IAU Commission 28 - GalaxiesHighlights 2005-08

Conferences

New OC

2

1- Star formation with

Spitzer and Galex

Star formation increases with z: Noeske et al 2007

2905 galaxiesAEGISGroth StripBlue: 24+ Emission linesGreen: no 24SF from EM, red

Gradual process of SF decline with time: gas exhaustion?

24 and H tracers of SFRMessier 51 Kennicutt et al 2007

Depends on the pixel average,Best on 520pc

M51

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2- Extended UV (XUV) disks

Gil de Paz et al 2007

Abundances in the outer parts are not pristine material, but like 1Gyr old disks

Type 1

UV NIR-opt

UVNIR-opt

Type 2

Thilker et al 2007

Frequent extended UVMight be episodicgas accretion

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3- Colour Bimodality and downsizing

30% of z~2 galaxies detected in 24 showexcess of mid-IR % star formation.

Stacked X-ray reveal Compton-thick AGNFraction increases with mass, and with z60% M> 1011Mo

Daddi et al 2007

Origin of bimodality?Cold gas accretion at low MQuenching of star formation M>Mo

Dekel & Birnboim 2006

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4- Evolution and High-z galaxies

Kristen et al 08, Genzel et al 08

Distinguishing between mergersand normal galaxies?

Tacconi et al 2006

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5- Scaling laws and time

evolution

Sheth et al 2008

Trachternach et al 2009

Baryonic Tully-FisherConstraint on triaxiality

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6- Numerical simulations

Via Lactea Diemand et al 2007

Di Matteo et al 2007, 08

Retrograde mergers producemore starburstsGlobally, only a few % of starburstdue to mergers

Satellite problem more accute

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Conferences

IAU S230: Populations of High Energy Sources in Galaxies, Aug 2005, Dublin, Ir11th Latin-American Regional IAU Meeting (LARIM-2005), Dec05, Pucon, ChileIAU S235 : Galaxy Evolution across the Hubble Time, Aug 2006, Prague, CzJD07: The Universe at z>6, Aug 2006, Prague, CzIAU S238: Black Holes -- from Stars to Galaxies, Aug 2006, Prague, CzIAU S241: Stellar Populations as Building Blocks of Galaxies, Dec 2006, Canaries, SpIAU S244: Dark Galaxies and Lost Baryons, June 2007, Cardiff, UKIAU S245: Formation and Evolution of Galaxy Bulges, July 2007, Oxford, UKIAU S254: The Galaxy Disk in Cosmological Context, June 2008 Copenhagen, Dk IAU S255 : Low-Metallicity Star Formation, June 2008, Rapallo, Liguria, ItIAU S256 The Magellanic System: Stars, Gas, and Galaxies, July 2008, Keele, UK

+ 100 other meetings relevant to Galaxies (cited in the report, 2005-08)10 times more than IAU!

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Commission actionsNew Organising Committee for 2009-2012

President Roger Davies (UK)Vice President Jay Gallagher (USA)

New OC membersStephane Courteau (Canada)Chanda Jog (India)Sharda Jogee (USA)Linda Tacconi (Germany)Elena Terlevich (Mex)

Continuing OC membersFrancoise Combes (F, past-president)Avishai Dekel (Israel)Marijn Franx (NL)Naomasa Nakai (Japan)Monica Rubio (Chile)

Main actions:Review meeting proposals

Proposition of Working GroupsLarge surveys?

IAU GA 2012