NEARBY GALAXIES AND ALMA

Transcription

1 NEARBY GALAXIES AND ALMA Jean Turner, UCLA

2 nearby galaxies close-up views of star formation & nuclear fueling on scales of GMCs and star clusters - where & how do galaxies form stars? - where does gas spend most of its time? - where does gas come from? - what is AGN fueling about? - what does feedback look like?

3 but early ALMA offers challenges for nearby, BIG galaxies

4 Herschel: fir dust emission in M51

5 ALMA Early Science vs full ALMA: imaging Messier objects are best done with full ALMA and ACA M51 Herschel PACS microns combined (ESA, PACS team, + JT Photoshop) 15 March 2011 Caltech ALMA Community Day, IPAC

6 M51 has been mapped in CO CARMA + NRO Koda et al. 2011

7 M51 CO pointings CARMA + NRO Koda et al. 2011

8 Messier objects best done with full ALMA, ACA model 12m only 12m + ACA Pety, Gueth, & Guilloteau 2001

9 dust continuum has the same problem as CO: very extended free-free continuum is OK: bright & compact but relatively weak. - detectable in 1 and 3mm bands - extinction-free tracer of star formation

10 ES bands & resolution good for nearby galaxies 5 Mpc: ~6-30 pc FOV : ~ pc 50 Mpc: ~ pc FOV: pc

11 high CO transitions are compact ALMA test image: CO(2-1) and CO(6-5) with 5 antennas E/k(J=7) ~110K

12 ALMA can spatially separate hot & cold gas rotational diagrams for CS indicate two temperatures K observed in ammonia even in quiescent galaxies (IC 342) Mauersberger et al m, Bayet et al. 2011

13 detected extragalactic molecules 2 Atoms 3 Atoms 4 Atoms 5 atoms 6 Atoms 7 Atoms H 2 (+1) H 2 O H 2 CO c-c 3 H 2 CH 3 OH CH 3 CCH OH HCN (+2) H 2 CS HC 3 N CH 3 CN CO (+3) HNC (+2) NH 3 CH 2 NH CH HCO HNCO NH 2 CN CS (+2) Italics = tenta,ve HCO + (+3) C 3 H CH + H 2 S HOCO + CO + SO 2 NO C 2 H CN HOC + NS C 2 S SiO N 2 H + (+1) SO (+1) OCS LiH H 3 + * NGC 253 s chemistry closely resembles that of Sgr B2(M) (B. Turner 1989) To Date: * 35 (+ 4 tenta[vely) detected species * 13 (+ 2 tenta[vely) detected rare isotopic subs[tu[ons (compiled: MarVn et al 2006; updated by Meier) 15 March 2011 Caltech ALMA Community Day, IPAC

14 3mm & 2mm surveys MarVn et al. 2006, 30m 15 March 2011 Snell et al. 2011, FCRAO 14m Caltech ALMA Community Day, IPAC

15 1mm spectrum, Arp 220 Martín et al.

16 imaging chemistry IC 342 central 300 pc λ=3mm N 2 H + HNC HC 3 N C 2 H C 34 S HNCO CH 3 OH CO is not the whole story! molecular abundances are sensitive tracers of galactic environment OVRO, Meier & Turner 2005

17 imaging chemistry IC 342 central 300 pc λ=3mm N 2 H + HNC HC 3 N C 2 H C 34 S HNCO CH 3 OH quiescent gas star formation tracer dense gas PDR molecule: high radiation fields grain chemistry; tracers of gentle shocks? OVRO, Meier & Turner 2005

18 imaging chemistry IC 342 central 300 pc λ=3mm N 2 H + HNC HC 3 N C 2 H C 34 S HNCO CH 3 OH quiescent gas star formation tracer dense gas PDR molecule: high radiation fields grain chemistry; tracers of gentle shocks? OVRO, Meier & Turner 2005 M82 is a giant PDR OVRO, BIMA Meier & Turner 2005, 2010 Garcia-Burillo +02, Mauersberger & Henkel 1991, Henkel et al. 1991

19 gas & star formation Gao & Solomon 2004 HCN is better correlated with L IR than is CO HCN vs L IR CO vs L IR

20 gas & star formation Gao & Solomon 2004 HCN is better correlated with L IR than is CO HCN vs L IR - is this because it is tracing dense gas? - or is it an excitation effect? IR pumping CO vs L IR

21 two dense gas tracers in IC342 HNC HC 3 N HCN follows free-free emission faithfully

22 how to fuel AGN NGC 6951 (Sy 2, 23 Mpc, 1 =110 pc) inner 4 kpc inner 30 of NGC 6951 gas response to largescale stellar bar causes gas inflow to 400 pc but not any closer in smaller stellar oval likely candidate for inflow in nuclear region IRAM PdBI, NUGA project van der Laan et al. 2011

23 15 March 2011 Caltech ALMA Community Day, IPAC

24 PDR vs XDR Meijerink & Spaans 2005 X-rays penetrate deeply and uniformly into clouds, enhancing chemical abundances of many species

25 what is feedback? Arp 220 two nuclei two counterrotating CO disks 1 ~ 360 pc OVRO: Sakamoto et al. 1999

26 what is feedback? Arp 220 HCO+(4-3) HCO+(3-2) CO(3-2) 870μ high res 870μ con[nuum compact, luminous western source 1 ~ 360 pc 0.3 ~100 pc Sakamoto et al SMA Sakamoto et al. 2009

27 what is feedback? Arp 220 ~100 km/s molecular oujlow, poten[ally 100 M /yr high res 870μ con[nuum compact, luminous western source HCO+(4-3) HCO+(3-2) CO(3-2) 870μ 1 ~ 360 pc 0.3 ~100 pc Sakamoto et al SMA Sakamoto et al. 2009

28 early ALMA & nearby galaxies early ALMA will be great for imaging of hot & dense gas extragalactic chemistry & radiative feedback from star formation AGN chemical diagnostics (PDRs, XDRs, shocks) kinematics of everything AGN fueling at the ~50 pc scale (NGC 4945, Circinus) full ALMA will give high resolution & sensitivity for pc-scale gas structures in starburst galaxies &AGN extended disks of normal spiral galaxies in dust &CO

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