The Atacama Large Millimeter Array: Imaging the Cool Universe

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The Atacama Large Millimeter Array Imaging the
Cool Universe

• C. Carilli (NRAO)
• UCSD
• Jan 2008

National Research Council Canada
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(sub)mm astronomy unveiling the cold, obscured
universe
SCUBA
Wilson et al.
Shirley et al.
B335 DSS
HST / OVRO CO
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Cosmic BackgroundRadiation
Submm
Franceschini 2000
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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 -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
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Technical Specifications

• 50 12-m antennas, 12 7-m antennas, 4 12-m with
  nutators (TP)
• Chajnantor 5000 m altitude site.
• Surface accuracy ?25 ?m, 0.6 reference pointing
  in 9m/s wind, 2 absolute pointing all-sky.
• Array configurations between 150m to 18km (ACA)
• 10 bands in 31-950 GHz 183 GHz WVR. Initially
• 86-119 GHz 3 125-169 GHz
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• 211-275 GHz 6 275-370 GHz
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• 385-500 GHz 8 602-720 GHz
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• 8 GHz BW, dual polarization.
• Flux sensitivity 0.2 mJy in 1 min at 345 GHz
  (median cond.).
• Interferometry, mosaicing total-power
  observing.
• Correlator 4096 channels/2GHz IF, full Stokes.
• Data rate 6MB/s average peak 60-150 MB/s.
• All data archived (raw images), pipeline
  processing.

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Giant Steps I Frequency and resolution
20mas at 0.9THz (300um)
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Giant Steps II Sensitivity
Index1.7
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Giant Steps III Image quality w. 50x12m, 12x7m,
4x12m w/ TP
HST quality imaging through with dense sampling
of uv plane

• TBline sub-K at 0.25
• TBcont mK at 0.25

ACATP
Takakuwa et al. 2006
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Giant Steps IV Site quality
? 0.5 at 0.9 THz (300um)
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Giant Steps V Broad Band Spectroscopy 2pol x
8GHz x 16k ch Birth of stars astrochemistry
machine in 3D

• Line confusion limited gt new mode of operation
  targeted line studies
• Select lines as probes of density, temperature,
  excitation, evolutionary state, or dynamics
• Puts pressure on laboratory astrophysics, and
  data analysis/visualization S/W

(Ziurys et al.)
SgrB2(N) 1 GHz spectrum using Band 6 mixer at the
SMT
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Birth of planets

• Mplanet / Mstar 0.5 MJup / 1.0 Msun
• Orbital radius 5AU at 50pc distance
• Disk mass circumstellar disk around the
  Butterfly Star in Taurus

ALMA 850 GHz 20mas
Williams et al.
HST
Wolf Simulation of nearby PP disk (eg. TW Hy)
5AU 0.1
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Massive star formation protostellar disk
chemistry and dynamics in highly obscured regions
700AU
Brogan
Krumholz
ALMA Disk dynamics and physical conditions at
resolution 10s AU, few km/s
SMA CephA-East hot core HW2 (725pc) Disk,
Double, or Outflow?
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Magic of (sub)mm cosmology distance
independent method of studying objects in
universe from z0.8 to 10 LFIR 4e12 x S250(mJy)
L_sun SFR 1e3 x S250 M_sun/yr
current state-of-art
?obs 250GHz
FIR 1.6e12 L_sun
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Submm surveys Probing the epoch of galaxy
formation (z1.5 3)
SCUBA 20mJy
SMA/Spitzer
HST
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Blain02
20mJy at 350 GHz

• Dusty starbursts may dominate cosmic SFR density
  at zgt2 (submm gal)?
• Formation of large elliptical galaxies?

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ALMA Deep field normal galaxies at high z

• Detect current submm gal in seconds!
• ALMA deep survey 3days, 0.1 mJy (5s), 4
• HST few 1000 Gal, most at zlt1.5
• ALMA few 100 Gal, most at zgt1.5
• Parallel spectroscopic surveys, 100 and 200 GHz
  CO/other lines in majority of sources
• Redshifts, dust, gas masses
• High res. images of gas dynamics, star formation

HST
z lt 1.5
z gt 1.5
ALMA
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Molecular gas in forming galaxies fuel for star
formation

• SF efficiency star formation rate per unit gas
  mass, increases with SFR, or
• Gas depletion timescale Mgas/SFR decrease with
  SFR
• Integrated Kennicutt-Schmidt law

