1. History of IGM bench-mark in cosmic structure formation indicating the first luminous structures Epoch of Reionization (EoR) C.Carilli (NRAO) Cool Univ Oct 2004 ionized Neutral F(HI)=1 Ionized F(HI)=1e-5

2. Gunn-Peterson effect Barkana and Loeb 2001

3. 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

4. Neutral IGM evolution (Gnedin 2000): ‘Cosmic Phase transition’ at z=6 to 7 Log (HI fraction) DensityGas Temp Ionizing intensity Normalization: GP absorption, LCDM + z=4 LBGs, T _IGM 8 Mpc (comoving)

5. Thompson scattering at EoR   e = 0.17 => F(HI) < 0.5 at z=17 Extended period of reionization: z=6 to 15? WMAP Large scale polarization of CMB (Kogut et al.) 20deg

6. 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)

7. Cen 2002 Recombination time vs. Hubble time Stellar fusion produces 7e6eV/H atom, while reionization requires 13.6eV/H atom =>Need to process only 1e-5 of baryons through stars to reionize the universe z>8: t _rec < t _H

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

9. Limitations of current measurements: CMB polarization: --  _e = Ln _e   e = integral measure through universe => allows many reionization scenarios Gunn-Peterson effect: --  _Lya >>1 for f(HI)>0.001 -- High z universe is opaque to optical observers ( _obs <0.9  m)

10. The Cool Universe: m/cm/mm probes of the Epoch of Reionization and the 1 st luminous objects 1.CMB large scale polarization 2.Objects within EoR – Molecular gas, dust, star formation 3.Neutral IGM – HI 21cm emission and absorption Collaborators USA – Carilli, Walter, Fan, Strauss, Owen, Gnedin Euro – Bertoldi, Cox, Menten, Omont, Beelen SKA Key Program science team– Briggs, Carilli, Furlanetto, Rawlings Science with the Square Kilometer Array (NAR, Carilli & Rawlings) http://www.aoc.nrao.edu/~ccarilli/CHAPS.shtml

11.  IRAM 30m + MAMBO: sub-mJy sens at 250 GHz + wide fields  IRAM PdBI: sub-mJy sens at 90 and 230 GHz + arcsec resol.  VLA: uJy sens at 1.4 GHz  VLA: < 0.1 mJy sens at 20-50 GHz + 0.2” resol.

12. Magic of (sub)mm L _FIR = 4e12 x S _250 (mJy) L _sun for z=0.5 to 8

13. SDSS + DPOSS: 700 at z > 4 30 at z > 5 9 at z > 6 M _B L _bol > 1e14 L _sun M _BH > 1e9 M _sun York et al 2001; Fan et al High redshift QSOs

14. 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 )

15. 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

16. 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 1e3 M _sun /yr High-z sources

17. 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

18. 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’

19. 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)

20. 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 Typical of starburst nucleus

21. VLA imaging of CO3-2 at 0.4” 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

22. 1148+5251: radio-FIR SED  Star forming galaxy characteristics: radio-FIR SED, L’ _CO /FIR, CO excitation and T _B => Coeval starburst/AGN: SFR = 1000 M _sun /yr  Stellar spheroid formation in few e7 yrs = e-folding time for SMBH => Coeval formation of galaxy/SMBH at z = 6.4 ? S _1.4 = 55 +/- 12 uJy 1048+46 Beelen et al. T _D = 50 K

23. M( dust ) = 7e8 M _sun M( H _2 ) = 2e10 M _sun M _dyn (r=2.5kpc) = 5e10 M _sun M _BH = 3e9 M _sun => 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? 1148+52: Masses

24. Cosmic (proper) time  T _univ = 0.87Gyr

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 03; Maiolino 04) ? => silicate grains? => Star formation started early (z > 10)?  Timescales

26. Cosmic Stromgren Sphere Accurate redshift from CO: z=6.419+/0.001 Ly a, high ioniz. Lines: uncertainty >1000km/s (  z=0.03) Proximity effect: photons leaking from 6.32<z<6.419 z=6.32 ‘time bounded’ Stromgren sphere: R = 4.7 Mpc t _qso = 1e5 R^3 f(HI)= 1e7yrs White et al. 2003

27. Richards et al. 2002 SDSS QSOs

28. Loeb & Rybicki 2000

29. 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 given fiducial lifetime, f _lt = 1e7 years?  Probability arguments suggest: f(HI) > 0.1 at z=6.4 – much better limit than GP Wyithe and Loeb 2003

30. z>6 QSOs with MgII and/or CO redshifts (Walter et al, Willot et al., Maiolino et al., Iwamuro et al.) = 0.08 => = 4.4 Mpc

31. Near-edge of reionization: GP + Cosmic Stromgren Spheres Very Fast? f(HI) > 1e-1 at z >= 6.4 (0.87Gyr) f(HI) < 1e-4 at z <= 5.7 (1.0 Gyr) See also Cosmic Stromgren Surfaces (Mesinger & Haiman 2004)

32. Gas and dust during the EoR FIR luminous galaxy at z=6.42: 1e13 L sun observe dust, gas, star formation, AGN Merging(?) galaxy: Molecular gas mass = 2x10 10 M _sun, M _dyn = 6e10 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?

