Title: Radio astronomical probes of cosmic reionization and the first galaxies
1Radio astronomical probes of cosmic reionization
and the first galaxies Chris Carilli (NRAO),
McGill University, October 2009
- Brief introduction to cosmic reionization
- Objects within reionization recent observations
of molecular gas, dust, and star formation, in
the host galaxies of the most distant QSOs early
massive galaxy and SMBH formation - Neutral Intergalactic Medium (IGM) HI 21cm
telescopes, signals, and challenges - Dramatic advances with next gen instruments
ALMA, EVLA
Wang, Walter, Wagg, Riechers, Fan, Strauss,
Bertoldi, Cox, Menten, Neri
2Ionized
Neutral
Reionized f(HI) lt 10-5
3Chris Carilli (NRAO) Berlin June 29, 2005
WMAP structure from the big bang
4Hubble Space Telescope Realm of the Galaxies
5Dark Ages
- Last phase of cosmic evolution to be tested
- Bench-mark in cosmic
- structure formation
- indicating the first
- luminous structures
Cosmic Reionization
6Constraint I Gunn-Peterson Effect
z
Barkana and Loeb 2001
7Constraint I Gunn-Peterson Effect
- End of reionization?
- f(HI) lt1e-4 at z 5.7
- f(HI) gt1e-3 at z 6.3
- Limitation Universe becomes optically thick at
low f(HI)
Fan et al 2006
8Constraint II CMB large scale polarization
Thomson scattering during reionization
- Scattering CMB local quadrapole gt polarized
- Large scale horizon scale at reioniz 10s deg
- Signal is weak
- TE 10 TT
- EE 1 TT
Hinshaw et al 2008
?e 0.084 /- 0.016
9Constraint II CMB large scale polarization
- Rules-out high ionization fraction at zgt 15
- Allows for finite (0.2) ionization to high z
- Most action occurs at z 8 to 14
- Limitation broad range in allowed model
parameters
Dunkley et al. 2008
10Fan, Carilli, Keating ARAA 06
ltVolgt
GP gt First light occurs in twilight zone,
opaque for ?obs lt0.9 ?m
- GP gt pushing into tail-end of reionization at z
6 - CMB pol gt substantial ionization fraction
persists to z 11
11Massive galaxy formation at z6 gas, dust, and
star formation in quasar host halaxies
- Radio astronomy unveiling the cool, obscured
Universe - mm continuum thermal emission from warm dust gt
star formation - (sub)mm lines high order molecular lines,
atomic fine structure lines gt ISM physics - (short) cm lines low order molecular lines gt
gas mass, dynamics - cm continuum synchrotron emission gt star
formation, AGN
Wilson et al.
HST / OVRO CO
cm/mm rich in line continuum diagnostics
12Powerful suite of existing telescopes
- IRAM 30m MAMBO sub-mJy sens at 250 GHz
wide fields ? dust - IRAM PdBI sub-mJy sens at 90 and 230 GHz
arcsec resol. ?mol. Gas, CII - VLA uJy sens at 1.4 GHz ? star formation
- VLA lt 0.1 mJy sens at 20-50 GHz 0.2 resol.
? mol. gas (low order)
13SDSS J11485258 z6.42
Why quasars?
- Spectroscopic redshifts
- Extreme (massive) systems
- Lbol 1e14 Lo
- MBH 1e9 Mo
- Rapidly increasing samples
- zgt4 gt 1000 known
- zgt5 gt 100
- zgt6 20
- Note will not discuss MBH
J1148525 VLA CO3-2
14QSO host galaxies MBH -- Mbulge relation
Haaring Rix
- Most (all?) low z spheroidal galaxies have SMBH
MBH0.002 Mbulge - Causal connection between SMBH and spheroidal
galaxy formation - Luminous high z QSOs have massive host galaxies
(1e12 Mo)
15Dust and star formation MAMBO 250GHz surveys 1/3
of zgt2 quasars have S250 gt 2mJy
HyLIRG
- Wang sample 33 quasars at zgt5.7 (mostly SDSS)
- LFIR 0.3 to 1.3 x1013 Lo HyLIRG (47K, ß
1.5) - Mdust 1.5 to 5.5 x108 Mo 10x MW (?125um
19 cm2 g-1)
16- Dust formation at tunivlt1Gyr?
