ESO ALMA, EVLA, and the Origin of Galaxies (Dense Gas History of the Universe) Chris Carilli (NRAO) Bonn, Germany, September 2010 The power of radio astronomy: dust, cool gas, and star formation Current State-of-Art  z ~ 6: Quasar host galaxies = early formation of massive galaxies and SMBH  z ~ 1 to 3: Normal galaxy formation during the epoch of galaxy assembly = probing the ‘Gas Rich Universe’ Bright (near!) future: The Atacama Large Millimeter Array (and CCAT!) and Expanded Very Large Array – recent example! Thanks: Wang, Riechers, Walter, Fan, Bertoldi, Menten, Cox, Daddi, Schinnerer, Pannella, Aravena, Smolcic, Neri, Dannerbauer…

Star formation history of the Universe (mostly optical view) ‘epoch of galaxy assembly’ ~50% of present day stellar mass produced between z~1 to 3 Bouwens + First light + cosmic reionization

Star formation as function of stellar mass t H -1 ‘active star formation’ ‘red and dead’ Zheng ea ‘Downsizing’: Massive galaxies form most of stars quickly, at high z (see also: stellar pop. synthesis at low z; evolved galaxies at z ~1 to 2) specific SFR = SFR/M * ~ e-folding time -1

Optical Limitation 1: Dust Bouwens +

Optical Limitation 2: Cold gas = fuel for star formation (‘The missing half of galaxy formation’) Low z spirals Integrated Kennicutt- Schmidt star formation law: relate SFR and gas content of galaxies Power-law index = 1.5 ‘SFR’ ‘M gas ’

Millimeter through centimeter astronomy: unveiling the cold, obscured universe cm/mm reveal the dust-obscured, earliest, most active phases of star formation in galaxies cm/mm reveal the cool gas that fuels star formation HST/CO/SUBMM COCO Wilson et al. CO image of ‘Antennae’ merging galaxies GN20 z=4 submm galaxy

Radio – FIR: obscuration-free estimate of massive star formation  Radio: SFR = 1x L 1.4 W/Hz  FIR: SFR = 3x L FIR (L o )

Spectral lines Molecular rotational lines Atomic fine structure lines z=0.2 z=4 cm submm Molecular gas CO = total gas mass tracer  M(H 2 ) = α L’(CO(1-0)) Velocities => dyn. mass Gas excitation => ISM physics (densities, temperatures) Astrochemistry/biology, eg. dense gas tracers (HCN) directly associated with star formation (Smail, van Dishoeck) Gas supply: smooth accretion or major gas rich mergers?

Fine Structure lines [CII] 158um ( 2 P 3/2 - 2 P 1/2 )  Principal ISM gas coolant: photo-electric heating by dust  Traces star forming regions and the CNM  [CII] most luminous line from meter to FIR, up to 1% L gal  Herschel: revolutionary look at FSL in nearby Universe – AGN/star formation diagnostics (Hailey-Dunsheath) [CII] CO [OI] 63um [CII] [OIII] 88um [CII] [OIII]/[CII] Cormier et al. Fixsen et al.

Plateau de Bure Interferometer High res imaging at 90 to 230 GHz rms < 0.1mJy, res < 0.5” MAMBO at 30m (Cox) 30’ field at 250 GHz rms < 0.3 mJy Very Large Array 30’ field at 1.4 GHz rms< 10uJy, 1” res High res imaging at 20 to 50 GHz rms < 0.1 mJy, res < 0.2” Powerful suite of existing cm/mm facilites First glimpses into early galaxy formation

Theme I: Massive galaxy and SMBH formation at z~6 – Quasar hosts at t univ <1Gyr Why quasars?  Rapidly increasing samples: z>4: > 1000 known z>5: > 100 z>6: 20  Spectroscopic redshifts  Extreme (massive) systems: L bol ~10 14 L o => M BH ~ 10 9 M o => M bulge ~ M o  Downsizing: study of very early massive galaxy formation intrinsically interesting z=6.42 SDSS Apache Point NM

LFIR ~ 0.3 to 1.3 x10 13 L o (~ 1000xMilky Way) M dust ~ 1.5 to 5.5 x10 8 M o Dust formation at t univ <1Gyr? AGB Winds ≥ 1.4e9yr  High mass star formation? (Dwek, Anderson, Cherchneff, Shull, Nozawa, Valiante) HyLIRG Dust in high z quasar host galaxies 30% of z>2 quasars have S 250 > 2mJy Wang sample 33 z>5.7 quasars MAMBO 30m 250GHz surveys

