Studying the gas, dust, and star formation in the first
galaxies at cm and mm wavelengths
Chris Carilli, KIAA-PKU reionization workshop, July 2008
 QSO host galaxies at z ~ 6: massive galaxy and SMBH
hole formation within 1Gyr of the Big Bang
 Pushing to normal galaxies with ALMA and the EVLA
USA – Carilli, Wang, Wagg, Fan, Strauss
Euro – Walter, Bertoldi, Cox, Menten, Omont
Why QSO hosts?
 Spectroscopic redshifts
 Extreme (massive) systems
MB < -26 =>
Lbol > 1e14 Lo
MBH > 1e9 Mo
 Rapidly increasing samples:
z>4: > 1000 known
z>5: 80
z>6: 15
Fan 05
QSO host galaxies –
MBH -- Mbulge relation
Magorrian, Tremaine, Gebhardt, Merritt…
 Most (all?) low z spheroidal galaxies have SMBH: MBH=0.002 Mbulge
‘Causal connection between SMBH and spheroidal galaxy formation’
 Luminous high z QSOs have massive host galaxies (1e12 Mo)
MAMBO surveys of z>2 QSOs
1e13 Lo
2.4mJy
• 1/3 of luminous QSOs have S250 > 2 mJy, independent of redshift from
z=1.5 to 6.4
• LFIR ~ 1e13 Lo (HyLIRG) ~ 0.1 x Lbol: Dust heating by starburst or
AGN?
Dust => Gas: LFIR vs L’(CO)
z ~ 6 QSO hosts
Star
formation
rate
1e3 Mo/yr
Index=1.5
1e11 Mo
Gas Mass
 non-linear => increasing SF eff (SFR/gas mass) with increasing SFR
 Massive gas reservoirs > 1010 Mo > 10 x MW
Pushing into reionization: QSO 1148+52 at z=6.4
• Highest redshift SDSS QSO (tuniv = 0.87Gyr)
• Lbol = 1e14 Lo
• Black hole: ~3 x 109 Mo (Willot etal.)
• Gunn Peterson trough (Fan etal.)
1148+52 z=6.42:
Dust detection
MAMBO 250 GHz
3’
S250 = 5.0 +/- 0.6 mJy
LFIR = 1.2e13 Lo
Mdust =7e8 Mo
Dust formation?
• AGB Winds ≥ 1.4e9yr > tuniv = 0.87e9yr
=> dust formation associated with high mass star formation: Silicate
gains (vs. eg. Graphite) formed in core collapse SNe (Maiolino 07)?
1148+52 z=6.42: Gas detection
VLA
CO3-2 VLA
IRAM
PdBI
1” ~ 5.5kpc
+
 Size ~ 5.5 kpc
 M(H2) ~ 2e10 Mo
 ‘Fuel for galaxy
formation’
• FWHM = 305 km/s
• z = 6.419 +/- 0.001
• Mgas/Mdust ~ 30 (~ starburst galaxies)
1148+5251
Radio to nearIR SED
TD = 50 K
Elvis
SED
Radio-FIR correlation
 FIR excess = 50K dust
 Radio-FIR SED follows star forming galaxy
 SFR ~ 3000 Mo/yr
CO excitation ladder
2
NGC253
Dense, warm gas: CO
thermally excited to 6-5,
similar to starburst
nucleus
Tkin > 80 K
nH2 ~ 1e5 cm^-3
MW
Break-down of MBH -- Mbulge relation at very high z
Use CO rotation curves to get host galaxy dynamical mass
High z QSO hosts
Low z QSO hosts
Other low z galaxies
Perhaps black
holes form
first?
Riechers +
Atomic fine structure lines: [CII] 158um at z=6.4
 Dominant ISM gas coolant = star formation tracer
 z>4 => FS lines observed in (sub)mm bands
 [CII] size ~ 6kpc ~ molecular gas => distributed star formation
 SFR ~ 6.5e-6 L[CII] ~ 3000 Mo/yr
Plateau de Bure
IRAM
30m
[CII]
1”
[NII]
[CII] + CO 3-2
[CII] -- the good and the bad
 [CII]/FIR decreases
rapidly with LFIR (lower
heating efficiency due to
charged dust grains?) =>
luminous starbursts are still
difficult to detect in C+
J1623 z=6.25
 Normal star forming
galaxies (eg. LAEs) are not
much harder to detect!