33. J1048+4637: A second FIR-luminous QSO source at z=6.2 S _250 = 3.0 +/- 0.4 mJy => L _FIR = 7.5e12 L _sun z(MgII)  S(CO 3-2) = 0.17 +/- 0.09 mJy  EVLA correlator: 8GHz, 16000 channels z(opt) MAMBO 250 GHzVLA CO 3-2

34. VLA detections of HCN 1-0 emission n(H _2 ) > 1e5 cm^-3 (vs. CO: n(H _2 ) > 1e3 cm^-3) z=2.58 Solomon et al index=1 z=4.7 z=6.4 70 uJy

35. PKS 2322+1944 z=4.12: [CI] (492 GHz rest freq; Pety et al.) => Solar Metalicity PdBI VLA CO2-1

36. Continuum sensitivity of future arrays: Arp 220 vs z (FIR = 1.6e12 L _sun ) cm: Star formation, AGN (sub)mm Dust, molecular gas Near-IR: Stars, ionized gas, AGN

37. Redshifts for obscured/faint sources: wide band (16 - 32 GHz) spectrometers on LMT, GBT (Min Yun 04, Harris 04) L _FIR = 1e13 L _sun

38. Studying the pristine IGM beyond the EOR: redshifted HI 21cm observations (100 – 200 MHz) with the Square Kilometer Array. ‘Pathfinders’: LOFAR, MWA, PAST, VLA-VHF,… SKA goal:  Jy at 200 MHz Large scale structure: density, f(HI), T _spin

39. Low frequency background – hot, confused sky Eberg 408 MHz Image (Haslam + 1982) Coldest regions: T = 100  z)^2.6 K Highly ‘confused’: 3 sources/arcmin^2 with S _0.2 > 0.1 mJy

40. Terrestrial interference 100 MHz z=13 200 MHz z=6

41. Global reionization signature in low frequency HI spectra (Gnedin & Shaver 2003) double fast 21cm ‘deviations’ at 1e-4 wrt foreground Spectral index deviations of 0.001

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

43. Power spectrum analysis Zaldarriaga + 2003 LOFAR SKA Z=10 129 MHz 2deg 1arcmin

44. 1422+23 z=3.62 Womble et al. 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)

45. Cosmic web before reionization: HI 21cm Forest ( Carilli, Gnedin, Owen 2002) 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) (Furlanetto & Loeb 2003) Primordial disks: low cosmic density=0.001/unit z, but high opacity=> fainter radio sources -- GRBs? 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 (Carlli,Jarvis,Haiman) Z=10 20mJy Z=8

46. GMRT 228 MHz search for HI21cm abs toward highest z radio galaxy, 0924-220 z=5.2 Continuum point source = 0.55 Jy; rms/(40km/s chan) = 5 mJy z(CO) 230Mhz 8GHz 1” Van Breugel et al.

47. ‘EoR Pathfinders’: PAST, LOFAR, MWA, VLA-VHF, … MWA prototype (MIT/ANU) LOFAR (NL) PAST (CMU/China)VLA-VHF (CfA/NRAO)

48. VLA-VHF: 180 – 200 MHz Prime focus X-dipole (CfA/NRAO – Greenhill et al) Leverage: existing telescopes, IF, correlator, operations First light: Q4, 2005

49. Main Experiment: Cosmic Stromgren spheres around z>6 SDSS QSOs (Wyithe & Loeb 2004) VLA spectral/spatial resolution well matched to expected signal: 5’, 1000 km/s VLA-VHF 190MHz 250hrs 15’ 20mK 0.50+/-0.12 mJy

50. 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, ALMA 10-100x sensitivity is critical to study normal galaxies Low freq pathfinders: HI 21cm signatures of neutral IGM SKA imaging of IGM z 

51. Other Experiments: power spectrum analysis, ‘HI 21cm forest’  Sensitivity per 0.8MHz channel: currently have 16 channels over 12.5 MHz  Piggy-back on CSS experiment  Centrally condensed uv coverage

52. Challenges and ‘mitigation’: VLA-VHF CSS  Ionospheric phase errors – higher freq (freq^-2); 4deg FoV; 1km B _max  T _bg – higher freq (freq^-2.75)  Confusion (in-beam) – spectral measurement (eg. Morales & Hewitt 2004); mJy point source removal w. A array; precise position and redshift  Wide field problems – polarization, sidelobes, bandpass – all chromatic ?  RFI – “interferometric excision” (but D array); consistently ‘clean’ times in monitor plots (but very insensitive measure) ? Proposed Cost and Timeline  100K in parts (CfA) + labor (CfA/NRAO)  First tests (4 prototypes): Q1, Q2 2005  First experiments (100-200 hr): D array, Q4 2005  Large proposal (500 hr): D array, Q1 2007