- AGB Winds 1.4e9yr gt dust formation?
- High mass star formation (Dwek, Shull, Nozawa)
- Smoking quasars dust formed in BLR winds
(Elvis) - Extinction toward z6.2 QSO and 6.3 GRB gt
larger, silicate amorphous carbon dust grains
formed in core collapse SNe vs. eg. graphite?
SMC, zlt4 quasars
Galactic
z6.2 quasar, GRB
Maiolino, Stratta
17Dust heating star formation? Radio to near-IR
SED
Elvis SED TD 1000K
TD 47 K
- FIR not correlated with LB
- FIR excess 47K dust
- Radio-FIR SED consistent with star forming
galaxy gt - SFR 400 to 2000 Mo yr-1
Radio-FIR correlation
18Fuel for star formation? Molecular gas 8 CO
detections at z 6 with PdBI, VLA
- Mgas 0.7 to 3 x1010 (a/0.8) Mo
- Accurate redshifts ? z 0.001 (vs. optical ? z
gt 0.03)
19 CO excitation Dense, warm gas, thermalized to
6-5
Tk 50 K nH2 104.2 cm-3
J1148 J1048
Giant Molecular Cloud (50pc) 100 to 1000
cm-3 GMC cores (lt1pc) gt 104 cm-3
20LFIR vs L(CO) integrated Kennicutt-Schmidt SF
law
- Star formation efficiency(SFR/Mgas) increases
with increasing SFR - Gas depletion timescale(Mgas/SFR) decreases with
SFR - Need gas re-supply to build GE
SFR
1e3 Mo/yr
Index1.5
1e11 Mo
Mgas
FIR 1e10 Lo/yr gt tdep 3e8yr FIR 1e13
Lo/yr gt tdep 1e7yr
21114852 z6.42 VLA imaging at 0.15 resolution
CO3-2 VLA
IRAM
0.3
1 5.5kpc
- Size 6 kpc
- Two peaks separated by 2kpc with sizes 1kpc,
M(H2) 5 x109 Mo - TB 35 K gt approaching optically thick
22Gas dynamics CO velocities
z4.19
z4.4
-150 km/s
150 km/s
- Dynamical mass (r lt 3kpc) 0.4 to 2 x1011 Mo
- M(H2)/Mdyn gt 10
23Break-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? but Lauer Bias
for optically selected quasars or All highly
inclined i lt 20o
Riechers
24CII 158um (2P3/2 - 2P1/2)
- Dominant ISM gas cooling line (Spitzer 1976)
- Traces CNM and PDRs
- COBE CII 10x more luminous than any other mm
to FIR line in MW 1 Lgal - zgt4 gt FS lines observed in (sub)mm bands at zgt6
gt Bure!
Bennett et al.