Malhotra + 2000
[CII] in J1623+3111 at z = 6.25
FIR-weaker QSO Host
S250 < 1mJy => FIR < 3e12 Lo
=> Dust detection should not
be a prerequisite for [CII]
search
Bertoldi + 2008
Summary of cm/mm
detections at z>5.7:
33 quasars
 Only direct probe of host galaxies
 10 in dust => Mdust > 1e8 Mo
 5 in CO => Mgas > 1e10 Mo
 10 at 1.4 GHz continuum:
-- SFR > 1000 Mo/yr
-- Radio loud AGN fraction ~ 6%
 2 in [CII] => SFR > 1000 Mo/yr
J1425+3254 CO at z = 5.9
Current Plateau de Bure
is routinely detecting ~
1mJy lines, and 0.1 mJy
continuum at 90GHz!
Building a giant elliptical galaxy
+ SMBH at tuniv < 1Gyr
 Multi-scale simulation isolating most
massive halo in 3 Gpc^3 (co-mov)
10
10.5
Li, Hernquist, Roberston..
8.1
 Stellar mass ~ 1e12 Mo forms in
series (7) of major, gas rich mergers
from z~14, with SFR ~ 1e3 - 1e4 Mo/yr
 SMBH of ~ 2e9 Mo forms via
Eddington-limited accretion + mergers
6.5
 Evolves into giant elliptical galaxy in
massive cluster (3e15 Mo) by z=0
 Generally consistent with
‘downsizing’
• Rapid enrichment of metals, dust in ISM (z > 8)
• Rare, extreme mass objects: ~ 100 SDSS z~6 QSOs on entire sky
• Integration times of hours to days to detect HyLIGRs
Pushing to ‘normal galaxies’ during reionization, eg.
z=5.7 Ly galaxies in COSMOS
NB850nm
Murayama et al. 07
 SUBARU: Ly
 100 deg^-2 in z ~ 5.7 +/- 0.05
~ 10 Mo/yr
Pushing to ‘normal galaxies’ during reionization, eg.
z=5.7 Ly galaxies in COSMOS
Stacking analysis (100 LAEs)
MAMBO: <S250> < 2mJy => SFR<300
VLA Stacking
analysis
 VLA: <S1.4> < 2.5uJy => SFR<125
 Still factor 10 away from SFR(Lya)
Need order magnitude improvement in sensitivity at radio
through submm wavelengths in order to study earliest
generation of normal galaxies.
What is EVLA? First steps to the SKA
By building on the existing infrastructure, multiply ten-fold the
VLA’s observational capabilities, including 10x continuum
sensitivity (1uJy), full frequency coverage (1 to 50 GHz), 80x
BW (8GHz)
Status
•Antenna retrofits now 50% completed.
•Early science in 2010, using new correlator.
•Full receiver complement completed 2012.
What is ALMA?
North American, European, Japanese, and Chilean collaboration to build &
operate a large millimeter/submm array at high altitude site (5000m) in
northern Chile -> order of magnitude, or more, improvement in all areas of
(sub)mm astronomy, including resolution, sensitivity, and frequency coverage.
50 x 12m array
Atacama Compact Array
12x7m + 4x12m TP
ALMA into reionization
Spectral simulation of
J1148+5251
CO
HCO+
HCN
CCH
Detect dust emission in 1sec
(5) at 250 GHz
 Detect [CII] in minutes
 Detect multiple lines,
molecules per band =>
detailed astrochemistry
 Image dust and gas at subkpc resolution – gas dynamics
LAE, LBGs: ALMA will detect dust, molecular, and FS
lines in 1 to 3 hours in normal galaxies at z ~ 6
Pushing to
normal
galaxies:
spectral
lines
cm telescopes: low order
molecular transitions -- total gas
mass, dense gas tracers
(sub)mm: high order
molecular lines. fine
structure lines -- ISM
physics, dynamics
FS lines will be workhorse lines in the study of the first galaxies with ALMA.
