ALMA: Resolving (optically) obscured galaxy formation
Dusty04, C. Carilli (NRAO)
Franceschini 2000
srmnWdIm
m
//30)( 21000
100
srmnWdIm
m
//17)( 230
3.0
Cosmic Background Radiation
IR Optical
Obscured galaxy formation: low redshift (Meier & Turner 2004)
IC342
distance = 2 Mpc
M_gas = 4e7 M_sun
SFR = 0.1 M_sun/yr
Starburst age = 1e7 yrs
30” = 300pc
PdBI/VLA position =>
K = 23.5 (Dunlop et al.)
I – K > 5.2
z = 4 +/- 1 (?)
S_250 = 2.1 +/- 0.3 mJy
S_1.4 = 16 +/- 4 uJy
L_FIR=7e12 L_sun
Grav. Mag. = 3x (?)
Obscured galaxy formation: high redshift (Downes et al 2002; Dunlop et al 2003)
Single Scuba galaxy dominates SFR at z>2 in HDF over 10000 optical galaxies!
UV selected galaxies – large range in bolometric luminosity, but little correlation of L_uv and L_bol
Adelberger 2000
Magic of (sub)mm
L_FIR = 4e12 x S_250(mJy) L_sun for z=0.5 to 8
Enabling Technology I: sensitivity – Arp 220 vs z (FIR=1.6e12 L_sun)
cm: Star formation, AGN
(sub)mm Dust, molecular gas
Near-IR: Stars, ionized gas, AGN
Enabling technology II: Resolution
10’s mas resolution, T_B = 0.3 K: GMCs at 200Mpc
PdBI/CARMA
ALMA
Nearby star forming Galaxies – Chemistry/Physics: IC342, D=2Mpc
CO: all gas
HC3N: Dense
C2H: PDRs
ALMA: Image with GMC resolution (50pc) to 250 Mpc
Rich clusters: Virgo = 16 Mpc, Coma = 100 Mpc
ULIRGs: Arp 220 = 75 Mpc, Mrk 273 = 160 Mpc
300pc
Meier & Turner 2004
Nearby Gals II: Dynamics: ‘feeding the nucleus’ – NGC6946, D=5.5Mpc
100 pc
PdBI 0.5” CO(2-1) - Gas Lanes along Bar - Streaming Motions - Gas Disk w/ R <15pc
ALMA: extend toMrk 231 at 180 MpcCygnus A at 240 Mpc
Schinnerer et al., in prep.
Probing the epoch of “galaxy formation” : z = 1.5 – 3.5
Comparable SFR at high z in dusty starbursts as optical galaxies?
IR/(sub)mm gals
Optical gals
(sub)mm Source counts (Blain 2002)
ALMA: 2e6 gals/deg^2
HDF: 4e6 gals/deg^2
Big Difference:
ALMA gals (mostly) at z > 1
HST gals (mostly) at z < 1
Current bolometers
Lensed fields
ALMA
L_FIR vs L’(CO) (Beelen + 04)
Index=1.7
Index=1
1e11 M_sun
1e3 M_sun/yr
ALMA z>2
PdBI/Carma z>2
SKA and ALMA: Optimal CO searches
ALMA: discovers 10 gals/hr z=0.5 – 2.5
SKA: discovers 10 gals/hr z=4
HCN 1-0 emission: VLA detections
n(H_2) > 1e5 cm^-3 (vs. CO: n(H_2) > 1e3 cm^-3)
z=2.58
Solomon et al
Index=1
70 uJy
Current z>2
ALMA z>2 (if constant T_b)
Main ISM cooling line:
[CII] 158um (vd Werf 2004)
PKS 2322+1944 z=4.12: CO Einstein ring
PdBI [CI] (492 GHz rest) => Solar Metallicity (Pety 2004)
PdBI
VLA CO2-1 0.4” res
Very wide field surveys: role of bolometer cameras
Bolometers (+ EVLA, Spizter): survey large areas to sub-mJy sensitivity
ALMA: detailed SED and CO follow-up
ALMA: uJy, narrow field surveys
Enabling technology III: Wideband spectroscopy – Redshifts for obscured/faint sources: 8 - 32 GHz spectrometers on ALMA, LMT, GBT (Min Yun 04, Harris 04)
L_FIR = 1e13 L_sun
ALMA
History of IGM
• bench-mark in cosmic structure formation indicating the first luminous structures
Epoch of Reionization (EoR)
ionized
Neutral F(HI)=1
Ionized F(HI)=1e-5
CoIs: Walter, Bertoldi, Cox, Omont, Beelen, Fan, Strauss...
