Renzini Ringberg The cosmic star formation rate from the FDF and the Goods-S Fields R.P. Saglia – MPE reporting work of/with R. Bender, N. Drory, G. Feulner, A. Gabasch, U. Hopp, M. Pannella, M. Salvato Introduction The Fors Deep and Goods-S Fields Luminosity functions Star Formation Rates and stellar densities (up to z=5) Morphologies (up to z=1) Conclusions Gabasch et al. 2004, A&A, 421, 41; Drory et al. 2005, ApJL; 619, L131; Gabasch et al. 2004, ApJL, 616, L83; Pannella et al. 2005, ApJL, in prep

Renzini Ringberg Introduction Bouwens et al “Madau plot”: Star Formation Rate history of the Universe Open questions: Cosmic variance Galaxy selection Faint-end contribution Role of Dust Morphology split Hernquist & Springel 2003

Renzini Ringberg The FDF and Goods-S fields Heidt et al. 2003, A&A, 398, 49Salvato et al. 2005, in prep U…K photometry, >7 times larger field than HDF

Renzini Ringberg Photometric redshifts Gabasch et al. 2004, A&A, 421, spectra SED template fitting Bender et al. 2005

Renzini Ringberg Luminosity Functions at 1500 Gabasch et al. 2004, A&A, 421, 41 Good agreement with previous LF down to the mag limit. a = a = -1.6 excluded at 2 s level z=0.6 z=1.3 z=2.5 z=4.5

Renzini Ringberg Evolution of the LFs Steidel et al. 1999

Renzini Ringberg The UV-luminosity density and SFR (no correction for dust) The extrapolation to L=0 amounts to 2-20% for the FDF magnitude limits!

Renzini Ringberg The SFR in the FDF Gabasch et al. 2004, ApJL 616, L83 No difference with I or B catalogues Dust Adelberger & Steidel Factor 5-9 correction At z>3 B drop-outs

Renzini Ringberg The SFR in FDF and GOODS-S

Renzini Ringberg Stellar masses Photoz + BC03 2 components (main+burst) Age, metallicity Dust, component ratio Errors in log M/L: 0.1<d log M/L<0.2

Renzini Ringberg Dust and SFR GALEX Schiminovich et al. 2005, ApJL 619, L47 SPITZER Egami et al ApJS 154, 130 Stellar mass Factor GALEX confirms SFR at z<1 SPITZER shows that ULIRG cannot dominate

Renzini Ringberg Morphologies Analysis of HST ACS images: FDF: 4 pointings, 1 orbit per pointing in the F814W filter 40 minutes exposures, I(AB, 10 sigma) = 26 Goods-S: 3/2.5/2.5/5 orbits in the BViz filters 100/80/80/160 minutes exposures BViz(AB, 10 sigma) = 27/27.2/26.5/26.5 Visual Classification performed by U. Hopp Quantitative morphology performed by M. Pannella, fitting the 2D images with PSF convolved with the Gim2D and Galfit packages, I=24/24.5 for FDF (F814W) and Goods (F775W), z<1.15 Sersic Profiles

Renzini Ringberg Quality Control Mock catalogue of 4000 objects for each of the two fields, with 22.5<I(AB)<Ilim 0.05”<Re<2” 0.5<n<6 0<ellipticity<0.7

Renzini Ringberg Visual Morphology Final catalogue with 1647 objects, 90 sq. arcmin area, z<1.15, with Masses, redshifts, luminosities, dimensions, profiles

Renzini Ringberg Mass completeness At any redshift objects with the highest M/L ratio are cut out of the sample because of the flux limit. SSP from BC03 formation at z=10 no dust sub-solar metallicity passively aging  Largest M/L  lowest detectable M

Renzini Ringberg Morphological stellar mass functions The mass at which disks becomes dominant is increasing with z Disks dominate at all redshifts the low mass end of the MF In good agreement with Bundy et al. (2005) at the same z and Bell et al. (2003) at z=0 “Morphological Downsizing” ?

Renzini Ringberg Stellar mass density evolution The total mass density at z=1 is 50% lower than at z=0 The morphological mix evolves dramatically with redshift Mass density moves from disks to bulges from z=1 to z=0 In agreement with Bundy et al. 2005, Brinchmann & Ellis 2000

Renzini Ringberg Two scenarios Option 1: the 50% “missing stellar mass” at the high mass is provided by in situ star formation. The morphological mass density evolution from disks to bulges is driven by secular evolution. Option 2: The star formation rate is not high enough to explain the missing stellar mass. Merging of (smaller mass) galaxies must play a key role. Merging of the massive disk systems explains the morphological evolution.

Renzini Ringberg Specific star formation rates Only 2 objects would be able to double their masses to z=0 assuming constant SFR Almost all the sample would be unable to increase its original mass by more than 30% with constant SFR in situ  Option 2 favoured

Renzini Ringberg Conclusions: the SFR SFR estimates from B, I and I+B catalogues agree well and are confirmed by GALEX at z<1 SFR estimate from K catalogue is lower by 0.3 dex because it is missing galaxies with L<L* Cosmic variance < 0.1 dex Bright galaxies with L>L* produce 1/3 of the total SFR Previous estimates of the SFR are too high by a factor of 2 because the faint-end slope of the LF has been overestimated Dust correction is ~ factor 3 Complete census of galaxies nearly reached: SPITZER The SFR is roughly constant up to z=4 and declines slowly beyond

Renzini Ringberg Conclusions: Morphologies The morphological mix evolves strongly with redshift The stellar mass density moves from disks (at z=1) to bulges (at z=0) Merging must have an important role

Renzini Ringberg The dust correction Using a factor 6.5 dust correction (or A28000=2):

Renzini Ringberg The Sersic profile