1e3 Mo/yr
FIR
Index1
1e11 Mo
Index1.5
L(CO)
FIR 1e10 Lo/yr gt SFReff 3e-9 Mo/yr/Mo,
td 3e8yr FIR 1e13 Lo/yr gt SFReff 9e-8
Mo/yr/Mo, td 1e7yr
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Molecular gas in forming galaxies fuel for star
formation
Current zgt2 sources submm galaxies and QSO
hosts M(H2) gt 1e10 Mo
FIR
L(CO)
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Molecular gas in forming galaxies fuel for star
formation
Current zgt2 sources submm galaxies and QSO
hosts M(H2) gt 1e10 Mo
FIR
ALMA at zgt2 Milkyway-mass galaxies. M(H2) 1e9
Mo Line 0.1mJy in 1hr at 230GHz
L(CO)
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• Fine structure lines CII 158um detected at
  z6.4
• Dominant ISM gas cooling line, from with PDRs
  associated with star forming clouds
• SDSS QSO J11485251, LFIR 1e13 Lo
• zgt4 FS lines redshift to mm bands

30m 256GHz Maiolino etal
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CII -- the good and the bad

• CII/FIR decreases rapidly with LFIR (lower
  heating efficiency due to charged dust grains?)
  gt luminous starbursts are still difficult to
  detect in C
• Normal star forming galaxies (eg. LAEs) are not
  much harder to detect!

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CII -- the good and the bad

• CII/FIR decreases rapidly with LFIR (lower
  heating efficiency due to charged dust grains?)
  gt luminous starbursts are still difficult to
  detect in C
• Normal star forming galaxies (eg. LAEs) are not
  much harder to detect!

Current zgt2
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CII -- the good and the bad
ALMA zgt2

• CII/FIR decreases rapidly with LFIR (lower
  heating efficiency due to charged dust grains?)
  gt luminous starbursts are still difficult to
  detect in C
• Normal star forming galaxies (eg. LAEs) are not
  much harder to detect!

Current zgt2
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ALMA into reionization

• Spectral simulation of J11485251
• Detect dust emission in 1sec (5?) at 250 GHz
• Detect CII in minutes
• Detect multiple lines, molecules per band gt
  detailed astrochemistry
• Image dust and gas at sub-kpc resolution gas
  dynamics

CO
HCO
HCN
CCH
Massive galaxy formation at extreme redshift
(HyLIGRs) SFR gt 1000 Mo/yr Rare phenomenon
SDSS zgt6 QSOs 100 over whole sky!
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Median stacking of 6500 U-dropouts (z3) from
Cosmos field

• SFR(radio) 73 Mo/yr
• SFR(UV) 14 Mo/yr (w/o dust correction)
• UV dust attenuation factor for LBGs 5.2 /-
  1.2
• EVLA will detect synchrotron from individual LBGs
  in 10hr with FoV 30arcmin
• ALMA will detect dust, CO, CII in 1 hr
  (although smaller FoV 20arcsec)

VLA 1.4GHz S1.4 0.9 /- 0.21 uJy
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The ALMA revolution spectral lines
cm telescopes low order molecular lines
(sub)mm high order molecular lines fine
structure lines
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The ALMA revolution continuum A Panchromatic
view of galaxy formation
Arp 220 vs z
ALMA reveals the cool universe dust and gas, the
fundamental fuel for star formation
cm Star formation, AGN
(sub)mm Dust, molecular gas
Near-IR Stars, ionized gas, AGN
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The Sun never sets on ALMA
North American ALMA Science Center, Cville
ESO Headquarters
ALMA
NAOJ Japan
Joint ALMA Observatory, Santiago
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ALMA Site
ALMA
Paranal
Santiago
San Pedro Mission
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ALMA Sites
To AOS (43km)
OSF Site (15km)
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Operations Support Facility, Dec 07
Visitors quarters
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First production antennas at OSF in Chile
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Chajnantor Plateau looking north
V. Licancabur
Cº Chajnantor
Pampa La Bola
AOS TB
Center of Array
Currently 8 astronomical facilities operating or
planned
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APEX
AOS
array center
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AOS Technical Building
AOS Technical Building March 2007
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• Demanding ALMA antenna specifications
• Surface accuracy (25 µm)
• Absolute and offset pointing accuracy (2 arcsec
  absolute, 0.6 arcsec offset)
• Fast switching (1.5 deg sky in 1.5 sec)
• To validate these specifications three prototype
  antennas built evaluated at ATF (VLA site) --
  all passed, now under construction

