imaging star-forming gas in nearby galaxies with alma

Infrared Diagnostics of Galaxy EvolutionInfrared Diagnostics of Galaxy Evolution

Imaging star-forming gas in nearby galaxies

with ALMA

Imaging star-forming gas in nearby galaxies

with ALMA

Jean Turner (UCLA)Jean Turner (UCLA)

Imaging Star Formation in the Cosmos with ALMA

Imaging Star Formation in the Cosmos with ALMA Imaging Star Formation in the Cosmos with ALMA AAS Calgary 5 June 2006

ALMA studies of star formation on galactic scales complement Galactic and high z studies






Observed: Stellar populations, Hubble sequence, “beads on a string”, & Toomre Q







What is the relation of spiral structure to star formation?









Observed: LIR/MH2 well-correlated, Schmidt law, excellent correlation of HCN and LIR (Gao & Solomon 2005):



Observed: LIR/MH2 well-correlated, Schmidt law, excellent correlation of HCN and LIR (Gao & Solomon 2005):







Observed: LIR/MH2 well-correlated, Schmidt law, excellent correlation of HCN and LIR (Gao & Solomon 2005)

How do properties of the gas — atomic vs molecular, dense vs diffuse gas — determine star formation?



Observed: LIR/MH2 well-correlated, Schmidt law, excellent correlation of HCN and LIR (Gao & Solomon 2005)

How do properties of the gas — atomic vs molecular, dense vs diffuse gas — determine star formation?



ALMA resolution: 10 mas

<1 pc at Virgo

resolve individual SF regions, structure around AGN in the local universe

50 pc out to 900+ Mpc

GMCs, spiral features, galactic structure for a large sample of neaby galaxies

ALMA resolution: 10 mas

<1 pc at Virgo

resolve individual SF regions, structure around AGN in the local universe

50 pc out to 900+ Mpc

GMCs, spiral features, galactic structure for a large sample of neaby galaxies



Direct imaging of extragalactic star-forming regions: ALMA continuum

Direct imaging of extragalactic star-forming regions: ALMA continuum

Massive HII regions via their free-free emission

Super star clusters: imaging to 50 MpcOrions: image to ~10Mpc, detect to Virgo

Dust emission from low and high mass stars More sensitive than free-free

Local Group, 10 mas = .04 pc = 10,000 AU

Massive HII regions via their free-free emission

Super star clusters: imaging to 50 MpcOrions: image to ~10Mpc, detect to Virgo

Dust emission from low and high mass stars More sensitive than free-free

Local Group, 10 mas = .04 pc = 10,000 AU

Continuum sensitivities ~10 Jy in an hour



Direct imaging of molecular gas: ALMA line emission

Direct imaging of molecular gas: ALMA line emission

Imaging of molecular clouds in CO and other molecules

Imaging of molecular clouds in CO and other molecules

Line brightnesses ~ 0.01K in 10 hours



Care and feeding of AGNCare and feeding of AGN

NGC 1068 Seyfert 2 CO(1-0) CO(2-1)

Plateau de Bure Interf. Schinnerer et al. 2000



Nurturing of star formation in galaxies


N. Sharp, NOAO



N. Sharp, NOAO Helfer et al. 2003

CO BIMA-SONG





F. Calvert, A. Block, NOAO/AURA/NSF Helfer et al. 2003

CO BIMA-SONG





ALMA is designed to detect extended structure


M83





M83

AAT D. Malin

CO (green): NRAO 12 meter telescope HI (red): VLA (NRAO/AUI/NSF)

Crosthwaite et al. 2003



ALMA can study gas and interactions

ALMA can study gas and interactions

VLA NRAO/AUI/NSF Yun, Ho, Lo 1994



The world of moleculesThe world of molecules



Detecting molecular gasDetecting molecular gas




H2 is “silent” unless it is hot (100 K)





CO is a pretty good tracer, easily excited (5.5 K, low densities), abundant, bright.





CO is a pretty good tracer, easily excited (5.5 K, low densities), abundant, bright.

