Alberto Bolatto
GMC lifetime: 100 Myr (Scoville 79, Koda) Size-linewidth relation:
- Heyer 2001: small, flat dispersion clouds
- outer galaxy clouds contained by external pressure
Dust in IGM hints at molecular Galactic outflows
Jin Koda: Molecular to Total gas ratio
- inner 1 kpc 100% molecular
- 20-30% arm/interarm variations
- molecules within interam and in arms, but clumps only in arms + Sawada 2012 + Power-Law tails in arms, but not in interarms
- GRS more clumpy in arms
- arm/interarm comparison in M51 + 2-3x increase in T or rho in spiral arms
- Q Diederich: interarm clouds short-lived? Not self-gravitating?
- A: Molecular gas is surviving, small clumps are self-gravitating
- Why is BDI higher at tangent point?
- What about Bania's clump?
Superbubbles as a physical process in the ISM 15': Martin Krause
- Al26 is much faster than spiral arms
- Too fast orbital velocity...
- My question: What is the scale height? What directions is the Al26 going?
- expand 100 pc in all directions except back along the line of sight + Are the velocities consistent with the stellar velocity distribution?
Star Formation in molecular gas outside galaxies: Ute Lisenfeld
- Galaxies star forming, extragalactic gas with high column & high velocity dispersion not
- colliding galaxies: intergalactic region full of molecular gas
Andreas Schruba: CARMA + IRAM Andromeda survey
- All-galaxy survey with IRAM + 175 hr, 335 mosaic for "Brick 15"
- most clouds unbound or pressure bound
- size-linewidth relation: still lots of scatter
- sigma^2/r vs surface brightness (same as Heyer 2009 plot) + no correlation with any parameters...
- clouds in strongest star-forming regions have largest LOS velocity differences
Rahul Shetty: KS fitting
- Linear relation indicates constant depletion timescale
- super-linear: efficiency increases with increasing density
- linear: constant efficiency with gas density + GMCs all have similar/same properties + t_dep = 2 Gyr
- CO traces individual clouds
- sublinear indicates non-star-forming CO
- no universal or representative depletion time + depletion time increases with CO
- Adam Leroy: Surface density of H2 doesn't match surface density of molecular clouds
- Jin: Also found superlinear. Systematic bias?
Javier Cardiel: Two regimes of SF
- Looking for triggering
- density decreases with size increasing?
- HII regions and molecular clouds have same size-mass relations
Steve Longmore: ISM in Galactic Centers
dolphin riding? Where is MW in hubble tuning fork?
- dense gas with no star formation driven inwards by bar
- Meidt M51 PAWS
Molinari Ring: closed orbit... M83 is a twin Jay Gallagher's talk: SFR much, much higher in NGC 253 than MW Discrepancy between Farhad, Steve, and Sandstrom
- TOTAL gas: CMZ agrees
- Geometry: Farhad assumed pancake, Steve assumed ring
- Kruijssen & Longmore similarity to z=2-3...
- CMZ clouds "indistinguishable" in a few parameters from high-Z
- Turbulent pressure provides the support in the CMZ
- environmentally dependent density threshold
- Q Rowan: Constant gradient in cloud properties along the ring?
- Q Semadeni: Turbulence can't provide support.
- Q Keto: Nothing can supply the turbulence
- Q Falgarone: HCO+ absorption, daughter of CO+. Could trace sites of turbulence in the medium. Low density. Line width comes from intense shear.
Tim Davis: ISM in early-type galaxies
- ISM in CMZs different
- some are predominantely molecular (no HI)
- cluster members have different NII/CII ratios
- lower star forming efficiency
- shear increases depletion time
- Q Burkhart: Origin of gas. Replenishment from stars?
- A: Based on gas vs star kinematics, at least 50% must be accreted.
- Q Kruijssen: Stripping would happen if disk extends to optical radius. Does it? Stars should be stripped too
- A: Don't extend to optical radius, but more truncated in clusters
- Q Leroy: Where does tff claim come from...?
- A: assume all mol clds have 85 msun/pc^2...