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PI : Chris Martin (Caltech). PI : O. LeFèvre (Marseille) G. Vettolani (Bologna). THE GALEX-VVDS DEEP SURVEYS : Evolution of the Far UV luminosity Function and Density (+ SFR) up to z=1.5. Stéphane Arnouts David Schiminovich Olivier Ilbert and VVDS and GALEX teams.
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PI : Chris Martin (Caltech) PI : O. LeFèvre (Marseille) G. Vettolani (Bologna) THE GALEX-VVDS DEEP SURVEYS : Evolution of the Far UV luminosity Function and Density (+ SFR) up to z=1.5 Stéphane Arnouts David Schiminovich Olivier Ilbert and VVDS and GALEX teams
One of the principal goal of GALEX • Evolution of the SFR density up to z=1.5 • UV sensitive measurement of the ongoing Star Formation • Used to derive SFRD: • locally (z<0.2 , FOCA) • at high-z (z>2.5, in optical band) • GALEX fills the gap where most of the SFR evolution is seen • Required • DEEP and WIDE GALEX observations • DEEP and WIDE optical spectro-photometry observations
Outline of the talk : • Results from a PILOT STUDY done in the 2hr field : • GALEX Deep obervations • VVDS Deep spectroscopy and photometry • Spectroscopic sample : • Evolution of the FUV LF and LD • Implication in the SFR history • Morphology of a sub-sample of UV luminous galaxies • Recent Photo-z analyses : • Combined dataset : VVDS+CFHTLS+SWIRE
GALEX-02hr field Texp= 52765 sec <E(B-V)>=0.027 Used area : FUV+NUV color image AAS 72.07 - DS
NUV < 24.5. Completeness correction with HST counts (Gardner et al. 2000) GALEX Galaxy Number counts
The 2hr field combined dataset VVDS : BVRI (JK) VVDS : spectroscopy IAB=24 GALEX • AND • CFHTLS : ugriz • SWIRE : 3.6 to 8m • +24m (section photo-z) Spectroscopic Area : 0.46 deg2
GALEX - OPTICAL matches NUV band5” PSF AAS 72.07 - DS
GALEX - OPTICAL matches B band1” PSF AAS 72.07 - DS
GALEX - OPTICAL matches PSF=5’’ but good astrometry Counterparts searched in a distance = 4’’ : ast= 0.7’’ • ALL UV sources have an optical counterparts • NUV<24.5 ~50% have a single optical counterparts • NUV<24.5 ~35% have two optical counterparts • NUV<24.5 ~15% have more than two optical counterparts
GALEX - OPTICAL matches • Preliminary Analysis : • UV sources matched with the closest OC • which is in 90% cases the brightest one • Impact of the blends based on : • -1 : expected colors from single match • -2 : apportion the UV flux among the multiple OCs • using Sutherland & Sanders (1992) method • <UV flux> overestimated by • 0.25 mag for 2 OCs • 0.50 mag for multiple OCs
GALEX with VVDS spectroscopy ~1100 Zspec 19.5<NUV<24.5 ~15% UV sample
Color distribution Saturation in I Spectro : Good sampling of UV sources. Saturation : 95% at z<0.2 (SDSS) IAB>24: only 4% Limit spectro
Redshift distribution LF with secure redshifts Unique OC <= 2 Ocs full sample
FUV Luminosity Function with ~1000 Z-spectro (Arnouts, Schiminovich, Ilbert et al. 2005) FUVabs from NUV mag LF estimators : Vmax, C+, SWML, STY using ALF tool (Ilbert et al., 2004) Weight to account for : Spectroscopic strategy NUV counts completeness Local GALEX LF (Wyder et al., 2005) Strong evolution from 0<z<1.2 (GALEX)
