1. History of IGM bench-mark in cosmic structure formation indicating the first luminous structures Epoch of Reionization (EoR)

2. z=5.80 z=5.82 z=5.99 z=6.28 The Gunn Peterson Effect Fan et al 2003 Fast reionization at z =6.3 => opaque at _obs <0.9  m f(HI) > 0.001 at z = 6.3

3. Neutral IGM evolution (Gnedin 2000): ‘Cosmic Phase transition’ HI fraction DensityGas Temp Ionizing intensity Normalization: GP absorption, LCDM + z=4 LBGs, T _IGM 8 Mpc (comoving)

4. Large scale structure (10’s deg) = Thompson scattering at EoR   e =Ln _e   e = 0.17 => F(HI) < 0.5 at z=20 WMAP Large scale polarization of CMB (Kogut et al.) GP + WMAP => Reionization Process is complex, extending from z~20-6? (200-800 Million years after Big Bang)

5. Fan et al. 2002 Near-edge of reionization: GP Effect Fairly Fast: f(HI) > 1e-3 at z >= 6.4 (0.87Gyr) f(HI) < 1e-4 at z <= 5.7 (1.0 Gyr) Problem:  _Lya >> 1 for f(HI) > 0.001

6. Complex reionization example: Double reionization? (Cen 2002) Pop III stars in ‘mini-halos’ (<1e7 M _sun) ‘normal’ galaxies (>1e8M _sun)

7. Radio astronomical probes of the Epoch of Reionization and the 1 st luminous objects 1.Objects within EoR – Molecular gas, dust, star formation 2.Neutral IGM – HI 21cm emission and absorption Collaborators USA – Carilli, Walter, Fan, Strauss, Owen, Gnedin, Djorgovski Euro – Bertoldi, Menten, Cox, Omont, Beelen SKA ‘level 0’ science team – Briggs, Carilli, Furlanetto, Gnedin

8. MAMBO + IRAM 30m Max-Planck Bolometer array: 133 pixel bolometer camera at 300mK, single mode horns (Kreysa) Wide field  imaging and photometry at 250 GHz rms = 30’

9. 1. Wide -field imaging at 1.4 GHz: rms=7uJy, 1” res, FoV=30’ Astrometry => avoid confusion Imaging => AGN vs. Starburst, Lensing? cm-to-mm SEDs => redshifts, star formation rates unhindered by dust 2. Low order CO transitions at 20 to 50 GHz: rms < 0.1 mJy, res << 1” Gas excitation and mass estimates Gas distribution and dynamics, Lensing? Very Large Array

10. Plateau de Bure Interferometer Imaging high order CO lines at 90 to 230 GHz: rms < 0.5 mJy, res < 1” (15% of collecting area of ALMA)

11. Magic of (sub)mm 350 GHz 250 GHz L _FIR = 4e12 x S _250 (mJy) L _sun for z=0.5 to 8 SFR = 1400 x S _250 M _sun /yr M _dust = 1.4e8 x S _250 M _sun

12. SDSS + DPOSS: 700 at z > 4 30 at z > 5 7 at z > 6 M _B L _bol > 1e14 L _sun M _BH > 1e9 M _sun Hunt 2001 High redshift QSOs

13. QSO host galaxies – M _BH –  relation Most (all?) low z spheroidal galaxies have SMBH M _BH = 0.002 M _bulge  ‘Causal connection between SMBH and spheroidal galaxy formation’ (Gebhardt et al. 2002)?  Luminous high z QSOs have massive host galaxies (1e12 M _sun )

14. 30% of luminous QSOs have S _250 > 2 mJy, independent of redshift from z=1.5 to 6.4 L _FIR =1e13 L _sun = 0.1 x L _bol : Dust heating by starburst or AGN? MAMBO surveys of z>2 DPSS+SDSS QSOs 1148+52 z=6.4 1048+46 z=6.2 1e13L _sun Arp220

15. L _FIR vs L’(CO)  M(H_2) = X * L’(CO), X=4 (Milkyway), X=0.8 (ULIRGs)  Telescope time: t(dust) = 1hr, t(CO) = 10hr Index=1.7 Index=1 1e11 M_sun

16. highest redshift quasar known L _bol = 1e14 L _sun central black hole: 1-5 x 10 9 M sun ( Willot etal.) clear Gunn Peterson trough (Fan etal.) Objects within EoR: QSO 1148+52 at z=6.4

17. 1148+52 z=6.42: MAMBO detection S _250 = 5.0 +/- 0.6 mJy => L _FIR = 1.2e13 L _sun, M _dust =7e8 M _sun  3’