53. System/Site characteristics Work hours TV carrier Proposed band First sidelobe = 15db

54. Ionospheric phase errors: VLA 74MHz (Lane etal.)  TIDs – ‘fuzz-out’ sources  ‘Isoplanatic patch’ = few deg = few km  Phase variation proportional to wavelength^2

55. 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: Australia, 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$ (20% for low freq only)

56. Weak correlation of L _FIR – M _B? M_B > -26: 10% detected at 250 GHz mJy sensitivity M_B < -26: 30% detected

57. Thermal State of IGM at high z: Ly a Forest (Hui and Haiman 2003)

58. White etal (2002): ‘superluminal’ ionization front  Stromgren sphere expands at close to speed of light => obs Ly  photons emitted just after ionizing photons  “Delay required to allow light to travel from source to the edge of the sphere is exactly compensated by the ‘speedup’ that results from that edge being closer to the observer”  “Expansion law for the observed radius is exactly the same as the expansion law derived ignoring light-travel effects”

59. Confusion by free-free emission during EOR (Oh & Mack 2003)

60. Difficulty with (LSS) emission observations: confusion by foreground radio sources (di Matteo 2001)

61. Beating confusion: exploiting the spectral domain (Morales & Hewitt 2004) Foreground: smooth continuum => cylindrical symmetry in Fourier space EoR HI: noise signal in frequency => spherical symmetry in Fourier space

62. 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

63. Gravitational Lensing?  CO 3-2 double source, 0.3” separation => strong lensing?  Keck near IR imaging: point source < 0.3” at K (Djorgovski)  HST/ACS imaging: point source < 0.1” (White et al. 2004 (?))  Radio continuum: foreground radio sources, but no SDSS cluster z< 0.1  QSO spectrum => “proto-cluster” at z=5 (White et al. 2002)? 1148+5251

64. Cosmic Stromgren Sphere Accurate redshift from CO: z=6.419+/0.001 Ly a, high ioniz. lines uncertainty >1000 km/s (  z=0.03) Proximity effect: photons leaking from 6.32<z<6.419 z=6.32 ‘time bounded’ Stromgren sphere: R = 4.7 Mpc t _qso = 1e5 R^3 f(HI) = 1e7yrs White et al. 2003

65. ALMA/EVLA/GBT redshift coverage for CO VLA CO(3-2), PdBI CO 6-5, 7-6 in J1148+5251 @ z=6.42 Epoch of Reionization

66. 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

67. 1148+5251: Starburst + QSO at z=6.42?  Starburst (double?) nucleus: size = few kpc around QSO  Star formation rate => stellar spheroid formation in 5e7 yrs?  SMBH formation: 1/e = few x10^7 yr (Loeb, Wyithe,…) => Coeval formation of galaxy/SMBH at z>6?

68. Temperatures: Spin, CMB, Kinetic and the 21cm signal Initially T _S = T _CMB T _S couples to T _K via Lya scattering T _K = 0.026 (1+z)^2 (wo. heating) T _CMB = 2.73 (1+z) T _S = T _CMB => no signal T _S = T _K Absorption against CMB T _S > T _CMB => Emission T _K T _CMB T _s Tozzi + 2002 z = 11z = 7  t = 10mK

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

71. Structure formation: the Dark Matter perspective = Press-Schechter Formalism z M_ 2  T _vir M_sun K 0 1e14 3e7 5 3e10 3e5 10 6e7 8e3

72. GMRT 230 MHz 0924-220 z=5.2 channel 20 (229.60MHz)

73. Cosmic Stromgren Surfaces: damping wing of Ly a line at sharp edge of sphere leads to apparently smaller sphere size (Mesinger & Haiman 2004)

74.  Dark matter: Analytic – “Press-Schechter Formalism” (Barkana & Loeb 2000 Rev Mod Phys)  IGM/galaxy formation: Numerical simulations

75. Minihalos: M _’Jeans’ = 1e4 M _sun (z=20) H _2 cooling: 1e5 – 1e7 M _sun =>T _vir = 300 to 1e3 K H _2 formation: Near UV dissociates, but soft Xray catalyze? Form 100 M _sun stars (popIII)? Totally disrupted by single SNe => self-distruct in 1e6 years Protogalaxies : H line cooling => T _vir > 1e4 K Structure formation: the Baryons

76. SDSS + DPOSS: 700 at z > 4 30 at z > 5 9 at z > 6 M _B L _bol > 1e14 L _sun M _BH > 1e9 M _sun Fan et al 2000 High redshift QSOs Luminous “SDSS” QSOs: insufficient to reionization the universe

77. 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 => 4  ALMA detection in 1 minute!  Expect 1 – 2 “normal” galaxies ALMA FoV at z>6 per in 10hrs

78. z=6.56  1 arcmin^2 (H _AB = 27)  0.3 L*(z=3)  SFR = few M _sun /year Ly alpha emitting galaxies within EoR: near-IR observations (Hu, Taniguchi, Stanway, Bouwens, Yan, Dickinson…)