FUV Luminosity Function at higher z (Arnouts, Schiminovich, Ilbert et al. 2005) Zphot from HDF N+S (Arnouts et al., 1999 & 2002) z to be FUV rest-frame : 1.75<Z<2.25 with F450<27 2.40<Z<3.40 with F606<27 1700A LF @z=3 (Steidel et al., 1999) Trend continues to z=3 (HDF)
Evolution of the FUV Luminosity Function Arnouts, Schiminovich, Ilbert et al (2005) Possible evolution in slope Significant evolution 0 < z < 1 : M*= 2 mag (or x6 in L*) 1 < z < 3 : M*= 1 mag
GALEX AIS-MIS : Wyder et al GALEX DIS : This work Sum of (L).L.dL Using Vmax LF HDF : Arnouts et al (99, 02) Steidel et al (1999) Integration of STY fit up to L=0 Evolution of FUV Luminosity DensitySchiminovich, Ilbert, Arnouts et al. (2005) LD using ALF tool (1+z)3.5 (1+z)2.5 (1+z)1.5 (1+z)2.5 luminosity density evolution since z~1 Continued slow evolution 1<z<3
UV Luminous Galaxies (UVLGs)(DS, Ilbert, Arnouts et al) • Luminosity density of • UV luminous: L>0.2 L*(z=3) • “LBG-like” galaxies shows • dramatic evolution: (1+z)5 • Steeper than QSO • LD evolution • (Boyle + Madau et al) • UVLGs produce a • significant fraction of LD • at z = 1 (25%) Total (1+z)2.5
Sizes of extreme UV-luminous galaxies (Slide courtesy of D.S.) Local Measurement: GALEX-SDSS (Heckman, Hoopes et al, 2005) LFUV,bol > 2x1010 Msol SFR 5-50 Msol/yr Local : u-band r1/2 (circles) Compact galaxies may be LBG analogs with high SFR/area and SFR/<SFR> Large Compact 0.55<z<0.8 : COSMOS M. Zamojski &D. Schiminovich V-band r1/2 (squares) r1/2 consistent with local sample & Locus slightly higher than for LBGs AAS 72.07 - DS
(Slide courtesy of D.S.) Large UV Luminous Galaxies (UVLGs)r50~10 kpc0.55<z<0.8 AAS 72.07 - DS
(Slide courtesy of D.S.) Compact UV Luminous Galaxies (UVLGs)r50~2.5 kpc0.55<z<0.8 AAS 72.07 - DS
Dust attenuation correctionSchiminovich, Ilbert, Arnouts et al. (2005) Using UV slope: AFUV = f() FWHM()=1.4 ()=0.4 (Meurer et al.,1999Kong et al., 2004) Full sample consistent with - local FUV sample (Treyer et al., 2005) - high-z sample (Adelberger, 2000)
Uncorrected SFR vs. Z Schiminovich, Ilbert, Arnouts et al. (2005) Conv. LFUV to SFR (Kennicutt, 1998) No dependence of dust attenuation AFUV with SFRuncor NUV<24.5 NUV <26 (UDIS) L*(z) As a consequence
Corrected SFR vs. Z Schiminovich, Ilbert, Arnouts et al. (2005) Conv. LFUV to SFR (Kennicutt, 1998) + AFUV (Meurer et al., 1999) NUV=24.5 AFUV 4.0 2.5 1.5 0.5 0. Paucity of low AFUV galaxies with high SFRcor - Large scatter in the measured AFUV - Dust attenuation law M99 relation may overestimate AFUV for star-forming galaxies
Evolution of the SFR Densityuncorrected and dust-corrected (hatched region) Wilson et al (2002) Lilly et al (1996) Sullivan et al (2000) Brinchmann Tresse and Maddox Perez-Gonzalez Gronwall Consistent with H measurements Uncorrected SFRD (1+z)2.5 0<z<1.5 : =2.5 1.2<z<3 : =0.5 Corrected SFRD Meas <AFUV>=1.8 Min AFUV=1.0 (local UV sample Buat et al. 2005)
Photometric Reshifts in F02 fieldworks byIlbert , Arnouts, Budavari et al Photometry used : VVDS : (U)BVRI(JK) CFHTLS : ugriz SWIRE : 3.6 +4.5m VVDS : (U)BVRI (JK) GALEX Classification in Galaxy/Star/QSO FUV LF with photo-z for a large sample Z photometric Area : 0.65 deg2
