1. A Wide Area Survey for High- Redshift Massive BzK Galaxies X.Kong, M.Onodera, C.Ikuta (NAOJ), K.Ohta (Kyoto), N.Tamura (Durham), A.Renzini, E.Daddi, L. Da Costa (ESO), A.Cimatti (Arcetri), T.Broadhurst (Tel’Aviv), L.F.Olsen (Cote d’Azur) N. ARIMOTO (NAOJ) Kong et al. (2006) ApJ 638, 72

2. EIS Deep 3a Survey We have undertaken a fairly deep, wide-field imaging with the Subaru/Suprime-Cam of two fields of 900 arcmin 2 each for part of which near-IR data are available from ESO NTT observations. EIS3a-F (Subaru/NTT, Ks=20.8) 320 arcmin 2 Daddi-F (Subaru/NTT, Ks=19.0) 600 arcmin 2 The prime aim of this survey is to understand how and when the present-day massive galaxies formed. To this end, the imaging observations have been optimized for the use of optical/near-infrared multi-colour selection criteria to identify both star forming (sBzKs) and passive galaxies (pBzKs). Kong et al. (2006) ApJ 638, 72

3. Subaru/Sup-Cam Observation Daddi Field RA=14:49:29, DEC=09:00:00 (J2000.0) Subaru/Suprime-Cam BIz’: 2003/03/02-04 WHT R : 1998/03/19-21 NTT/SOFI K : 1999/03/27-30 BRIz’ (940 arcmin 2 ) 3σ in 2”(AB) B(AB)=26.59 R(AB)=25.64 I(AB)=25.62 z’(AB)=25.31 K (600 arcmin 2 ) 3σ in 2”(AB) Ks(AB)=20.91

4. 940arcmin 2 600arcmin 2

5. Subaru/Sup-Cam Observation ESO Imaging Survey (EIS Deep 3a) Field RA=11:24:50, DEC=-21:42:00 (J2000.0) Subaru/Suprime-Cam BRIz’: 2003/03/02-04 NTT/SOFI JK : 2002/03/28-31 BRIz’ (940 arcmin 2 ) 3σ in 2”(AB) B(AB)=27.46 R(AB)=26.87 I(AB)=26.56 z’(AB)=26.07 JK (320 arcmin 2 ) 3σ in 2”(AB) J(AB)=23.40, Ks(AB)=22.70

6. 940arcmin 2 320arcmin 2

8. High-z galaxies Deep 3a field Star-forming galaxies at z>1.4 (sBzKs) Old galaxies at z>1.4: (pBzKs) stars BzK=(z-K)-(B-z)>-0.2 （ｚ－ K)>2.5 Daddi et al. (2004) ApJ 617, 746

9. SEDs of sBzKs and pBzKs

10. star-forming passive low-z high-z Photometric Redshift

11. Spectroscopic Redshifts (VLT) Daddi et al. (2006)

12. pBzK(ERO) sBzK sBzK sBzK ERO ERO

13. Star/Galaxy Separation (z-K) AB -0.3(B-z) AB <-0.5

14. 387 sBzK121 pBzK 108 sBzK48 pBzK 513 ERO 337 EROs

15. Photometric Redshift (EROs)

16. Photometric Redshift (sBzKs)

17. Photometric Redshift (pBzKs)

18. Number Counts of sBzKs, pBzKs, and EROs EROs galaxies sBzKs pBzKs

19. Two Point Correlation Functions w(Θ) Daddi-FDeep 3a-F Landy & Szalay (1993)

20. Angular Clustering Amplitude

21. Physical Properties of sBzKs and pBzKs Supposing ～ 2 for sBzKs, we have derived their physical properties, such as the reddening, star formation rate, and the stellar mass. (While errors by a factor of 2 or more may affect individual estimates, the average quantities should be relatively robust.) Reddening : E(B-V)=0.25(B-z+0.1) AB ←UV Continuum slope (Calzetti law) SFR : SFR(Mo/yr)=L 1500 [erg/s/Hz]/8.85x10 27 Stellar Mass : log(M * /10 11 Mo)=-0.4(K tot -20.14 Vega )

22. The filled area is the histogram for sBzKs which associated with X-ray sources (25%). The dashed lines are for the stellar mass histograms of pBzKs.

