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. Digital retrofits 100% complete
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 Mo yr-1 at z=5
cm telescopes: low order molecular transitions = total gas mass, dense gas tracers
(sub)mm: high order molecular lines. fine structure lines, dust continuum
Synchrotron + Free-free continuum = SFR

4. EVLA uJy ~ 104 galaxies per pointing in 12hr
1.4 GHz Source Counts: uJy sky will ‘light up’ with SF galaxies
AGN
steep
flat
starbursts
spirals
Star forming galaxies
1st/NVSS C
EVLA uJy ~ 104 galaxies per pointing in 12hr

5. Radio stacking of 30,000 sBzK galaxies in COSMOS:
Large disk galaxy formation at z ~ 2
M*= 1010 Mo
Stacking in bins of 3000
3x1011 Mo
0.9 +/- 0.2uJy => SFR ~ 20 Mo/yr
20uJy
SFR independent BAB
Extinction increases with SFR
SFR increases w. stellar mass
Pannella ea.

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

7. EVLA early science: molecular gas across cosmic time
I. Quasar host galaxies at z ~ 6
SDSS z = 5.8
CO 2-1
500 km/s
11kpc
Very highly excited
Wang, Wagg ea
MBH ~ 109 Mo
H2 mass ~ few x 1010 (α/0.8) Mo
SFR ~ 103 Mo/yr
=> very early formation of SMBH + massive galaxies at tuniv < 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=4.055
4.051
4.056
0.7mJy
CO2-1 46GHz
0.4mJy
SFR ~ 103 Mo/year
Mgas ~ (α/0.8) Mo
Early, clustered massive galaxy formation
1000 km/s

9. EVLA: well sampled velocity field
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 Mo
Gas mass = 1.3e11 Mo
Stellar mass = 2.3e11 Mo
=> Baryon dominated

10. EVLA: well sampled velocity field
GN20 CO ”
EVLA: well sampled velocity field
0.18”
High and low excitation components
Clumpy, rotating CO disk ~ 10kpc
clumps resolved, sizes >~ 1 kpc
clumps H2 masses ~ 109 to 1010 Mo
=> ‘Dekel Disk’: Cold Mode Accretion scales up to SMGs at tuniv < 2Gyr?

11. (Daddi, Aravena, Dannerbauer)
III. CO observations of sBzK with EVLA/Bure: Massive gas reservoirs without extreme starbursts
(Daddi, Aravena, Dannerbauer)
CO 1-0 EVLA z ~ 1.5
6 of 6 sBzK detected in CO with Bure and/or EVLA, sizes > 10kpc
Gas masses ~ 1011 Mo ~ gas mass in SMG, but SFR < 10% SMG
Gas masses ≥ stellar masses => pushed back to epoch when galaxies are gas dominated!

12. Lower CO excitation ~ MW [low J observations are key!]
SMG/QSO
1.5 1
Lower CO excitation ~ MW [low J observations are key!]
FIR/L’CO: Gas consumption timescales ~ few x108 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
ncr > 105 cm-3 (vs. ncr(CO) ~ 103 cm-3) => high order transitions hard to excite
Linear correlation with SFR => [SFR/dense gas] ~ constant (‘counting SF clouds’)
z=2.6 HCN uJy
Index = 1
Gao +, Wu +
HCO+ 1-0

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

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

16. END

17. Millennium Simulations Obreschkow & Rawlings
EVLA/ALMA Deep fields: the ‘missing half’ of galaxy formation
1000 hrs, 50 arcmin2
Volume (EVLA Ka, CO 1-0 at z=2 to 2.8) = 1.4e5 cMpc3
1000 galaxies z=0.2 to 6.7 in CO with M(H2) > 1010 Mo
100 in [CII] z ~ 6.5
5000 in dust continuum
Millennium Simulations Obreschkow & Rawlings

18. EVLA: well sampled velocity field
GN20 CO ”
EVLA: well sampled velocity field
0.18”
Regions of active star formation are totally obscured in HST ACS image
Clumpy, rotating CO disk ~ 10kpc
clumps resolved, sizes >~ 1 kpc
clumps H2 masses ~ 109 to 1010 Mo
=> ‘Dekel Disk’: Cold Mode Accretion scales up to SMGs at tuniv < 2Gyr?

19. EVLA: well sampled velocity field
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 Mo
Gas mass = 1.3e11 Mo
Stellar mass = 2.3e11 Mo
=> Baryon dominated