18. VLA Detection of Molecular Gas at z=6.419 46.6149 GHz CO 3-2 Off channels 50 MHz ‘channels’ (320 kms -1,  z=0.008) noise: ~57  Jy, D array, 1.5” beam  M(H _2 ) = 2e10 M _sun  Size < 1.5” (image),  Size > 0.2” (T _B /50K)^-1/2

19. IRAM Plateau de Bure confirmation FWHM = 305 km/s z = 6.419 +/- 0.001  (3-2) (7-6) (6-5) T kin =100K, n H2 =10 5 cm -3

20. VLA imaging of CO3-2 at 0.5” and 0.15” resolution  Separation = 0.3” = 1.7 kpc  T _B = 20K = T _B (starburst )  Merging galaxies?  Or Dissociation by QSO? rms=50uJy at 47GHz  CO extended to NW by 1” (=5.5 kpc) tidal(?) feature  T _B = 3 K = Milky way

21. Phase stability: Fast switching at the VLA 10km baseline rms = 10deg

22. 1148+52: starburst+AGN?  SFR(>5 M _sun ) = 1400 M _sun /year => host spheroid formation in 5e7 yrs at z > 6?  SMBH formation: n x 2.4e7 yr (Loeb, Wyithe,…) => Coeval formation of galaxy/SMBH at z>6? S _1.4 = 55 +/- 12 uJy IRAS 2Jy sample (Yun+) 1148+52 1048+46

23. M( dust ) = 7e8 M _sun M( H _2 ) = 2e10 M _sun M _dyn (r=2kpc) = 4e10 (sin i) -2 M _sun M _BH = 3e9 M _sun M _BH –  => M _bulge = 1.5e12 M _sun Gas/dust = 30, typical of starburst Dynamical vs. gas mass => baryon dominated? Dynamical vs. ‘bulge’ mass => M –  breaks-down at high z? Or face-on (i < 9deg)? 1148+52: Masses

24. Cosmic (proper) time  T _univ

25. Age of universe: 8.7e8 yr C, O production (3e7 M _sun ): 1e8 yr Fe production (SNe Ia): few e8 yr (Maiolino, Freudling) Dust formation: 1.4e9yr (AGB winds) => dust formed in high mass stars/SNR (Dunne et al.. 2003) ? => silicate grains? => Star formation started early (z > 10)?  Timescales

26. Cosmic Stromgren Sphere Accurate redshift from CO: z=6.419 optical high ionization lines can be off by 1000s km s -1 Proximity effect: photons leaking from 6.32<z<6.419 z=6.32 Ionized sphere around QSO: R = 4.7 Mpc ‘time bounded’ Stromgren sphere: t _qso = 1e5 R^3 f(HI)= 1e7yrs White et al. 2003

27. Loeb & Rybicki 2000

28. Constraints on neutral fraction at z=6.4  GP => f(HI) > 0.001  If f(HI) = 0.001, then t _qso = 1e4 yrs – implausibly short? (see also J1030+0524 z=6.28, J1048+46 z=6.23 using MgII lines)  Probability arguments suggest: f(HI) > 0.1 at z=6.4 – much better limit than GP Wyithe and Loeb 2003 f _lt = 1e7 yr

29. Gravitational Lensing?  CO 3-2 double source, 0.3” separation => strong lensing?  Keck near IR imaging: point source < 0.5” at K (Djorgovski)  HST/ACS imaging: point source < 0.3” (Richards 2004)  Radio continuum: Foreground cluster (30x over-density) at z=0.05 => magnification by 2x? 1148+5251

30. Fan et al. 2002 Near-edge of reionization: GP + Strom. Spheres Very Fast? f(HI) > 1e-1 at z >= 6.4 (0.87Gyr) f(HI) < 1e-4 at z <= 5.7 (1.0 Gyr)

31. Gas and dust in the first galaxies Luminous (star forming?) galaxy: Far IR luminosity = 1e13 L sun at z=6.42 Merging(?) galaxy: Molecular gas mass = 2x10 10 M _sun, M _dyn = 4e10 (sin i) -2 M _sun Early enrichment of heavy elements and dust produced in the first stars => star formation commenced at 0.4 Gyr after the big bang Coeval formation of SMBH + stars in earliest galaxies (break-down of M-  at high z?) Cosmic Stromgren sphere of 4.7 Mpc => ‘witnessing process of reionization’ t _qso = 1e7 * f(HI) yrs ‘fast’ reionization: f(HI)>0.1 at z=6.4?