25CII 158um search in z gt 6.2 quasars
- J11485251 z6.42
- SCII 10mJy
- LCII 4x109 Lo (LNII lt 0.1LCII )
- J16233112 z6.25
- SCII 3mJy
- S250GHz lt 1mJy
Kundsen, Bertoldi, Walter, Maiolino
26Maximal star forming disk (Walter 2009)
1
PdBI 250GHz 0.25res
- CII size 1.5 kpc gt SFR/area 1000 Mo yr-1
kpc-2 - Maximal starburst (Thompson, Quataert, Murray
2005) - Self-gravitating gas disk
- Vertical disk support by radiation pressure on
dust grains - Eddington limited SFR/area 1000 Mo yr-1 kpc-2
- eg. Arp 220 on 100pc scale, Orion SF cloud cores
lt 1pc
27Summary of cm/mm observations of 33 quasar host
galaxies at zgt5.7
J14253254 CO at z 5.9
J1048 z6.23 PdBI, VLA
- Only direct probe of host galaxies of most
distant quasars - 11 in dust gt Mdust gt 1e8 Mo Dust formation in
Sne? - 10 at 1.4 GHz continuum Radio FIR SED gt SFR
1000 Mo/yr - 8 in CO gt Mgas gt 1e10 Mo Fuel for star
formation in galaxies, GMC core conditions over
kpc-scales - 2 in CII gt maximal star forming disk 1000
Mo yr-1 kpc-2
28Building a giant elliptical galaxy SMBH at
tunivlt 1Gyr
10
- Multi-scale simulation isolating most massive
halo in 3 Gpc3 - Stellar mass 1e12 Mo forms in series (7) of
major, gas rich mergers from z14, with SFR ? 1e3
Mo/yr - SMBH of 2e9 Mo forms via Eddington-limited
accretion mergers - Evolves into giant elliptical galaxy in massive
cluster (3e15 Mo) by z0
6.5
Li, Hernquist et al.
Li, Hernquist
- Rapid enrichment of metals, dust in ISM (z gt 8)
- Rare, extreme mass objects 100 SDSS z6 QSOs
on entire sky
29Cosmic Stromgren Sphere
- Accurate host redshift from CO z6.419/0.001
- Proximity effect photons leaking from
6.32ltzlt6.419
White et al. 2003
z6.32
- time bounded Stromgren sphere R 4.7 Mpc
- tqso 1e5 R3 f(HI) 1e7yrs
- f(HI) 1 (tqso/1e7 yr)
30CSS 24 quasars with accurate zGP, zhost (mostly
CO, MgII)
- ltRpgt 7.3 Mpc gt f(HI) 0.05 at z6 for
tqso 107 yrs - Decrease ltRpgt from 9.4 Mpc at z5.7 to 4.0 Mpc
at z6.4 gt increase in f(HI) by factor 9
Fan
Rp 7.3 7.1(z-6) Mpc
31Fan, Carilli, Keating ARAA 2006
- Not event but complex process, large
variance zreion 14 to 6 - Good evidence for qualitative change in nature
of IGM at z6
ESO
32Local ioniz.?
- Current probes are all fundamentally limited in
diagnostic power - Need more direct probe of process of reionization
ESO
33Studying the pristine neutral IGM using
redshifted HI 21cm observations (100 200 MHz)
- Large scale structure
- cosmic density, ?
- neutral fraction, f(HI)
- Temp TK, TCMB, Tspin
1e13 Mo
1e9 Mo
34Pathfinders 1 to 10 SKA
21CMA (China) 10,000 Dipole array working in
Western China 2008
MWA (MIT/CfA/ANU) 32 Tile array deployment in WA
2009
Site Type Freq MHz Area m2 Goal Date
GMRT India Parabola 150-165 4e4 CSS 2009
21CMA China Dipole 70-200 1e5 PS 2008
PAPER GB/Oz/SA Dipole 110-200 5e3 PS/CSS 2009
MWAdemo Oz Aperture 80-300 1e4 PS/CSS 2009
LOFAR NL Aperture 115-240 1e5 PS/CSS 2010
SKA ?? Aperture 30-300 1e6 Imaging ??
35Signal I HI 21cm Tomography of IGM Furlanetto,
Zaldarriaga 2004
9
z12
- ?TB(2) 10s mK
- SKA rms(100hr) 4mK
- LOFAR rms (1000hr) 80mK
7.6
36Signal II 3D Power spectrum analysis
? only
LOFAR
? f(HI)
SKA
McQuinn 06
37Signal III IGM after reionization cosmic web
Ly alpha forest at z3.6 (? lt 10)
Womble 96
- N(HI) 1013 1015 cm-2, f(HI/HII) 10-5 --
10-6 gt before reionization N(HI) 1018 1021
cm-2 - ?Lya 107 ?21cm gt neutral IGM opaque to Lya,
but translucent to 21cm
38Signal III Cosmic web before reionization HI
21Forest
z12
z8
19mJy
130MHz
159MHz
- Perhaps easiest to detect
- Only probe of small scale structure
- Requires radio sources expect 0.05 to 0.5 deg-2
at zgt 6 with S151 gt 6 mJy?