Mitsubishi antenna
Vertex antenna
AEC antenna
12-m, Carbon Fiber Support Structure
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(No Transcript)
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Front EndAll modular/cartridge designAll
meeting, or exceeding spec pushing quantum noise
limit
Band 6 lab measurements
Band 9 cartridge
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Correlator Quadrant 1 (of 4)

• Well ahead of schedule.
• 3Tb/s input date rate (8GHz x 3bit x 2pol x
  64ant)
• Complete correlator contains 2912 printed
  circuit boards and 5200 interface cables there
  are more than 20 million solder joints.
• Quadrants are being stored at AOS as they are
  completed

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ALMA dynamic first fringes -- ATF, Socorro NM
Mercury 90 GHz December 2007-- Using all ALMA
electronics
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• NAASC Fully incorporated into telescope
  operations
• Chile Astronomer-on-Duty (AoD)
• Data quality assurance
• Commissioning and science verification
• Maintain and repair hardware and software
  delivered during construction

• NAASC North American portal to ALMA
• User assistance and documentation for proposals,
  scheduling, reduction
• Assist JAO in the Proposal Review Process
• Distribute pipeline processed images support
  archival research
• One-on-one expert assistance, including
  large/special projects
• RD new algorithms for calibration, imaging,
  and scientific analysis tools improved Rx,
  LO/IF
• Goal Easy access and use for all astronomers

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NAASC Science Education and Outreach

• Community development and involvement
• Scientific Workshops
• Visiting Scientists
• mm astronomy courses and summer schools
• ALMA EPO
• Help train the next generation
• 1 ALMA post-doc per year (for 3 yrs)
• 2 pre-docs per year
• Proportional support of NRAO Jansky Fellowship
  program (4 per 3 years)
• Advocate for User Grants program (6M/yr)
• 2500/hr for U.S. astronomers
• http//www.cv.nrao.edu/naasc/admin.shtml

NAASC Workshop Oct, 2008 Massive Star Formation
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• 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 (CVille)
  gearing up for science commissioning and
  operations (successful international operations
  review Feb 2007)
• Cost to complete, including ALMA-J (then-yr)
  US1.2 Billion
• 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
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END
ESO
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Higher Density Tracers HCN, CN, HCO
HCO 1-0
HCN 1-0

• Cloverleaf (z2.56) SgrB2 of high z galaxies
• Lines 5-10x fainter than CO
• High dipole moment gt high density gas ncr gt 1e4
  cm-3 dense gas directly associated with active
  star formation (GMCs)
• vs. CO, which traces gas with densities down to
  a few hundred cm-3

200uJy
250uJy
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HCN Dense gas directly associated with star
forming clouds

• FIR -- HCN linear relation from GMCs to HyLIRGs
• SFR per unit dense gas mass constant in all
  galaxies
• Conclusions
• CO traces all mol. gas
• HCN traces dense gas gt Counting star forming
  clouds
• dense/total gas increases with SFR
• ALMA is needed to push to normal galaxies at
  high redshift

Index 1
Gao , Wu
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ALMA Pushing to normal galaxies during
reionization, eg. z5.7 Ly? galaxies in COSMOS
NB850nm
Murayama et al. 07

• SUBARU Ly??????????? 10 Mo/yr
• Galaxies responsible for reionization?
• 100 deg-2 in ?z 5.7 /- 0.05
• MAMBO ltS250gt lt 2mJy gt SFRlt300
• VLA ltS1.4gt lt 2.5uJy gt SFRlt125
• ALMA - Detect dust (20uJy at 250GHz) in 3 hours
• Determine redshifts for dusty galaxies from mm
  spectroscopy

VLA Stacking analysis
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BzK Galaxies at z1.5 extremely gas rich
galaxies without extreme star formation (low SF
efficiency)

• M(H2) 1e11 Mo gt easily detected in CO searches
• FIR lt 1e12 Lo gt not seen in submm surveys
• 30x more numerous than submm galaxies

Daddi et al. 2007
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• Computing
• The fundamental output of the CIPT will be a 2M
  SLOC end to end software system running on over
  200 computers on 4 continents.
• Difficult distributed development software
  engineering practices, travel

• Using CASA as the offline system
• Completed successful CASA alpha test in March
  2007
• CASA beta release (to user community) Sept 2007
• Being used for AIVC