Dust heating? Radio to near-IR SED T D = 47 K  FIR excess = 47K dust  SED consistent with star forming galaxy: SFR ~ 400 to 2000 M o yr -1 Radio-FIR correlation low z SED T D ~ 1000K Star formation? AGN

Fuel for star formation? Molecular gas: 8 CO detections at z ~ 6 with PdBI, VLA M(H 2 ) ~ 0.7 to 3 x10 10 (α/0.8) M o Δv = 200 to 800 km/s Accurate host galaxy redshifts 1mJy

CO excitation: Dense, warm gas, thermally excited to 6-5 LVG model => T k > 50K, n H2 = 2x10 4 cm -3 Galactic Molecular Clouds (50pc): n H2 ~ 10 2 to 10 3 cm -3 GMC star forming cores (≤1pc): n H2 ~ 10 4 cm -3 Milky Way starburst nucleus 230GHz691GHz (Papadopoulos, Smail)

L FIR vs L’(CO): Star Formation Law Index=1.5 1e11 M o 1e3 M o /yr Further circumstantial evidence for star formation Gas consumption time (M gas /SFR) decreases with SFR FIR ~ L o /yr => t c > 10 8 yr FIR ~ L o /yr => t c < 10 7 yr SFR M gas MW

 Size ~ 6 kpc, with two peaks ~ 2kpc separation  Dynamical mass (r < 3kpc) ~ 6 x10 10 M o  M(H 2 )/M dyn ~ 0.3 Imaging => dynamics => weighing the first galaxies z= km/s +150 km/s 7kpc 1” ~ 5.5kpc CO3-2 VLA ” T B ~ 25K PdBI

Break-down of M BH – M bulge relation at very high z z>4 QSO CO z<0.2 QSO CO Low z galaxies M BH ~ 0.002M bulge ~ 15 higher at z>4 => Black holes form first? (Maiolino) ‘Causal connection between galaxy and SMBH formation’ At high z, CO only method to derive M bulge

For z>6 => redshifts to 250GHz => Bure! (Knudsen) 1” [CII] [NII] Fine Structure Lines: [CII]158um search in z > 6.2 quasars L [CII] = 4x10 9 L o (L [NII] < 0.1L [CII] ) S 250GHz = 5.5mJy S [CII] = 12mJy S [CII] = 3mJy S 250GHz < 1mJy => don’t pre-select on dust

z=6.42:‘Maximal star forming disk’ [CII] size ~ 1.5 kpc => SFR/area ~ 1000 M o 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 M o yr -1 kpc -2  eg. Arp 220 on 100pc scale, Orion SF cloud cores < 1pc PdBI 250GHz 0.25”res

 11 in mm continuum => M dust ~ 10 8 M o : Dust formation in SNe?  10 at 1.4 GHz continuum: Radio to FIR SED => SFR ~ 1000 M o /yr  8 in CO => M gas ~ M o = Fuel for star formation in galaxies  High excitation ~ starburst nuclei, but on kpc-scales  Follow star formation law (L FIR vs L’ CO ): t c ~ 10 7 yr  Departure from M BH – M bulge at z~6: BH form first?  3 in [CII] => maximal star forming disk: 1000 M o yr -1 kpc -2 J CO at z = 5.9 Theme I summary: cm/mm observations of 33 quasars at z~6 – only direct probe of the host galaxies EVLA 160uJy

Building a giant elliptical galaxy + SMBH at t univ < 1Gyr (‘extreme downsizing’)  Multi-scale simulation isolating most massive halo in 3 Gpc 3  Stellar mass ~ 1e12 M o forms in series (7) of major, gas rich mergers from z~14, with SFR  1e3 M o /yr  SMBH of ~ 2e9 M o forms via Eddington-limited accretion + mergers  Evolves into giant elliptical galaxy in massive cluster (3e15 M o ) by z= Rapid enrichment of metals, dust in ISM Rare, extreme mass objects: ~ 100 SDSS z~6 QSOs on entire sky Goal: push to normal galaxies at high redshift Li, Hernquist et al. Li, Hernquist+

HST Theme II: ‘Normal’ star forming galaxies during epoch of galaxy assembly (‘sBzK’ at z ~ 2)  color-color diagrams identify thousands of z~ 2 star forming galaxies  near-IR selected => ‘stellar mass limited sample’: M * ~ to M o  Common ~ few x10 -4 Mpc -3 (5 arcmin -2 ) HST imaging => disk sizes ~ 1” ~ 8kpc, punctuated by massive star forming regions

