Magpop Midterm ReviewNode OAMP-LAM, Marseille

Coordinator: V. Buat

E.R.: Jakob Walcher

S. Arnouts1, S. Boissier, A. Boselli, D. Burgarella, J. Iglesias-Paramo2

& L. Tresse1: also at CFHT

2: also at IAA, Granada, Spain

Summary of the activities

• Main input from OAMP/LAM: GALEX & VVDS data, interpretation.

• Topic 1: Nearby Galaxies, physics of star forming galaxies

• Topic 2: Distant Galaxies, star formation characteristics

The GALEX missionP.I: C. Martin, Caltech, participation of CNES/ LAM

1.2 deg

ELAIS-S1, 12 000 secM31, mosaics

GALEX: A UV surveyor with a large field of view

The GALEX missionP.I: C. Martin, Caltech, participation of CNES/ LAM

GALEX satellite, launch: Avril 2003, still observing Imaging mode at 1530 Å (FUV) and 2315 Å (NUV),

spatial resolution ~5 arcsec

• All Sky Imaging Survey @ 20-21ABmag/14000 fields• Medium Imaging Survey @ 23 ABmag/1200 fields• Deep Imaging Surveys @ 25.5 ABmag/150 fields • Nearby Galaxies Survey: ~1000 galaxies

X-correlations with surveys at other wavelengths

GALEX sky coverage 10/02/2006

The VIMOS VLT Deep Survey

More than 220 galaxies observed simultaneously (march 2002)

VIMOS mounted at Nasmyth B focus of VLT Melipal

The VIMOS VLT Deep SurveyP.I.: O. Le Fèvre & G. Vettolani

• 16 deg2 in four separate fields• Imaging survey (CFHT, ESO) UBVRI-K• Spectroscopic survey: few thousands of

spectra @ R=250, redshift measurements

I band selection: shallow survey IAB= 22.5 mag and deep survey IAB=24 mag (2 deg2/1 field)

--> galaxies from z ~0 to z ~5 <z>=0.8

Multi-wavelengths analyses

Combining several wavelengths from ultraviolet to far infrared enables us to study:

• Current Star formation in an unbiased way• Dust obscuration• Star formation history • Environmental effects

In the nearby and more distant universe

Nearby Galaxies: star formation laws

Based on the Nearby Galaxies Survey of GALEX: UCM Madrid/OAMP-LAM Marseille

Boissier et al. 06

The star formation as seen in UV extends to significantly lower gas densities than in H: for low levels of SF the H radiation becomes stochastic (very low number of ionizing stars) whereas the UV radiation due to older stars in larger number shows no break

Nearby Galaxies: The effect of the environment on the evolution of galaxies

LAM/UCM Boselli et al. 06NGC 4569: a typical HI deficient, anemic Virgo galaxy Models for ram pressure stripping consistent with the observed profiles (from NIR to FUV). A method to age-date the interaction.

Nearby galaxies: other on-going projects

•The dwarf galaxy survey: P.I. R. Peletier Groningen/LAM/UCM/Nottingam/Padova Obs.

Observation of a UV selected sample of ~ 100 dwarf irregular and quiescent galaxies in the Virgo cluster and in the field in imaging mode : near-IR, H imaging, low- res. and 2D spectroscopy

Status: 48 night (5% of the whole telescope time) allocated in two semesters 2006 at WHT, TNG, INT, NOT; 12 nights allocated in the first

semester 2007. 2006 data under reduction

•SFH in normal late type galaxies: LAM/Padova ObsConstraining the star formation history of normal, late-type galaxies by comparing the UV to radio centimetric SED to the GRASIL model Status: work just started

Nearby universe: Understanding star formation and dust obscuration

GALEX/IRAS samples in the nearby universe: several hundreds of galaxies carefully selected

Several studies:

•Statistical analyses, IR/UV luminosity functions Buat et al. 06

•Star formation history and dust attenuation through SED fitting Burgarella et al. 05

•Dust attenuation analysis: Buat et al. 05, Panuzzo et al. 06, Inoue et al. 05

•Star formation estimations: Iglesias-Paramo et al. 05

Understanding dust obscuration in nearby galaxies: Panuzzo et al 06

•A MW extinction curve is consistent with the FTIR/FFUV vs FUV-NUV color: the age-dependent extinction reduces the presence of the 2175 A bump

•The wavelength dependence of the scattering albedo has also a strong impact on the FUV-NUV color (Inoue et al. 2005)

FTIR/FFUV measures the amount of dust attenuation

FUV-NUV color is sensitive to the wavelength dependance of

dust attenuation

Starbursts locus

Based on GRASIL models: Padova obs. /OAMP-LAM

Analyses of Spectral Energy Distributions of galaxies at z>0

1. GALEX/SPITZER-SWIRE: SED fitting of UV selected galaxies with GRASIL models

2. GALEX/SPITZER-MIPS: SED fitting of Lyman Break Galaxies at z~1

3. GALEX/VVDS/SWIRE: SED fitting of optically selected galaxies from z=0 to

z~5 --> Jakob Walcher talk

UV (rest-frame) selected galaxies from z~0 to z~1 with GALEX/SWIRE

Iglesias-Paramo et al. 07

• Templates:GRASIL models• Data: GALEX/ELAIS/SWIRE data UV vis NIR+MIR+FIR

UV (rest-frame) selected galaxies from z~0 to z~1 with GALEX/SWIRE

Total galaxy luminosityMstar

L du

st/L

UV

SF

R/M

sta

r

A diminution of dust attenuation in UV selected galaxies as z increases

The so-called downsizing also seen in a pure UV selection

Lyman Break Galaxies @ z~1 with GALEX/MIPS Burgarella et al. 06

FUV dropouts, z=0.9-1.3.

CDFS: photometric redshifts, optical photometry, IRAC and MIPS dataObserved wavelength A

Thank you for your attention and please listen to Jakob for the continuation of the

story….