How good is “pretty good”? To factor of two within Galaxy (gamma rays);Overpredicts gas mass in metal-rich galactic

centers.Situation in low metallicity galaxies unclearFreeze-out in densest clouds



Detected interstellar moleculesDetected interstellar molecules

H2 HD H3+ H2D+ CH CH+ C2 CH2 C2H *C3

CH3 C2H2 C3H(lin) c-C3H *CH4 C4

c-C3H2 H2CCC(lin) C4H *C5 *C2H4 C5HH2C4(lin) *HC4H CH3C2H C6H *HC6H H2C6

*C7H CH3C4H C8H *C6H6

OH CO CO+ H2O HCO HCO+HOC+ C2O CO2 H3O+ HOCO+ H2COC3O CH2CO HCOOH H2COH+ CH3OH CH2CHOCH2CHOH CH2CHCHO HC2CHO C5O CH3CHO c-C2H4O CH3OCHO CH2OHCHO CH3COOH CH3OCH3 CH3CH2OH CH3CH2CHO(CH3)2CO HOCH2CH2OH C2H5OCH3 (CH2OH)2CONH CN N2 NH2 HCN HNC N2H+ NH3 HCNH+ H2CN HCCN C3NCH2CN CH2NH HC2CN HC2NC NH2CN C3NHCH3CN CH3NC HC3NH+ *HC4N C5N CH3NH2

CH2CHCN HC5N CH3C3N CH3CH2CN HC7N CH3C5N? HC9N HC11NNO HNO N2O HNCO NH2CHO SH CS SO SO+ NS SiH*SiC SiN SiO SiS HCl *NaCl*AlCl *KCl HF *AlF *CP PNH2S C2S SO2 OCS HCS+ c-SiC2

*SiCN *SiNC *NaCN *MgCN *MgNC *AlNCH2CS HNCS C3S c-SiC3 *SiH4 *SiC4

CH3SH C5S FeO

DEMIRM



Chemistry in GalaxiesChemistry in Galaxies

Pioneering single dish work on the IRAM 30m

Henkel, Mauersberger et al., resolutions ~ 30” (300-500 pc in even the closest galaxies)

Galaxies can have distinctive chemistries

Pioneering single dish work on the IRAM 30m

Henkel, Mauersberger et al., resolutions ~ 30” (300-500 pc in even the closest galaxies)

Galaxies can have distinctive chemistries



Imaging Chemistry in GalaxiesImaging Chemistry in Galaxies

IC 342 — Owens Valley Millimeter ArrayIC 342 — Owens Valley Millimeter Array

N2H+ HNC HC3N C2H C34S HNCO CH3OH

Meier & Turner 2005




IC 342 — Owens Valley Millimeter Array


PC Axis 1:

Density-weightedmean column density

Gas density: CO, N2H+, HCN

Meier & Turner 2005






PC Axis 1:

Density-weightedmean column density

PC Axis 2:

Shock tracers vs PDR molecules

Gas density: CO, N2H+, HCNC2H: PDR

Methanol, HCNO: shocks

Meier & Turner 2005





M82 — BIMA Array

Not detected in M82 maps: shock tracers SiO, HNCO, CH3OH


M82 — BIMA Array

Not detected in M82 maps: shock tracers SiO, HNCO, CH3OH

– X X

Meier & Turner 2005, 2006



ALMA: Imaging star-forming gas in nearby galaxies

summary

ALMA will be a powerful imaging device

HII regions (free-free)dust emission (low and high mass SF)

molecular clouds on sizescales of 1pc (SF regions, AGN)to galaxy-wide, out to hundreds of Mpc

IT WILL BE GREAT!

ALMA: Imaging star-forming gas in nearby galaxies

summary

ALMA will be a powerful imaging device

HII regions (free-free)dust emission (low and high mass SF)

molecular clouds on sizescales of 1pc (SF regions, AGN)to galaxy-wide, out to hundreds of Mpc

IT WILL BE GREAT!



ALMA

LMC

imaging star-forming gas in nearby galaxies with alma

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