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Radio observations of dust and cool gas in the first galaxies Chris Carilli (NRAO) RAS March 2012. Current State-of-Art: host galaxies of z ~ 6 quasars and the early formation of massive galaxies and SMBH The Future is now! The Atacama Large Millimeter Array and Jansky Very Large Array

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  1. Radio observations of dust and cool gas in the first galaxies Chris Carilli (NRAO) RAS March 2012 • Current State-of-Art: host galaxies of z ~ 6 quasars and the early formation of massive galaxies and SMBH • The Future is now! The Atacama Large Millimeter Array and Jansky Very Large Array • Thanks: Wang, Riechers, Walter, Fan, Bertoldi, Menten, Cox ESO

  2. cm to submm diagnostics of galaxy formation 100 Mo yr-1 at z=5 • Low J CO emission: total gas mass, dynamics • High density gas tracers (HCN, HCO+) • Synch. + Free-Free = star formation EVLA and GBT Line • High J molecular lines: gas excitation, physical conditions • Dust continuum = star formation • Atomic fine structure lines: ISM gas coolant

  3. SDSS Apache Point NM Massive galaxy and SMBH formation at z~6: Quasar host galaxies at tuniv<1Gyr • Why quasars? • Rapidly increasing samples: z>4: > 1000 known z>5: > 100 z>6: > 20 • Spectroscopic redshifts • Extreme (massive) systems: Lbol ~1014 Lo=> MBH~ 109 Mo => Mbulge~ 1012 Mo 1148+5251 z=6.42

  4. 0.9um Gunn-Peterson effect toward z~6 SDSS QSOs • Pushing into the tail-end of cosmic reionization => sets benchmark for first luminous structure formation • GP effect => study of ‘first light’ is restricted to obs> 1um Fan 05

  5. Dust in high z quasar host galaxies: 250 GHz surveys HyLIRG Wang sample 33 z>5.7 quasars • 30% of z>2 quasars have S250 > 2mJy • LFIR ~ 0.3 to 1.3 x1013 Lo • Mdust ~ 1.5 to 5.5 x108Mo (κ125um = 19 cm2 g-1)

  6. Dust formation at tuniv<1Gyr? • AGB Winds > 109yr • High mass star formation? (Anderson, Dwek, Cherchneff, Shull, Nozawa) • ‘Smoking quasars’: dust formed in BLR winds/shocks (Elvis, Ilitzur) • ISM dust formation (Draine) • Extinction toward z=6.2 QSO + z~6 GRBs => different mean grain properties at z>4 (Perley, Stratta) • Larger, silicate + amorphous carbon dust grains formed in core collapse SNe vs. eg. graphite SMC, z<4 quasars Galactic z~6 quasar, GRBs Stratta et al.

  7. Under standard model assumptions (Michalowski ea 2011): • AGB stars: insufficient in most instances • SN: sufficient only if no dust destruction

  8. Dust heating? Radio to near-IR SED Star formation low z QSO SED TD ~ 1000K Radio-FIR correlation • FIR excess = 47K dust • SED = star forming galaxy with SFR ~ 400 to 2000 Mo yr-1

  9. Fuel for star formation? Molecular gas: 8 CO detections at z ~ 6 with PdBI, VLA • M(H2)~ 0.7 to 3 x1010 (α/0.8) Mo • Δv = 200 to 800 km/s • Accurate host galaxy redshifts 1mJy

  10. CO excitation: Dense, warm gas, thermally excited to 6-5 230GHz 691GHz starburst nucleus Milky Way • Radiative transfer model => Tk > 50K, nH2 = 2x104 cm-3 • Galactic Molecular Clouds (50pc): nH2~ 102 to 103 cm-3 • GMC star forming cores (~1pc): nH2~ 104 cm-3 • => Entire ISM (kpc-scales) ~ GMC SF cloud core!

  11. LFIR vs L’(CO): ‘integrated K-S Star Formation relation’ • Further circumstantial evidence for star formation • Gas consumption time (Mgas/SFR) decreases with SFR FIR ~ 1010 Lo/yr => tc > 108yr FIR ~ 1013 Lo/yr => tc < 107yr SFR 1e3 Mo/yr Index=1.5 MW 1e11 Mo Mgas

  12. Imaging => dynamics => weighing the first galaxies z=6.42 0.15” TB ~ 25K PdBI CO7-6 CO3-2 VLA -150 km/s 7kpc 1” ~ 5.5kpc + +150 km/s • Size ~ 6 kpc, with two peaks ~ 2kpc separation • Dynamical mass (r < 3kpc) ~ 6 x1010 Mo • M(H2)/Mdyn ~ 0.3

  13. Break-down of MBH – Mbulge relation at high z • <MBH/Mbulge> ~ 15 higher at z>4 => Black holes form first? • Caveats: • Better CO imaging (size, i) • Bias for optically selected quasars? • At high z, CO only method to derive Mbulge

  14. [CII] 1” [NII] [CII] 158um search in z > 6.2 quasars • Dominant ISM gas cooling line, tracing CNM and PDRs • [CII] strongest cm to FIR line in SF galaxies ~ 0.1% to 1% LGal • z>4 => FS lines observed in (sub)mm bands; z>6 => Bure! • S[CII] = 3mJy • S250GHz < 1mJy • L[CII] = 4x109 Lo • S250GHz = 5.5mJy • S[CII] = 12mJy

