EVLA + ALMA represent > 10x improvement in observational capabilities from 1GHz to 1 THz

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1 What is EVLA? Build on existing infrastructure, replace all electronics (correlator, Rx, IF, M/C) => multiply ten-fold the VLA s observational capabilities 80x Bandwidth (8 GHz, full stokes), with 4000 channels Full frequency coverage (1 to 50 GHz) 10x continuum sensitivity (<1uJy) 30% FBW at 20GHz => Large volume high z line surveys (eg. z =3.2 to 5.0 in CO 1-0 in K) EVLA + ALMA represent > 10x improvement in observational capabilities from 1GHz to 1 THz

2 EVLA Status Digital retrofits 100% complete Receivers 100% complete at ν 18GHz w. 2GHz BW Full receiver complement completed GHz BW Early science started March 2010 using new correlator Today w. 2GHz BW

3 EVLA (and GBT!) and galaxy formation 100 M o yr -1 at z=5 cm telescopes: low order molecular transitions = total gas mass, dense gas tracers Synchrotron + Free-free continuum = SFR (sub)mm: high order molecular lines. fine structure lines, dust continuum

4 1.4 GHz Source Counts: ujy sky will light up with SF galaxies AGN steep flat starbursts Star forming galaxies spirals 1st/NVSS 3C EVLA ujy ~ 10 4 galaxies per pointing in 12hr

5 Radio stacking of 30,000 sbzk galaxies in COSMOS: Large disk galaxy formation at z ~ 2 M * = M o Stacking in bins of x10 11 M o 0.9 +/- 0.2uJy => SFR ~ 20 M o /yr 20uJy SFR independent B AB Extinction increases SFR increases w. with SFR stellar mass Pannella ea.

6 Dawn of Downsizing: SFR/M * vs. M * 1.4GHz SSFR 5x UV SSFR z=2.1 z=1.5 t -1 H (z=1.8) z=0.3 SSFR constant with M *, unlike z<1 z>1.5 sbzk well above the red and dead line (t h -1 ) => even large galaxies actively star forming UV dust correction = f(sfr, M * ) EVLA will sbzk individually over wide fields

7 EVLA early science: molecular gas across cosmic time I. Quasar host galaxies at z ~ 6 SDSS z = 5.8 CO kpc 500 km/s Wang, Wagg ea Very highly excited M BH ~ 10 9 M o H 2 mass ~ few x (α/0.8) M o SFR ~ 10 3 M o /yr => very early formation of SMBH + massive galaxies at t univ < 1Gyr

8 II. GN20 molecule-rich proto-cluster at z=4 (Daddi ea) CO 2-1 in 3 submm galaxies, all in 256 MHz band 0.3mJy z= mJy CO2-1 46GHz SFR ~ 10 3 M o /year 0.4mJy M gas ~ (α/0.8) M o Early, clustered massive galaxy formation 1000 km/s

9 Spectroscopic imaging GN20 z=4.0 EVLA: well sampled velocity field +250 km/s -250 km/s CO 1-0 region ~ 15 kpc Rotating disk + possible tidal tail Dynamical mass = 3e11 M o Gas mass = 1.3e11 M o Stellar mass = 2.3e11 M o => Baryon dominated

10 EVLA: well sampled velocity field GN20 CO High and low excitation components Clumpy, rotating CO disk ~ 10kpc clumps resolved, sizes >~ 1 kpc clumps H 2 masses ~ 10 9 to M o => Dekel Disk : Cold Mode Accretion scales up to SMGs at t univ < 2Gyr?

11 III. CO observations of sbzk with EVLA/Bure: Massive gas reservoirs without extreme starbursts (Daddi, Aravena, Dannerbauer) CO 1-0 EVLA z ~ of 6 sbzk detected in CO with Bure and/or EVLA, sizes > 10kpc Gas masses ~ M o ~ gas mass in SMG, but SFR < 10% SMG Gas masses stellar masses => pushed back to epoch when galaxies are gas dominated!

12 SMG/QSO Lower CO excitation ~ MW [low J observations are key!] FIR/L CO: Gas consumption timescales ~ few x10 8 yrs ~ MW secular formation of large disk galaxies during epoch of galaxy assembly (Genzel, Tacconi, Daddi ) high z Universe is rich in molecular gas!

13 Higher Density Tracers: Realm of cm telescopes! z=2.6 HCN uJy n cr > 10 5 cm -3 (vs. n cr (CO) ~ 10 3 cm -3 ) => high order transitions hard to excite Linear correlation with SFR => [SFR/dense gas] ~ constant ( counting SF clouds ) HCO+ 1-0 Index = 1 Gao +, Wu +

14 Dense gas history of the Universe Tracing the fuel for galaxy formation over cosmic time sbzk BX/BM SFR SF Law Millennium Simulations Obreschkow & Rawlings See also Bauermeister et al. M gas DGHU is primary goal for studies of galaxy formation this decade!

15 z ~ 3 Lensed LBG Riechers ea Next proposal deadline is February 1, 2011

16 END

17 EVLA/ALMA Deep fields: the missing half of galaxy formation 1000 hrs, 50 arcmin 2 Volume (EVLA Ka, CO 1-0 at 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

18 GN20 CO EVLA: well 0.18 sampled velocity field Regions of active star formation are totally obscured in HST ACS image Clumpy, rotating CO disk ~ 10kpc clumps resolved, sizes >~ 1 kpc clumps H 2 masses ~ 10 9 to M o => Dekel Disk : Cold Mode Accretion scales up to SMGs at t univ < 2Gyr?

19 Spectroscopic imaging GN20 z=4.0 EVLA: well sampled velocity field CO 1-0 region ~ 15 kpc Rotating disk + possible tidal tail Dynamical mass = 3e11 M o Gas mass = 1.3e11 M o Stellar mass = 2.3e11 M o => Baryon dominated