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ALMA studies of the first galaxies Madrid 2006 Chris Carilli (NRAO) Epoch of Reionization •last phase of cosmic evolution to be explored •bench-mark in cosmic structure formation indicating the first luminous structures First observational constraints on cosmic reionization Gunn-Peterson Effect (Fan) z=5.80 z=5.82 => Near edge of reionization at z ~ 6. z=5.99 z=6.28 T Current observations: z_reion = 11 to 6 (Fan, Carilli, Keating 2006) Not ‘event’, but complex process, large variance time/space GP => occurs in ‘twilight zone’, opaque _obs < 0.9 um Radio astronomical probes of the Epoch of Reionization and the 1st luminous objects CMB large scale polarization Neutral IGM – HI 21cm emission and absorption Objects within EoR – Molecular gas, dust, star formation Collaborators USA – Carilli, Wang, Fan, Strauss Euro – Bertoldi, Walter, Riechers, Cox, Menten, Omont, Beelen Dust at z ~ 6 (see Bertoldi) • 30% of z=6 QSO host galaxies = Hyper-lum. IR galaxies: LFIR ~ 1e13 Lo • Mdust ~ 1e8 Mo • tuniv < 1Gyr => Dust formation in massive stars? S250 = 3mJy Near-IR to Radio SEDs: Star formation? • Hot (1000K) dust = AGN accretion disk • Warm (50K) dust = starburst? • Follow radio-FIR correlation • SFR(>5Mo) ~ 1e3 Mo/yr Similarity to IR-selected QSOs, not optical (PG) QSOs: • Coeval formation of SMBH + stellar host galaxy? • Consistent with ‘downsizing’ in galaxy/SMBH formation. Molecular gas + fine structure lines (Walter) z=6.42; t_univ=0.87 Gyr J1148 VLA: CO 3-2 [CII] IRAM 2.5” CO 6-5 1148+5251 Only direct probe of host galaxy 0.3” [CII] luminosity also implies SFR ~ 1e3 Mo/yr (Maiolino) 2e10 Mo of molecular gas = fuel for star formation Early enrichment of heavy elements: zsf > 8 Tb = 40K Breakdown MBH - Mbulge relation at high z: SMBH forms first? CO => Mgas = 2e10 Mo 1148+5251 X Mdyn = 5e10 Optical => MBH = 2e9 => Mbulge = 1e12 MBULGE ~ 1000MBH Cosmic Stromgren Spheres • 1148+5251: Accurate z_host from CO: z=6.419+/0.001 • Proximity effect: photons leaking from 6.32<z<6.419 White et al. 2003 •‘time bounded’ Stromgren sphere: R = 4.7 Mpc • f(HI) = 1e-5 R^-3 (t_qso/1e7) yrs • <f(HI)> ~ 0.1 for sample 19 QSOs at z>5.7 (Fan et al. 06; Wyithe et al. 04) Current limits: z=5.7 Ly galaxies in COSMOS (Murayama/Scoville) NB850 99 Ly emitters at z=5.7+/-0.05 SUBARU: Ly = 2 Mo/yr MAMBO: <S250> <2mJy => SFR<300 VLA: <S1.4> <2.5Jy => SFR<125 VLA Complementary: Panchromatic view of galaxy formation SFR=10M_sun/yr cm: Star formation, AGN (sub)mm: Dust Near-IR: Stars, Ionized gas, AGN Line sensitivity High order, fine structure lines Low order Wootten CO HCO+ HCN CCH z=6.55 Detect dust emission in 1sec (5) at 250 GHz SFR>10M_sun/yr Detect multiple lines, molecules per band => detailed astrochemistry Image dust and gas at sub-kpc resolution => gas dynamics/dark matter ALMA – Probing Cosmic Reionization ‘Twilight zone’: z=6-11 limited to near-IR to radio First forays: z=6 QSOs Host • HLIRGs: early dust/C,O.. formation • Coeval formation SMBH+Host Gal. • Break-down MBH-Mbulge • CSS => f(HI) > 0.1 ALMA: dust, gas, dark matter • Imaging of ‘normal galaxies’ •Detailed physics and astrochemistry Loeb & Rybicki 2000 First observational constraints on cosmic reionization Gunn-Peterson Effect Large scale polarization of CMB z=5.80 TT TE z=5.82 EE T z=5.99 Page z=6.28 Fan 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.