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The other side of galaxy formation: radio line and continuum ‘Great Surveys’ Santa Fe November 2008 Chris Carilli NRAO. ESO. Cosmological deep fields: COSMOS Definitive study of galaxy and SMBG evolution vs. environmnent ACS: 600 orbits for 2deg 2 to I AB = 26

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  1. The other side of galaxy formation: radio line and continuum ‘Great Surveys’ Santa Fe November 2008 Chris Carilli NRAO ESO

  2. Cosmological deep fields: COSMOS • Definitive study of galaxy and SMBG evolution vs. environmnent • ACS: 600 orbits for 2deg2 to IAB = 26 • VLA, Spitzer, 11-band SUBARU++, Galex, Chandra/XMM • Similar to SDSS in volume and resolution but at z > 1 • 2e6 galaxies from z~ 0 to 7

  3. Star formation rate density vs. redshift ‘epoch of galaxy assembly’

  4. Next level of detail: galaxy formation as function of M* ‘specific star formation rates’ = SFR/M* ‘active star formation’ tH-1 ‘red and dead’ ‘Downsizing’ Zheng+

  5. UV correction factor ~ 5x Star formation history of Universe: dirty little secret • Optical limitations • Dust obscuration: missing earliest, most active phases of galaxy formation • Only stars and star formation: not (cold) gas => missing the other half of the problem = ‘fuel for galaxy formation’

  6. Wilson et al. Radio astronomy: unveiling the cold, obscured universe • mm continuum: thermal emission from warm dust = star formation (see Yun) • (sub)mm lines: molecular gas, fine structure ISM cooling lines • (short) cm lines: low order molecular transitions, dynamics • cm continuum: synchrotron emission = star formation • (long) cm lines: HI 21cm (see Henning) HST / OVRO CO 850um Class 0 protostar

  7. COSMOS VLA deep 16x • Full field at 1.4GHz • 1.5” resolution • rms ~ 8 uJy/beam • 4000 sources (10xHUDF) (mostly) star forming galaxies

  8. Radio Surveys - Limits 14 AGN or 13 Submm gals: SFR > 103 Mo yr-1 12 Log (FIR Luminosity) ULIRGs~Arp220 SFR ~ 100 Mo/yr 40uJy 11 LIRGs~ M82 SFR~ 10 Mo/yr 10 Milky Way SFR ~ 1 Mo/yr 9

  9. BzK at z=1.7 4000A Ly-break Pushing uJy radio studies to z>2: Stacking Cosmos BzK, LBG and LAE Median stacking of high-z ‘dropout’ samples in Cosmos field • 30,000 BzK at z~1.3 to 2.5 • 8500 LBGs (U,B,V dropouts) at z~ 3, 4, 5 • 100 LAE in NB850 at z = 5.7 • ‘normal’ star forming galaxy populations at high redshift • Stacking analysis: ~ sub-uJy limits

  10. 30,000 sBzK galaxies in Cosmos (>5x previous): Pannella+ HST Photo z z~1.3 to 2.5 star forming Daddi, McCracken + 3.2” • nearIR selected: KAB ~ 23 • M* ~ 1010 to 1011 Mo • HST sizes ~ 1” ~ 9kpc • Density ~ few x10-4 Mpc-3 ~ 30x SMG • Forming ‘normal’ ellipticals, large spirals?

  11. VLA stack 30,000 sBzK Pannella + <S1.4> = 8.8 +/- 0.1 uJy => <SFR> ~ 96 Mo yr-1 < 0.1x SMG Size ~ 1” 2e10 3e11 SKA (sub-uJy) science before the SKA

  12. Stacking in bins of 4000 1010 Mo 3x1011 Mo S1.4 increases with B-z => dust extinction increases with SFR (or M*) S1.4 increases with M* => SFR increases with stellar mass

  13. 1.4GHz SSFR z=2.1 z=1.5 5x tH-1 (z=1.8) z=0.3 UV SSFR Dawn of Downsizing: SFR/M* vs. M* • SSFR increases with z • SSFR constant with M*, unlike z<1=> ‘pre-downsizing’ • z>1.5 sBzK well above the ‘red and dead’ galaxy line • Extinction increases with SFR, M* • <factor 5> UV dust correction needs to be differential wrt SFR, M*

  14. Great Surveys: next gen radio deep fields Arcsec resolution is required to avoid confusion and detect ‘normal’ star forming galaxies at z > 1.5 All confusion limited (res>5”)

  15. Early Universe Molecular Line Galaxies Most distant SMG COSMOS J1000+0234 z=4.52 Submm galaxies: z ~ 1.5 to 4.5 QSO host galaxies: z ~ 1 to 6.4 SDSS J1335+3533 z=6.04 • Gas mass (H2)~ 1010 to 1011 Mo(~ 10 to 100x MW) • FIR > 1013 Lo => Star formation rates > 103 Mo yr-1 • Giant elliptical galaxy formation at high redshift?

