1. HST HII regions & optical light Eva Schinnerer Max Planck Institute for Astronomy molecular gas (PAWS) 1 kpc Star Formation and ISM in Nearby Galaxies: The PAWS View

2. 3 Paradigms on Giant Molecular Clouds 1.most of the molecular gas resides in GMCs 2.GMC properties are universal across environments/galaxies 3.massive star formation and GMCs are closely associated

3. 9 kpc release of public data products: early 2012 IRAM Large Program 30m: 40 hr PdBI: 170 hr M51

4. PdBI Arcsecond Whirlpool Survey Eva Schinnerer (PI)MPIA Annie HughesMPIA Dario ColomboMPIAPoster #14 Sharon MeidtMPIA Adam LeroyNRAO Jerome PetyIRAM Gaelle DumasIRAM Karl SchusterIRAM Clare DobbsMPE Todd ThompsonOSU Santiago Garcia- Burillo OAN Carsten KramerIRAM Hans-Walter RixMPIA

5. PAWS – PdBI Arcsecond Whirlpool Survey largest PdBI mosaic done 60 pointings split in 2 sets FoV ~ 43” per pointing sensitivity reached:5  ~1 GMC 1.2x10 5 M sun at 40 pc (1.1’’) resolution CO(2-1) HERA Schuster et al. (2007)

6. Molecular Gas Disk of M51 Schuster et al. (2007) single dish (~ 500 pc)

7. Molecular Gas Disk of M51 Schinnerer et al. (in prep.) mm-interferometer (~ 40pc)

8. Molecular Gas disk of M51 Colombo et al. (in prep.) Velocity field

9. Molecular Gas disk of M51 Colombo et al. (in prep.) environmental mask nuclear bar in center inter-arm spiral arm

10. Stellar Potential  Spiral Arms are not the Same 3.6  m corrected Meidt et al. (in prep.)

11. 3 Paradigms on Giant Molecular Clouds 1.most of the molecular gas resides in GMCs 2.GMC properties are universal across environments/galaxies 3.massive star formation and GMCs are closely associated

12. Resolved Emission in Molecular Gas Disk combined resolved extended 100% 33% 66% combined – resolved (PdBI-only) = extended intensity velocity Pety et al. (in prep.)

13. GMC Fraction in Molecular Gas Disk CO(1-0) intensity linear stretch

14. GMC Fraction in Molecular Gas Disk Colombo et al. (in prep.) GMCs only preliminary(!)

15. GMC Fraction in Molecular Gas Disk Colombo et al. (in prep.) Preliminary analysis: ~ 900 GMCs identified ~ 50% have M(H 2 ) > 10 6 M sun ~ 30% of total CO flux center: 13% inter-arm: 40% spiral arms: 47%

16. Diffuse Component in Molecular Gas Disk 12 CO/ 13 CO = 6, 8, 11 M51 @ 23’’ Pety et al. (in prep.) 12 CO/ 13 CO consistent w/ mixture of diffuse & dense material (e.g. Polk et al. 1988)

17. 3 Paradigms on Giant Molecular Clouds 1.most of the molecular gas resides in GMCs  Not at all, but further testing required 2.GMC properties are universal across environments/galaxies 3.massive star formation and GMCs are closely associated

18. GMC Properties I. Biases Colombo et al. (in prep.) log r [pc] Log  v [km/s] We used: same GMC extraction algorithm & parameters (CPROPS) (following Bolatto et al. 2008) CO data cubes at native resolution  resolution bias on GMC properties  deblending issue in crowded regions (?) resolution limits Poster #14  Dario Colombo

19. ‘GMC’ Properties II. Nearby Galaxies Hughes et al. (in prep.) same extraction parameters (CPROPS) for ‘islands’ data cubes at same resolution   CO not the same log r [pc] log L CO [K km/s/pc 2 ] 1 M sun /pc 2 10100 log M lum [M sun ] log N cl [(m>M)/kpc 2 ] If average disk scale height same  Different mass spectra

20. log r [pc] ‘GMC’ Properties III. Galactic Environment Colombo et al. (in prep.) Same extraction parameters (CPROPS) on single data set   CO the same irrespective of galactic environment  Mass spectrum highly dependent on environment (crowding?) log L CO [K km/s/pc 2 ] 1 M sun /pc 2 10100 log M lum [M sun ] log N cl [(m>M)/kpc 2 ] M51

21. SFR surface density (M sun /yr/kpc 2 ) 30 disk galaxies @ 1 kpc Bigiel et al. (2011) depletion time t= H 2 surface density (M sun /pc 2 ) M51 LMC GMC Properties in Different Environments

22. 3 Paradigms on Giant Molecular Clouds 1.most of the molecular gas resides in GMCs  Not at all, but further testing required 2.GMC properties are universal across environments/galaxies  No, arm/inter-arm, low/high  gas 3.massive star formation and GMCs are closely associated

23. Relation of Gas and Star Formation aperture size I(CO) > 3  inter-arm center CO non-detection …. OLS fit @ 1kpc Larger apertures: scatter decreases slope steepens SFRI(CO)HI+H 2 1.4 GHz0.80.9 24  m 0.91.3 HH 1.10.9 8  m 0.91.0 Hughes et al. (in prep.) log I CO [K km/s] log  H  [erg/s/cm 2 /sr]

24. 20cm HST i-H 24  m HST H  Spatial Relation of Gas and Star Formation Schinnerer et al. (in prep.)

25. Spatial Relation of Gas and Star Formation ISM: CO & I-H potential well: H band star formation: B band

26. CO, IR, CO+IR Spatial Relation of Gas and Star Formation CO, Ha, CO+Ha 1.9” 6.0” 12” CO, RC, CO+RC 80 pc 250 pc 500 pc

27. Relation of Gas and Giant HII regions 90 pc apertures centered on grouped HII regions: effects of age and environment? 1:1 correspondence log  H  [erg/s/pc 2 ] Log  H2 [M sun /pc 2 ]

28. Dobbs & Pringle (2010) GMC & SF Formation in Spiral Wave Model when and where does SF start?  Dobbs (2008)  gas spurs/feathers should develop

29. Northern spiral arm molecular gas in arms and spurs/feathers (as expected from models)

30. Northern spiral arm molecular gas in arms and spurs/feathers HII regions w/i spurs/feathers, no H  in gas arm (Vogel ea 1988)

31. Northern spiral arm molecular gas in arms and spurs/feathers HII regions w/i spurs/feathers, no H  in gas arm no hot dust emission in gas arm  delay between GMC and star formation?

32. 3 Paradigms on Giant Molecular Clouds 1.most of the molecular gas resides in GMCs  Not at all, but further testing required 2.GMC properties are universal across environments/galaxies  No, arm/inter-arm, low/high  gas 3.massive star formation and GMCs are closely associated  Not always, depends on environment

34. GMC Properties in Different Environments PropertyM51LMCNotes ΣH 2 [M pc -2 ]851global ΣHI [M pc -2 ]830global Z/Zo30.5global Σ* [M/pc -2 ]~300~50global ΣH 2 [M pc -2 ]23030cloud T max [K]42cloud σ v [km s -1 ]72cloud R [pc]8020cloud Two ISM ‘extremes’: LMC properties from Hughes et al. (2010)

35. The conversion factor in M51a’s spiral arms 13 CO(1-0) 12 CO(1-0) 12 CO(2-1) Ideally add more lines: higher transitions or isotopes, but …

36. 13 CO(1-0) 12 CO(1-0) Ideally add more lines: higher transitions or isotopes, but … LVG Large Velocity Gradient (LVG analysis)  values for T kin, n(H 2 ) very similar to MW