32. J1048+4637: A second FIR-luminous QSO source at z=6.2 3.0 +/- 0.4 mJy => L _FIR = 7.5e12 L _sun M _dust = 4e8 M _sun

33. Cloverleaf z=2.56, Grav. Lens mag. 11x VLA detection of HCN emission at 22 GHz => n(H _2 ) > 1e5 cm^-3 (vs. CO n(H _2 ) > 1e4 cm^-3) (Solomon, vd Bout, Carilli)

34. ALMA 1hr Sensitivity of future arrays: Arp 220 vs z (FIR = 1e12 L _sun ) EVLA 100hr

35. Redshifts for obscured/faint sources: wide band (16 - 32 GHz) spectrometers on LMT/GBT (Min Yun 2004) L _FIR = 1e13 L _sun

36. Z=10 lensed star forming galaxy? (Pello 2004) L _app = 4e11 L _sun + LBG dust correction (5x) => L _FIR = 2e12L _sun S _250 = 0.6 mJy => 5  ALMA detection in 1 minute! S (CO 4-3 at 42 GHz) = 0.06 mJy => 5  EVLA detection in 15hr

37. Studying the pristine IGM beyond the EOR: HI 21cm observations with the Square Kilometer Array and LOFAR SKA: A/T = 20000 m^2/K =>  Jy at 200 MHz

39. Low frequency background – hot, confused sky Eberg 408 MHz Image (Haslam + 1982) Coldest regions: T = 200  z)^2.6 K

40. Global HI signature in low frequency spectra (Gnedin & Shaver 2003) double fast 21cm ‘fluctuations’ at 1e-4 wrt foreground

41. HI 21cm Tomography of IGM Zaldarriaga + 2003 z=1297.6   T _B (2’) = 10’s mK  SKA rms(100hr) = 4mK  LOFAR rms (1000hr) = 80mK

42. Power spectrum analysis Zaldarriaga + 2003 PAST LOFAR SKA Z=10 129 MHz 2deg1arcmin

43. 1422+23 z=3.62 Womble 1996 N(HI) = 1e13 -- 1e15 cm^-2, f(HI/HII) = 1e-5 -- 1e-6 => Before reionization N(HI) =1e18 – 1e21 cm^-2 Cosmic Web after reionization = Ly alpha forest (  <= 10)

44. Cosmic web before reionization: HI 21cm Forest ( Carilli, Gnedin, Owen 2002) SKA ‘observations’ of 21cm absorption before the EOR (A/T = 2000 m^2/K, 240hrs, 1kHz) Mean optical depth (z = 10) = 1% = ‘Radio Gunn-Peterson effect’ Narrow lines (  = few %, few km/s) = HI 21cm forest (  <= 10), 10/unit z at z=8 Mini-halos (  = 100) (Furlatto & Loeb 2003) Primordial disks: low cosmic density (0.001/unit z), but high opacity => fainter radio sources (GRBs?) Z=10 Z=8 20mJy

45. Radio sources beyond the EOR? Radio loud QSO fraction = 10% to z=5.8 (Petric + 2003) Models => expect 0.05 to 0.5 deg^-2 at z> 6 with S _151 > 6 mJy (out of 100 total) 2240 at z > 6 1.4e5 at z > 6 S _151 > 6mJy Carilli + 2002 Haiman & Hui 2004

46. Terrestrial interference 100 MHz200 MHz GMRT 230 MHz 0924-220 z=5.2

47.  Continuum point source = 0.55 Jy  Noise limited spectra:  =5.5 mJy/channel  HI 21cm absorption at z=5.200?  = 4%,  v = 130 km/s N(HI) = 9e20 (T s /100K) cm^-2

48. SKA timeline 2004 Science case: “Science with the SKA” Carilli & Rawlings, New Astron. Rev. 2004-7 demonstrator development major external review (2006) submit funding proposals for a 5% demonstrator 2006site selection: Autralia, USA-SW, South Africa, China 2008 selection of technical design (may be a combination); start construction of 5% demonstrator on chosen site 2009 submit funding proposals for full array 2012 start construction 2020complete construction Projected cost: 1 G$

49. Radio astronomy – Probing the EoR Study physics of the first luminous sources (limited to near-IR to radio wavelengths) Currently limited to pathological systems (‘HLIRGs’) EVLA and ALMA 10- 100x sensitivity is critical for study of ‘normal’ galaxies SKA is the only means to study the neutral IGM z 

50. Ultimate goal: Far side of the moon?  No RFI  No ionosphere  Cheap, ‘dirty’ antennas  No moving parts 130MHz