1. Star formation at high redshift (2 < z < 7) Methods for deriving star formation rates UV continuum = ionizing photons (dust obscuration?) Ly  = ionizing photons (dust obscuration?) Far IR = bolometric (covering factor?) Radio continuum (synchrotron) = empirical (radio – FIR correlation?) Radio free-free/RRLs = ionizing photons (sensitivity, spectral confusion?) All relate mostly to massive stars (> 5 M _sun ) => total SFR depends on extrapolation of IMF, and temporal behavior

2. Cosmic (proper) time

3. Radio-FIR correlation: tightest correlation in extragalactic astronomy Separating FF – Synch is difficult Synch. Free-free Thermal dust M82

4. SKA in context z=8 EVLA

5. Cosmic ‘background’: ½ starlight reprocessed by dust

6. Evolution of space density of luminous QSOs (Fan et al. 2003) Madau-Lilly plot: evolution of cosmic star formation rate density

7. Galaxy populations at high redshift (2 < z < 7) Radio galaxies: only z > 0.5 galaxies before 90’s UV dropouts/Ly-break: broadband colors Ly  : narrow band imaging Submm: (sub)mm bolometer camera imaging QSO Hosts: HST, (sub)mm QSO absorption lines: metalicity evolution, parent galaxies z=0.3 to 2: EROs, faint blue, Butcher-Oemler,  Jy radio sources, ISO GRB hosts Pop III stars: early reionization by 100 M _sun stars in minihalos at z = 20?

8. z = 5.2 2000 10kpc High z radio galaxies (L _1.4 > 1e28 W/Hz) 10kpc z=0.057 1954 z=0.49 1980 z=3.8 1990

9. K-z relation: HzRGs = Giant Ellipticals z>8 radio galaxies?

10. Alignment effect: Jet-induced star formation? Clumpy morphologies => forming ellipticals? 1138-262 z=2.2

11. Alignement effect: Radio-Xray Radio-Ly  halo 18kpc

12. Clustering on Mpc scales around HzRGs (1138-262 z=2.2) => protoclusters?

13. Dusty radio galaxies at high z? Overdensity of submm galaxies?

14. UV dropouts/Ly break (Ly 

16. Star formation rates in Ly break galaxies Extinction uncorrected corrected

17. Correlation between extinction and SFR => L _UV is independent of SFR

18. Ly break galaxies = highly biased (ie. clustered) galaxy formation

19. Ly break galaxies with Ly  halos

20. SUBMM galaxies: dust obscured galaxy formation HDF - optical HDF – 850  m

21. Dust obscured star formation dominates at z>2? Submm galaxies: L _FIR = 1e12 to 1e13 L _sun => SFR = 100 to 1000 M _sun /yr M _dust = 1e8-9 M _sun

22. Magic of submm 350 GHz 250 GHz

23. Brightest mm source in HDF: K = 23.5

24. Radio photometric redshifts: two colors, or ‘drop- outs’

25. Redshift distribution

26. Next step: photometric redshifts

27. CO emission => M(H _2 ) = 1e10-11 M _sun

28. Submm galaxies

29. QSO host galaxies Most low z spheroidal galaxies have SMBH M _BH = 0.002 M _bulge => ‘Causal connection between SMBH and spheroidal galaxy formationn’ (Gebhardt et al. 2002)?

30. 30% of luminous QSOs have S _250 > 2 mJy  L_FIR > 7e12 M _sun Dust heating: starburst or AGN? 2322+1944 z=6.4 S _250 =5.5mJy

31. Radio-to-IR SED = M82

32. CO(1-0) w. VLA: L _FIR = 3e13 L _sun M(H _2 ) = 1e11 M _sun

33. A Molecular Einstein Ring: VLA 45 GHz observations of CO2-1 emission from the gravitationally lensed QSO 2322+1944 at z=4.12 (Carilli et al. 2003) Keck RbandVLA CO2-1 2”

34. Using the gravitational lens to probe sub-kpc scales in 2322+1944: A starburst disk surrounding a SMBH => coeval SMBH – galaxy formation? Optical QSO Starburst disk: molecular gas, dust, radio continuum

35. Starbursts in QSO host galaxies? 30% of luminous QSOs (M _B < -27) have L _FIR = 1e13 L _sun (independent of redshift) Z= 2 sample: All L _FIR luminous QSOs detected at 1.4 GHz, and in all cases ‘q’ consistent with star forming galaxy (2.3 +/- 0.3)

36. Questions Relationships between different high z galaxy types? Halos masses and end-products (spirals, ellipticals)? Is > 1000 M _sun /yr possible, sustainable (Heckman limit)? IMF: top heavy? Star formation in extreme environments (P=100xISM)? Timescales? Dust formation at z>6: >1e8 M _sun in < 0.7 Gyr? What fraction of high z galaxy formation is dust-obscured? Submm galaxies – redshift distribution? radio – FIR correlation: mechanism? vs. redshift? M-  relation – coeval SMBH and galaxy formation? QSO dust heating: star formation or AGN? L _FIR from S _250 ? X = gas mass to CO luminosity conversion? L _FIR to dust mass conversion? Pop III stars, minihalos, and first luminous objects: role of radio astronomy?