- radio G-P (?1)
- 21 Forest (10)
- mini-halos (10)
- primordial disks (100)
39Signal IV Cosmic Stromgren spheres around z gt 6
QSOs
- LOFAR observation
- 20xf(HI)mK, 15,1000km/s
- gt 0.5 x f(HI) mJy
- Pathfinders Set first hard limits on f(HI) at
end of cosmic reionization
5Mpc
Wyithe et al. 2006
Prediction first detection of HI 21cm signal
from reionization will be via imaging rare,
largest CSS
0.5 mJy
40Challenge I Low frequency foreground hot,
confused sky
0.5 to 5.0 GHz
Haslam Eberg 408MHz
- Coldest regions T 100 (?/200 MHz)-2.6 K
- Highly confused 1 source/deg2 with S140 gt 1
Jy - Synch. smooth 100MHz vs. 21cm lines 1 MHz
- Dynamic range gt daily calibration errors lt 0.2
(Datta )
41Challenge II Ionospheric phase errors varying
e- content
- TIDs fuzz-out sources
- Isoplanatic patch few deg few km
- Phase variation proportional to ?2
- Solution Wide field rubber screen phase
self-calibration using data-rich sky
15
Virgo A VLA 74 MHz Lane 02
42Challenge III Interference
100 MHz z13
200 MHz z6
- Solutions -- RFI Mitigation (Ellingson06)
- Digital filtering
- Beam nulling
- Real-time reference beam
- LOCATION!
Aircraft
Orbcom
TV
43VLA-VHF 180 200 MHz Prime focus X-dipole
Greenhill, Blundell (SAO) Carilli, Perley (NRAO)
Leverage existing telescopes, IF, correlator,
operations
- 110K DD/construction (CfA)
- First light Feb 16, 05
- Four element interferometry May 05
- First CSS detection Winter 06/07
44Project abandoned Digital TV
KNMD Ch 9 150W at 100km
45RFI mitigation location, location location
100 people km-2
1 km-2
0.01 km-2
Chippendale Beresford 2007
46PAPER Precisions Array to Probe the Epoch of
Reionization PI Backer (UCB), Bradley
(NRAO) Western Australian deployment in 2008
- Optimize for reionization PS/CSS
- FoV 30deg, short baselines lt 0.6km
- Staged engineering GB06 8 stations ? WA08 8
stations ? SA09 32
47PAPER Staged Engineering
- Broad band sleeve dipole flaps
- FPGA-based pocket correlator from Berkeley
wireless lab - S/W Imaging, calibration, PS analysis AIPY
Miriad/AIPS gt Python CASA, including
ionospheric peeling calibration
100MHz
200MHz
Beam response
BEE2 5 FPGAs, 500 Gops/s
48PAPER in Green Bank2008 Mar
130-170 MHz 7 Dipole 24-hour integration
Parsons 2009
- Current arrays First light at 1 Jy rms
- Long campaigns in WA/SA in 2010 gt first limits
to PS/CSS?
49Giant steps in cm First galaxies and the EVLA
- By building on the existing infrastructure,
multiply ten-fold the VLAs observational
capabilities, including - 10x continuum sensitivity (lt1uJy)
- full frequency coverage (1 to 50 GHz)
- 80x BW (8GHz)
- Critical element Canadian WIDAR correlator
(DRAO)!
50Giant steps in (sub)mm First galaxies and
ALMA North American, European, Japanese, and
Chilean collaboration to build operate a large
millimeter/submm array at high altitude site
(5000m) in northern Chile -gt 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
51Pushing to normal galaxies spectral lines
100 Mo yr-1 at z5
cm telescopes low order molecular transitions --
total gas mass, dense gas tracers
(sub)mm high order molecular lines. fine
structure lines -- ISM physics, dynamics
52Pushing to normal galaxies continuum A
Panchromatic view of 1st galaxy formation
100 Mo yr-1 at z5
cm Star formation, AGN
(sub)mm Dust, FSL, mol. gas
Near-IR Stars, ionized gas, AGN
53- EVLA Status
- Antenna retrofits now 50 completed.