Photometric Reshifts of UV galaxies in F02 field Colors : galaxy types Filled circles : 1 OC Open triangles : n OCs No systematic 0<z<1.2 Small scatter : =0.04 Secure Zspec : 949
Photometric Reshifts of UV galaxies in F02 field Colors : galaxy types Filled circles : 1 OC Open triangles : n OCs No systematic 0<z<1.2 Small scatter : =0.05 Small number of outliers All Zspec : 1127 VVDS : (U)BVRI (JK)
Color-color checks vs classification (NUV-B) vs (B-I) VVDS : (U)BVRI (JK) Star/galaxy separation Galaxies below the line
Color-color checks vs classification VVDS : (U)BVRI (JK) (FUV-NUV) vs (B-I)
Color-color checks vs classification (B-I) vs (3.6-4.5) VVDS : (U)BVRI (JK) Same QSOs and Stars regions for spec. and phot.
Galaxy Redshift distribution VVDS : (U)BVRI (JK)
FUV Luminosity Function with ~6000 Z-photo At z=1: no constraint on slope Consistent with =-1.6
FUV Luminosity Function Zspec vs Zphot • Consistent with LF(spec) • Smaller errorbars • At 0.2<z<0.4 : • constraint on M*
FUV Luminosity Function Zspec vs Zphot No evolution in 0<z<0.8 Fixed Consistent M*(z) evolution
Galaxy “Type” classification with Zspec (Arnouts, Schiminovich, Ilbert et al., 2005) Kinney et al;, 1996 • - Small number of galaxies • redder than Sb • Degeneracy between • old syst. and dusty SB Poggianti et al 1997 (NUV-R) correlated with SFRcurrent/ <SFR>past(Salim et al. 2005) : Galaxy SF history (B-I) correlates with (NUV-R) : (B-I) as a crude proxy for galaxy type Apply to the Zphot sample
Galaxy “Type” classification with Zphot Type fraction vs Z (FUV<22, z<0.2) Increase of the unobscured SB class from z=0 to 1
Galaxy “Type” LF with Zphot Similar evolution for the two reddest classes Stronger evolution of the SB class wrt red ones
Galaxy “Type” LF with Zphot (z)~constant per type 2 Red classes : -0.9< <-1.2 SB class : -1.5< <-1.8 Modest luminosity evolution of SB class wrt reddest classes Number density evolution of the SB class
Conclusion • GALEX-VVDS PILOT STUDY • Global evolution of the FUV light of galaxies in 0<z<1.5 • and LFs per type: strong increase in density of SB class • Constraint on the evolution of the SFRD (uncorr.,corr.) • A new class of UVLG at 0.5<z<1 (LBG analogs) • in easy reach for optical follow-up • NEAR FUTUR • GALEX-VVDS-SWIRE : nice combined science • (zphot, dust law, SFR vs Mass, AGN evolution,...) • More deep field and a few deeper ( lower SFR sensitivity) • SF sites vs LSS (UV / optical-IR cross-correlation)
Conclusion • GALEX-VVDS PILOT STUDY • Global evolution of the FUV light of galaxies in 0<z<1.5 • and LFs per type: strong increase in density of SB class • Constraint on the evolution of the SFRD (uncorr.,corr.) • A new class of UVLG at 0.5<z<1 (LBG analogs) • in easy reach for optical follow-up • NEAR FUTUR • GALEX-VVDS-SWIRE : nice combined science • (zphot, dust law, SFR vs Mass, AGN evolution,...) • More deep field and a few deeper ( lower SFR sensitivity) • SF sites vs LSS (UV / optical-IR cross-correlation)