 = 96 M o yr -1 [FIR ~ 3e11 L o ]  VLA size ~ 1” ~ HST Pannella + = 8.8 +/- 0.1 uJy Unbiased star formation rates in z~2 sBzK VLA 1.4GHz stacking: 30,000 in COSMOS COSMOS 2 deg 2 Deep Field (Scoville ea) Approaching SDSS volume at z > 1 2e6 galaxies from z~ 0 to 7 (Decarli)

 SFR ~ independent of blue magnitude  SFR increases with B-z => dust extinction increases with SFR (or M * )  SFR increases with stellar mass Stacking in bins of M o 3x10 11 M o

Dawn of Downsizing: SFR/M * vs. M * (Karim) 5x t H -1 (z=1.8) z= GHz SSFR z=1.5 z=2.1 UV SSFR  SSFR constant with M *, unlike z ‘pre-downsizing’ ~ constant efolding time  z>1.5 sBzK well above the ‘red and dead’ galaxy line => even large growing exponentially  UV dust correction = f(SFR, M * ) [factor 5 at 2e10 M o ~ LBG (Shapely+ 01)]

CO observations with Bure: Massive gas reservoirs without extreme starbursts (Daddi ea 2009)  6 of 6 sBzK detected in CO  Gas mass ~ M o ~ gas masses in high z HyLIRG but  SFR < 10% HyLIRG  Gas masses ≥ stellar masses => pushed back to epoch when galaxies are gas dominated!

 Lower CO excitation: low J observations are key!  FIR/L’CO: Gas consumption timescales >= few x10 8 yrs HyLIRG Closer to Milky Way-type gas conditions (Dannerbauer) 1 1.5

Summary Theme II: Probing the Gas Rich Universe = Gas dominated, normal galaxy formation at z ~2  SSFR constant with M * : ‘pre-downsizing’  Well above ‘red + dead’ curve up to M *  Gas masses ~ M o ≥ stellar masses  Gas consumption time > few x10 8 yrs ‘Secular (spiral) galaxy formation during epoch of galaxy assembly’ Great promise for ALMA + EVLA! Genzel + 08

What is the EVLA? similar ten- fold improvement in most areas of cm astronomy frequencies = 1 to 50 GHz 8 GHz BW => 80x old res = 40mas res at 43GHz rms = 6uJy in 1hr at 30GHz What is ALMA? Tenfold improvement (or more), in all areas of (sub)mm astronomy, including resolution, sensitivity, and frequency coverage. antennas: 54x12m, 12x7m antennas frequencies: 80 GHz to 720 GHz res = 20mas res at 700 GHz rms = 13uJy in 1hr at 230GHz ALMA+EVLA ~ Order magnitude improvement from 1GHz to 1 THz! (Testi)

(sub)mm: dust, high order molecular lines, fine structure lines -- ISM physics, dynamics cm telescopes: star formation, low order molecular transitions -- total gas mass, dense gas tracers 100 M o yr -1 at z=5 Pushing to normal galaxies EVLA 1.4 GHz continuum: thousands of sBzK galaxies

ALMA and first galaxies: [CII] 100M o /yr 10M o /yr ALMA ‘redshift machine’: [CII] in z>7 dropouts

Wide bandwidth spectroscopy ALMA: Detect multiple lines, molecules per 8GHz band = real astrochemistry EVLA 30 to 38 GHz (CO2-1 at z=5.0 to 6.7) => large cosmic volume searches for molecular gas (1 beam = 10 4 cMpc 3 ) w/o need for optical redshifts J at z=6.4 in 24hrs with ALMA

ALMA Status Antennas, receivers, correlator in production: best submm receivers and antennas ever! Site construction well under way: Observation Support Facility, Array Operations Site, 5 Antenna interferometry at high site! Early science call Q EVLA Status Antenna retrofits 70% complete (100% at ν ≥ 18GHz). Early science in March 2010 using new correlator (2GHz) Full receiver complement completed GHz 5 antennas on high site

GN20 molecule-rich proto-cluster at z=4 CO 2-1 in 3 submm galaxies, all in 256 MHz band z= mJy 1000 km/s 0.3mJy SFR ~ 10 3 M o /year M gas ~ M o Early, clustered massive galaxy formation +250 km/s -250 km/s

Dense gas history of the Universe  Tracing the fuel for galaxy formation over cosmic time Millennium Simulations Obreschkow & Rawlings SF Law Primary goal for studies of galaxy formation in next decade! SFR M gas

EVLA/ALMA Deep fields: the‘missing half’ of galaxy formation Volume (EVLA, z=2 to 2.8) = 1.4e5 cMpc galaxies z=0.2 to 6.7 in CO with M(H 2 ) > M o 100 in [CII] z ~ in dust continuum Millennium Simulations Obreschkow & Rawlings

ESO END

CCAT: wide field ‘finder’ surveys