25. MAMBO & Spitzer (MIPS) Observations of sBzKs at z ～ 2 Dannerbauer et al. (2006) ApJ 637, L5 (Poster 14 Dannerbauer) BB zz

26. IR SFR ～ UV SFR sBzKs sBzKs(GOODS-N) Local ULIRGs SMGs

27. Contribution of sBzKs and pBzKs to Stellar Mass Density at z=2 25% AGN Number density of pBzKs with M * >10 11 Mo over the range 1.4<z<2.0 (1.8±0.2)x10 -4 Mpc -3 Local value of massive ellipticals at z=0 9x10 -4 Mpc -3 (Baldry et al. 2004) logρ * (total)=7.7 Mo/Mpc 3 logρ * (total)=7.86 Mo/Mpc 3 (1.5<z<2.0, Fontana et al 04) logρ * (total)=7.65 Mo/Mpc 3 (2.0<z<2.5, Fontana et al 04) logρ * (total) ～ 7.5 Mo/Mpc 3 (@ z ～ 2, Dickinson et al 03) 20%±7% of massive (M * >10 11 Mo), passively evolving galaxies at z=0.

28. Summary (I) – Number Counts BzK selection is a quite powerful way to separate high-z galaxies such as sBzKs, pBzKs and EROs at 1.4<z<2.5. 1)Down to the K-band limit of the survey the log of the number counts of sBzKs increases linearly with the K-magnitude, while that of both EROs and pBzKs flattens out by K vega ～ 19. EROs are in a modest redshift shell (z ～ 1), while pBzKs are also in a relatively narrow redshift shell but at higher redshift (z ～ 1.5). sBzKs are drawn from a large range of redshifts, and their relative numbers increase sharply with redshift.

29. Summary (II) - Clustering 2) The clustering properties of EROs and sBzKs are very similar, clustering amplitudes ～ 10 times higher than generic galaxies in the same magnitude range. This suggests an evolutionary link between sBzKs at z ～ 2 and EROs at z ～ 1, with star formation on sBzKs quenching by z ～ 1 thus producing passively evolving EROs. The clustering amplitude of pBzKs is even higher than that of sBzKs and EROs, suggesting that quenching epoch of star formation in massive galaxies depends on environmental density.

30. Summary (III) – Physical Properties 3) sBzK galaxies (K Vega <20) have median reddening E(B-V) ～ 0.40, average SFR ～ 190 Mo/yr, typical stellar mass ～ 10 11 Mo, and ～ solar metallicity (Poster 44 Onodera). The high SFRs, large masses and high metallicities of sBzKs suggest that these z ～ 2 star forming galaxies are the precursors of z=1 passive EROs and z=0 early-type galaxies. Mambo/MIPS observations suggest sBzKs are post ULIRGs.

31. Summary (IV) – Number Density 4) The number density of massive pBzKs (K Vega 10 11 Mo) is about 1/5 of similarly massive early-type galaxies at z=0. The quenching of star formation in massive star-forming galaxies must result in a significant growth since ～ 1.7 in the number of massive, passive galaxies. We argue that most of this star-formation quenching is likely to take place between z ～ 2 and z ～ 1.

32. Massive Early-type Galaxies Evolutionary Tracks (M * >10 11 Mo) z ～ 0 z ～ 1 z ～ 2 z>2 Early-type Galaxies Passive EROs sBzKs pBzKs ? sRjLs number density 1/5 number density 1/2 number density 1 E(B-V) ～ 0.4 SFR ～ 190Mo/yr Z ～ Zo strong clustering very very strong clustering SMGs 40-200Myr 0.5-1Gyr irregular morphology Passive EROs DustyEROs