- Early science start in Q1 2010 using new
correlator, proposal deadline Oct 1, 2009 - Full receiver complement completed 2012.
54AOS Technical Building
- ALMA status
- Antennas, receivers, correlator in production
best submm receivers and antennas ever! - Site construction well under way Observation
Support Facility, Array Operations Site, first
antennas at high site
Array operations center
Antenna commissioning in progress
- North American ALMA Science Center (CVille)
support early science Q4 2010, full ops Q4 2012
55- Probing the Dark Ages using a Lunar low frequency
array - No interference
- No ionosphere
- Only place to study dark ages (lt 60 MHz)
10MHz
Recognized as top astronomy priority for NASA
initiative to return Man to Moon (Livio 2007)
RAE2 1973
56J. Burns, PI Colorado
A2010 White paper lunar radio array (Lazio
) http//lunar.colorado.edu/
57END
ESO
58CII
z gt4
- CII/FIR decreases with LFIR lower gas
heating efficiency due to charged dust grains gt
luminous starbursts are still hard to detect in
C - Normal star forming galaxies are not much harder
to detect - HyLIRG at zgt 4 no worse than low z ULIRG
- Dont pre-select on dust
Malhotra, Maiolino, Bertoldi, Knudsen, Iono,
Wagg
59Sources responsible for reionization
- Luminous AGN No
- Star forming galaxies maybe -- dwarf galaxies
(Bowens05 Yan04)? - mini-QSOs -- unlikely (soft Xray BG Dijkstra04)
- Decaying sterile neutrinos -- unlikely (various
BGs Mapelli05) - Pop III stars zgt10? midIR BG (Kashlinsky05),
but trecomb lt tuniv at z10
Needed for reion.
60Signal I Global (all sky) reionization
signature
Signal 20mK lt 1e-4 sky
Feedback in Galaxy formation No Feedback
Possible higher z absorption signal via Lya
coupling of Ts -- TK due to first luminous
objects
Furlanetto, Oh, Briggs 06
61S?
M82 radio-FIR SED All mechanisms ? massive star
formation rate
Thermal dust 20 -- 70K
z
Synchrotron
Radio-FIR
Free-Free
SFR (Mo/yr) 3e-10 LFIR (Lo/yr) SFR (Mo/yr)
6e-29 L1.4 (erg/s/Hz) ? (ULIRGs) 0.8 Mo (K km
s-1 pc2)-1
62Building a giant elliptical galaxy SMBH at
tunivlt 1Gyr
10
- Multi-scale simulation isolating most massive
halo in 3 Gpc3 - Stellar mass 1e12 Mo forms in series (7) of
major, gas rich mergers from z14, with SFR ? 1e3
Mo/yr - SMBH of 2e9 Mo forms via Eddington-limited
accretion mergers - Evolves into giant elliptical galaxy in massive
cluster (3e15 Mo) by z0
6.5
Li, Hernquist et al.
- Rapid enrichment of metals, dust in ISM (z gt 8)
- Rare, extreme mass objects 100 SDSS z6 QSOs
on entire sky
63Radio astronomy probing cosmic reionization
- GP gtTwilight zone obs of 1st galaxies
limited to near-IR to radio - Current mm/cm observations reveal coeval
formation SMBH giant elliptical galaxies in
spectacular starbursts at tunivlt1Gyr - Low freq pathfinders HI 21cm signatures of
neutral IGM - SKA imaging of IGM
64Chromatic aberration Frequency differencing with
MHz channels doesnt work well due to frequency
dependent far-out sidelobes
142, 174 MHz
Datta
- Dynamic range requirements on calibration errors
- Daily cal errors lt 0.2
- Monthly cal errors lt 0.01