z=5.80
z=5.82
z=5.99
z=6.28
The Gunn-Peterson Effect
Fan et al 2003
Fast reionization at z=6.3
=> opaque at _obs<0.9m
1e-5
1e-3
Thompson scattering at EoR
e = 0.17 => F(HI) < 0.5 at z=17
Complex reionization from z=6 to 15?
WMAP Large scale polarization of CMB (Kogut et al.)
20deg
•highest redshift quasar known•L_bol = 1e14 L_sun
•central black hole: 1-5 x 109 Msun => M_bulge = 1.5e12 M_sun (Willot etal.)
•clear Gunn Peterson trough (Fan etal.)
Objects within EoR – QSO 1148+52 at z=6.4
“Pre-ALMA Science” – 1148+52 Dust + CO detection z=6.42
• S_250 = 5.0 mJy => L_FIR = 1.2e13 L_sun, M_dust=7e8 M_sun
• S v = 0.2 Jy km/s => M(H_2) = 2e10 M_sun
3’
MAMBOVLA CO 3-246.6149 GHz
Off channelsrms = 60 uJy
Prodigious dust and molecular gas formation within 0.9 Gyr of big bang
eg. Dust formation in SNR/massive stars?
IRAM Plateau de Bure
• FWHM = 305 km/s• z = 6.419 +/- 0.001
(3-2)(7-6)
(6-5)
• Tkin=100K, nH2=105cm-3
Typical of starburst nucleus
VLA imaging of CO3-2 at 0.4” and 0.15” resolution
Separation = 0.3” = 1.7 kpc
T_B = 20K = T_B (starburst)
Merging galaxies?
Or Dissociation by QSO?
rms=50uJy at 47GHz
CO extended to NW by 1” (=5.5 kpc) tidal(?) feature
M_dyn (r<2.5kpc) = 5e10 M_sun
=> break-down of M-relation => SMBH form first?
1148+5251: radio-FIR SED
Star forming galaxy characteristics: radio-FIR SED, L’_CO/FIR, CO excitation and T_B => Coeval starburst/AGN: SFR = 1000 M_sun/yr
Stellar spheroid formation in few e7 yrs = e-folding time for SMBH
=> Coeval formation of galaxy/SMBH at z = 6.4 ?
S_1.4= 55 +/- 12 uJy
1048+46
Beelen et al.
T_D = 50 K
Objects within the EoR – nearIR detection of ‘normal’ star forming galaxy at z=6.56 (Hu et al)
L_uv = 2e10 L_sun + LBG dust correction (5x) => L_FIR=1e11 L_sun
S_250 = 0.03 mJy => 4 ALMA detection in 3 hrs
Expect 1 – 2 “normal” galaxies ALMA FoV at z>6
ALMA – de-obscuring galaxy formation
I. Seeing through the dust:
• Physics, chemistry, dynamics of star formation at GMC scale to 250Mpc
• Unveiling the “submm” galaxy population at z=1 to 3 => ½ SFHU
II. First light: Seeing through neutral IGM (GP=> limited to NIR to radio)
• Study dust, gas, star formation in the first luminous sources
• Currently limited to pathological systems (‘HLIRGs’)
• ALMA, EVLA 10-100x sensitivity is critical to study normal galaxies
z
mm VLBI
10’s as resolution
PdBI/CARMA
ALMAmmVLBI
Millimeter VLBI – Imaging the Galactic center black hole (Falcke 2000)
Kerr
Schwarzschild
Model: opt. thin synch
0.6 mm VLBI
16uas res
1.3 mm VLBI
33 uas res
R_g = 3 uas
mm-vlbi of the Galactic center
(Krichbaum 1998)