Study of molecular gas in first galaxies will be done primarily with cm telescopes
Pushing to normal galaxies: continuum
A Panchromatic view of galaxy formation
Arp 220 vs z
cm: Star formation,
AGN
(sub)mm Dust,
molecular gas
Near-IR: Stars,
ionized gas, AGN
Array operations center at 5000m
AOS Technical Building
Japanese antennas at 3000m
ALMA Status
•Antennas, receivers, correlator fully prototyped, now in production:
best (sub)mm receivers and antennas ever!
•Site construction well under way: Observation Support Facility and
Array Operations Site
•North American ALMA Science Center (C’Ville): gearing up for
science commissioning and early operations
•Timeline
Q1 2007: First fringes at ATF (Socorro)
Q1 2009: Three antenna array at AOS
Q2 2010: First call for (early science) proposals
Q4 2010: Start early science (16 antennas)
Q4 2012: Full operations
ESO
END
ESO
Pushing uJy radio studies to z>2:
Cosmos LBG, BzK, and LAE samples
• 8500 LBGs (U,B,V) identified, z~ 3, 4, 5
• 100 LAE in NB850 filter z = 5.7
• 30,000 BzK star forming galaxies z ~ 1.5 to 2
• ‘normal’ galaxy population at high redshift?
Counterparts
L1.4GHz
> 2.0e+31 erg/s/Hz
M82
(SFR~10)
Arp220
(SFR~100)
M87 (low
lum AGN)
4e+29
4e+30
9e+31
J1000+0234 -- V-drop+radio ID: most distant submm galaxy
Ha + IR: high
extinction
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
1”
UV knot+ Lya
Capak +
Figure 5 - A color image of J1000+0234 with
radio contours
•
•
•
•
V-drop, z>4.5
S1.4 = 45 uJy
S230 = 5 ± 1.4 mJy
Keck spectrum => starburst
galaxy at z = 4.52
• Most distant, spectroscopically
confirmed submm galaxy (the
next most distant at z=3.6)
• Complex optical/IR
morphology: varying extinction
J1000+0234 -- V-drop+radio ID: most distant submm galaxy
VLA CO 2-1
VLA 1.4 GHz
ACS
• CO/radio continuum coincident
with a dust-lane seen rest frame
UV image
• Gass mass ~ 2e10 Mo= fuel for
galaxy formation
• Massive galaxy forming from a
merging system, SFR ~ 3000
Mo/yr
• Comparison to uv-derived SFR
=> uv extinction factor ~100
LBG Stacking
(SKA Science without the SKA)
• Find the average properties
of our “non-detections”
using stacking: reduces noise
by ~ √N.
• Mean stacking: exclude 3,
4 sources: significantly
affects results
• Median stacking does not
require source exclusion, and
is more robust calculation
(see FIRST analysis by
White et. al, 2006)
U-Dropouts (2.5 < z < 3.5)
 <SFRuv> ~ 17 Mo/yr
Median Flux Density =
0.90+/-0.21 Jy
 <SFRrad> ~ 31 Mo/yr
 UV either extinction ~ factor 2
(vs. standard LBG factor 5)
 or Radio-FIR correlation fails at
high z?
BzK galaxies: Star forming galaxies at z~ 1.5 to 2
(Pannella et al)
Star forming galaxies with stellar masses ~ 1e10 to 1e11 Mo
SFR ~ 30 -- 50 Moyr
1.4 GHz vs. Stellar Mass
Stacking detections ~ 2 to 9 +/- 0.2 uJy
1.4 GHz vs. B-z
Specific star formation rate (= SFR/M*) vs. stellar
mass: radio vs. UV data
 Radio: no dust-bias =>
SSFR ~ constant w. M*
Radio SFR
 UV not corrected for dust:
more massive SF galaxies
with higher SFR are also
more extincted
UV SFR
1.4GHz vs. BAB