  16. Gas, Dust, Star Form, in host galaxy of J1148+5251 z=6.42 1” • SMBH ~ 1e9 Mo • Dust mass ~ 7e8 Mo • Gas mass ~ 2e10 Mo • CO size ~ 6 kpc • Dynamical Mass ~ 4e10 Mo Only direct observations of host galaxy properties

  17. Continuum SED and CO excitation: ISM physics at z=6.42 Elvis QSO SED 50K NGC253 Radio-FIR correlation MW • FIR excess -- SED consistent with starburst: SFR ~ 3000 Mo/yr • CO excitation ~ starburst nucleus: Tkin ~ 100K, nH2~ 1e5 cm-3

  18. Building giant elliptical galaxies + SMBHs at tuniv < 1Gyr z=6 QSO host stats (33 total) z=10 10.5 Li, Hernquist, Roberston.. 8.1 • 10 in dust: FIR > 1e13 Lo • 5 in CO: Mgas > 1e10 Mo • 10 at 1.4 GHz continuum • 2 in [CII] • => SFR > 103 Mo yr-1 6.5 • Rapid enrichment of metals, dust, molecules • Rare, extreme mass objects: ~ 100 SDSS z~6 QSOs on entire sky

  19. LFIR vs L’(CO) ~ SFR vs. total gas mass Integrated Schmidt-Kennicutt Law • Star formation efficiency = SFR per unit gas mass, increases with increasing SFR • Gas depletion timescale = Mgas/SFR decreases with SFR 1e3 Mo/yr SFR High z tdep~1e7 yr Low z tdep~3e8 yr High-z sources = 10 -- 100 x Mgas of Milky Way Current sens ~ few x1010 Mo Index=1.5 Gas Mass

  20. sBzK: not extreme starbursts, but massive gas reservoirs Daddi + 2008 • 6 of 6 sBzK detected in CO with Bure • Gas mass > 1010 Mo ~ submm galaxies, but • SFR < 10% submm gal • 5 arcmin-2 (~50x submm galaxies)

  21. Starburst Daddi + Dannerbauer + FIR/L’CO = spiral (not starburst) Excitation = Milky Way (not starburst) • Extreme gas rich galaxies without extreme starbursts • Gas depletion timescales > 5 x108 yrs

  22. Mgas >~ M* sBzK ?? Current limitation: CO search requires optical pre-selection Low z ellipt

  23. Great Surveys: blind molecular line ‘piggy back’ surveys using 8GHz bandwidth • EVLA: CO 1-0 at z = 1.4 to 1.9 (48 to 40 GHz) • FoV ~ 1 arcmin2 => ~ 2 or 3 sBzK (M* > 1010 Mo) • rms (10hr, 300 km/s) = 50 uJy => L’(CO) = 1.9e9 K km/s pc2 • 4 mass limit: M(H2) = 3x1010 Mo (Galactic X factor) • => Every ‘Q-band’ full synthesis will have ~ 1 sBzK CO detection • ALMA: CO 2-1 at z = 1.45 to 1.7 (93 to 85 GHz) • FoV ~ 1 arcmin2 , but fractional BW (z) ~ 1/2 EVLA • S2-1 ~ 4xS1-0 (in Jy) and rms (300 km/s) ~ 30uJy • Mass limit ~ 5x109 Mo • => Every ‘Band 3’ full synthesis will have ~ 3 sBzK CO detections

  24. What is EVLA? First steps to the SKA By building on the existing infrastructure, multiply ten-fold the VLA’s observational capabilities, including 10x continuum sensitivity (1uJy), full frequency coverage (1 to 50 GHz), 80x BW (8GHz) • Antenna retrofits now 50% completed. • Early science Q1 2010, using new correlator. • Full receiver complement completed 2012.

  25. What is ALMA? International collaboration to build & operate largest millimeter/submm array at 5000m in northern Chile -> order of magnitude, or more, improvement in all areas of (sub)mm astronomy, including resolution, sensitivity, and frequency coverage. AOS Technical Building Array operations center Antenna commissioning in progress • Antennas, receivers, correlator in production: best (sub)mm receivers and antennas ever! • Site construction well under way: Observation Support Facility, Array Operations Site, antenna pads • North American ALMA Science Center (C’Ville): support early science Q4 2010, full ops Q4 2012

  26. END ESO

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