Interstellar Medium and Star Formationin the Andromeda Galaxy

Andreas SchrubaCalifornia Institute of Technology

Adam Leroy, Karin Sandstrom, Fabian Walter,Alberto Bolatto, Nick Scoville, Julianne Dalcanton

Phases of the ISMHeidelberg, July 29 – Aug 1, 2013

Regulation of Star Formation in Molecular GasRingberg, June 24-28, 2013

CO Map from IRAM 30m

IRAM 30m:

85 pc x 2.5 km/srms ~ 30 mK

500pc

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CO Map from CARMA

CARMA:

175 hours335 p mosaic

20 pc x 1 km/srms ~ 250 mK

500pc

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Cloud Decomposition

CPROPStooRosolowsky & Leroy 2006;Leroy et al. (in prep)

• locate “islands” • break into “clouds”• get moments & flux

500pc

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Cloud Decomposition

500pc

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Cloud Decomposition

500pc

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Cloud Properties I

Aspect Ratio

Radius

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Lim

it

Velocity Dispersion

Lim

it

Peak Temperature

Lim

it

Cloud Properties IILuminous Mass

Lim

it

Virial Mass

Lim

it

Virial Parameter

Gra

vit

ati

onal Sta

bili

ty

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‘Larson’ Parameter

Lim

it

Linewidth – Size Relation

spirals

dwarfs

outer disk

Luminosity – Radius Relation

spirals

dwarfs

outer disk

Larson’s “Parameter”

spirals

dwarfs

outerdisk fix

ed e

xter

nal p

ress

ure

(Fie

ld e

t al.

2011

)

What controls nature of clouds (ie offsets)?… concordance of properties for neighboring clouds?

Concordance of Cloud Nature?500pc

avg cloud properties (σ2/l) for neighboring clouds

Concordance of Cloud Nature?Distance H2 Surface Density @ 200pc

SFR Surface Density @ 200pcCloud Mass

Cloud Motions

Concordance of Cloud Motions?Distance H2 Surface Density @ 200pc

SFR Surface Density @ 200pcCloud Mass

PHAT SF HistoriesGrad: Alexia Lewis

(U Washington)

Poster

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PHAT Cluster CatalogGrad: Lori Beerman

(U Washington)

PHAT Extinction MapExtinction AV = 1, 2, 3 mag

Julianne Dalcanton(U Washington)

PHAT Extinction Map

Extinction

Figure Credit:Cheoljong Lee (UVA)

Julianne Dalcanton(U Washington)

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PHAT Extinction Map

Dust Mass

Figure Credit:Cheoljong Lee (UVA)

Bruce Draine(Princeton)

PHAT Extinction Map

Atomic GasExtinctionMolecular Gas

Figure Credit:Cheoljong Lee (UVA)

Grad: Cheoljong Lee(U Virginia)

Regulation of Star Formation in Molecular GasRingberg, June 24-28, 2013

Final CARMA Survey

pointings: 1500area: 0.1 deg2 ~ 15 kpc2

beam: 20pc x 1 km/s clouds: 500-1000completion: end 2013