia-Burillo, Combes, Schinnerer et al 2004 Gravity Torque Maps Efficiency of Torques ->HST NIR images (0.2’’) allow derivation of stellar gravity torques on molecular gas disk from CO maps (0.5’’). NGC4826 TRANSITION object -->gravity torques give angular momentum to gas at r<600pc--> no ongoing feeding (agreementwith CO diagnostic) Seyfert 2 NGC6951 -->gravity torques remove angular momentum from gas down to r=400pc-->gravity torques have no role at r<200pc!--> ongoing feeding maintained by transitory mechanism?

  12. Dynamics of Nuclei : Feeding AGN (IV) Wide range of instabilities at r~10-500 pc from AGN: m=2, 1 - like and ‘stochastic’ perturbations.---> Not all instabilities feed AGN, some do feed nuclear starbursts. ---> Some instabilities may inhibit AGN feeding. High-resolution (0.5’’) CO maps of AGN allow analysis of stellar gravity torques on gas.---> 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.

  13. 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

  14. Extragalactic Chemistry (I) Evolutionary trends in SB can be tracked down by observation of different chemical tracers 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-scaleSHOCKS. • 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.

  15. Extragalactic Chemistry(II):Expanding the Frequency Range ->Pioneering work of R. Mauersberger+C. Henkel (80-90’s) 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

  16. Extragalactic Chemistry(III): Using Interferometers OVRO maps of IC342 (Meier and Turner 2004) High spatial resolution is paramount to probe chemical differentation in galaxies!

  17. 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 inM82:giant outflow, evolved starburst. SiO IRAM-PdBI map (contours) from García-Burillo et al. 2001 on CO (2-1) map from Weiss et al 2001 (colour ) in M82. SiO IRAM PdBI map in NGC253 from García-Burillo et al 2000. NGC253 M82 10´´

  18. Extragalactic Chemistry(V): PDR Chemistry -->M82 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 --->Widespread HCO emission detected in PdBI map of the nucleus of M82 (García-Burillo et al 2002) --->Global HCO abundances comparable to PDR: X(HCO)~4x10-10(Hollis & Churchwell, 1983; Snyder et al 1985; Schilke et al 2001) --->Interferometer map shows strong variations of X(HCO) within disk: PDR Chemistry propagates. --->Detection of HOC+, emission of small hydrocarbons and large CN/HCN ratios corroborate PDR chemistry scenario (Fuente et al 2004)

  19. Extragalactic Chemistry(VI): XDR Chemistry -->X-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) (PdBI;Schinnerer et al. 00) -->X-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 -->Influence of X-rays on ULIRGs and embedded AGN at high z to be explored with ALMA Usero et al. 2004, A&A, 419

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