  15. 1148+5251 z=6.42:‘Maximal star forming disk’ PdBI 250GHz 0.25”res • [CII] size ~ 1.5 kpc => SFR/area ~ 1000 Mo yr-1 kpc-2 • Maximal starburst (Thompson, Quataert, Murray 2005) • Self-gravitating gas and dust disk • Vertical disk support by radiation pressure on dust grains • ‘Eddington limited’ SFR/area ~ 1000 Mo yr-1 kpc-2 • eg. Arp 220 on 100pc scale, Orion SF cloud cores < 1pc

  16. [CII] SMC • CII/FIR: Large scatter, with possible cut-off at FIR ~ 1012 Lo • lower gas heating efficiency due to charged dust grains in high radiation environments (Malhotra) • Opacity in FIR may also play role (Papadopoulos) • Low metalicity => high CII/FIR: increased UVMFP (Israel ea 2011)

  17. [CII] SF gal AGN Stacey ea 2011 • High z sources: even larger scatter • SF galaxies: CII/FIR ~ 0.1% to 1% • AGN: CII/FIR < 0.1%

  18. Summary: cm/mm observations of 33 quasars at z~6 Only direct probe of the host galaxies JVLA 160uJy J1425+3254 CO at z = 5.9 • 11 in mm continuum => Mdust ~ 108 Mo: Dust formation? • 10 at 1.4 GHz continuum: Radio to FIR SED => SFR ~ 1000 Mo/yr • 8 in CO => Mgas ~ 1010 (α/0.8) Mo = Fuel for star formation • High excitation ~ starburst nuclei, but on kpc-scales • Follow star formation law: tc ~ 107 yr • Departure from MBH – Mbulge at z~6: BH form first? • 3 in [CII] => maximal star forming disk: 1000 Mo yr-1 kpc-2

  19. Building a giant elliptical galaxy + SMBH at tuniv< 1Gyr • ‘Massive-Black’ hydro-simulation ~ 1cGpc3 (di Matteo ea. 2012) • Stellar mass > 1011 Mo forms via efficient cold mode accretion: SFR ~ gas accretion rate > 100 Mo yr-1 • SMBH of ~ 109 Mo forms (first) via steady, Eddington-limited accretion • Evolves into giant elliptical galaxy in massive cluster (1015 Mo) by z=0

  20. Building a giant elliptical galaxy + SMBH at tuniv< 1Gyr • Good news: Rapid enrichment of metals, dust in early, massive galaxies • Bad news: Rare, extreme mass objects: ~ 100 SDSS z~6 QSOs on entire sky! • Goal: push to first ‘normal’ galaxies

  21. Karl G. Jansky Very Large Array • 80x Bandwidth (8 GHz, full stokes), with 4000 channels • 5x frequency coverage (continuous 1 to 50 GHz) • 10x continuum sensitivity (<1uJy) • Spatial resolution ~ 40mas at 43 GHz

  22. Atacama Large Milllimeter Array • High sensitivity array = 54x12m • Wide field imaging array = 12x7m • Frequencies = 80 GHz to 900 GHz • Resolution = 20mas at 800 GHz • Sensitivity = 13uJy in 1hr at 230GHz ALMA+EVLA represent an order of magnitude, or more, improvement in observational capabilities from 1 GHz to 1 THz!

  23. ALMA and first galaxies 100Mo/yr 10Mo/yr ALMA small FoV (1’ at 90GHz) => still need wide field cameras on large single dishes

  24. 8GHz spectroscopy SMG at z~6 in 24hrs • ALMA: Detect multiple lines, molecules per 8GHz band = real spectroscopy/astrochemistry • EVLA: 30% FBW, ie.19 to 27 GHz (CO1-0 at z=3.2 to 5.0) => large cosmic volume searches for molecular gas w/o need for optical redshifts

  25. First JVLA results: 46GHz, BW=256MHz, FoV = 1’ CO1-0 sBzK z=1.5 • CO 2-1 from 3 SMGs z~4.0 • CO 1-0 from normal SF galaxy z ~ 1.5 • => Every few hour observation with JVLA at > 20 GHz will discover new galaxies in CO! HST/SUBMM z=4.055 4.056 4.051 CO2-1

  26. On time and on budget • Early science ApJ special issue: September 2011

  27. ALMA status (Jan 2012) • 27 Antennas on high-site • 54 antennas in Chile • 38 front-ends delivered • Early science has begun (8/1 over subscription!) • Full operation by end 2013

  28. The VLA Strikes Back!

  29. Y J H ≤ z Bouwens ea 2012 • z > 7 Ly-break galaxies • SFR ~ 1 to 10 Mo yr-1 • > 1 arcmin-2 • Decreasing dust content w. z X1600A

  30. Comparison to low z quasar hosts z=6 FIR lum quasars IRAS selected z=6 stacked mm non-detections PG quasars

  31. EVLA/ALMA Deep fields: 1000hrs, 50 arcmin2, 8GHz BW • Volume (EVLA, z=2 to 2.8) = 1.4e5 cMpc3 • 1000 galaxies z=0.2 to 6.7 in CO with M(H2) > 1010 (α/3.8) Mo • 100 in [CII] z ~ 6.5 • 5000 in dust continuum New horizon for deep fields! Millennium Simulations Obreschkow & Rawlings

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