The Atacama Large Millimeter Array: Imaging the Cold Universe

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The Atacama Large Millimeter Array Imaging the
Cold Universe

• C. Carilli (NRAO)
• April 2, 2007

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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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.
• 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 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 Broad Band Spectroscopy 2pol x
8GHz x 16k ch Birth of stars physics/chemistry
of star formation 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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Giant Steps V Site quality
t 0.5 at 0.9 THz
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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 res.
Williams et al.
HST
Wolf Simulation of nearby PP disk (eg. TW Hy)
5AU 0.1
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Magic of (sub)mm cosmology distance
independent method of studying objects in
universe from z0.8 to 10 L_FIR 4e12 x
S250(mJy) L_sun SFR 1e3 x S250 M_sun/yr
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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Pushing into reionization QSO 114852 at z6.4

• Highest redshift quasar known (tuniv 0.87Gyr)
• Lbol 1e14 Lo
• Black hole 3 x 109 Mo (Willot etal.)
• Gunn Peterson trough (Fan etal.)

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SDSS J11485251 Dust and molecular gas into
cosmic reionization
J1148 VLA CO 3-2
50K
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Elvis SED
Radio-FIR correlation
Giant cloud (5.5kpc) of gas and dust 7e8 Mo in
dust 2e10 Mo in gas

• Hyper luminous IR galaxy (FIR1e13 Lo)
• Follows Radio-FIR correlation SFR 3000
  Mo/yr ?
• Coeval formation of SMBH/Galaxy?

• Early enrichment of heavy elements (zsf gt 8)
• Dust formation by massive stars?

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CII 158um PDR cooling line detected at z6.4
PdBI Walter et al.
30m 256GHz Maiolino etal
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0.3

• Size 0.5 ( 2.5kpc)
• SFR 6.5e-6 LCII 3000 Mo/yr
• Enriched ISM on kpc scales

• LCII 4x109 Lo
• LCII/LFIR 3x10-4 ULIRG

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• SDSS J09272001 z5.8
• FIR-luminous QSO host submm galaxy companion
  
• Separation 87kpc Merging/interacting
  galaxies?

SharkII CSO 850 GHz rms5mJy
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• Rare objects 100 SDSS z6 QSOs on entire sky
• Integration times hours to days on HLIRGs

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ALMA into reionization

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

CO
HCO
HCN
CCH
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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) in 3 hours
• Determine redshifts for dusty galaxies from mm
  spectroscopy

VLA Stacking analysis
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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
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ALMA Sites
To AOS (43km)
OSF Site (15km)
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Vertex Site Erection Facility Mar 2007
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Lascar April 2006 October
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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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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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First Vertex Production Antenna Heading to Chile
March 2007
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Front EndAll modular/cartridge designAll
meeting, or exceeding spec
Band 6 lab measurements
Band 9 cartridge
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FE 1 (4 cartridges) Mar07
Band 3
Band 7
Band 9
Band 6
Receiver integration (4 bands) at CDL in Cville
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Correlator Quadrant 1 (of 4)

• Well ahead of schedule.
• Complete correlator contains 2912 printed
  circuit boards and 5200 interface cables there
  are more than 20 million solder joints.
• Jan 2007 second quadrant in production new
  test correlator

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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

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ALMA first fringes (Emerson ) ATF, Socorro NM
Saturn 90 GHz March 2, 2007 Used all ALMA
electronics and software
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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 Portal for NA Astronomers to ALMA
• Test and provide user friendly web-based
  documentation for Proposal tool, Observing tool,
  Post-processing and data analysis
• Assist JAO in the Proposal Review Process
• Verify and correct observing scheduling blocks
• Distribution of data and processed images
  support archive research
• One-on-one expert assistance with observation
  preparation and post-processing user support,
  including large/special projects
• Research/develop new approaches/algorithms for
  calibration, imaging, and scientific analysis
  tools, including spectral line database

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Spectral Line catalogs and tools needed to deal
with tremendous spectral complexity
Lines visible in Band 9 (CSO)

• NAASC initiative (Remijan Markwith-Kemper)
• Unified spectral line database reconcile
  differences
• Incorporate into ALMA observing tool
• Long-term maintenance by NAASC

Schilke et al. (2001)
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NAASC Science Education and Outreach -- Full
service

• 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)

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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)
  US1.3 Billion
• Timeline
• Q1 2007 First fringes at ATF (Socorro)
• Q1 2009 Three antenna array at AOS
• Q1 2010 First call for (early science)
  proposals
• Q3 2010 Start early science (16 antennas)
• Q4 2012 Full operations

ESO
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END
ESO
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Giant Steps II Sensitivity
Index1.7
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Giant Steps II Sensitivity
Current zgt2
5e10 M_sun
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Giant Steps II Sensitivity
Current zgt2
ALMA zgt2
Line 0.1mJy in 1hr at 230GHz
5e10 M_sun
1e9 M_sun
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ALMA Transporter
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ALMA Transporter FDR January 2007
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Giant Steps III Image quality
CO 3-2/CSO
Optical/ESO
IR/ISO

• TBline sub-K at 0.25 arcsec res.
• TBcont mK at 0.25 arcsec res.

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ALMA Median Continuum Sensitivity(1 minute
AM1.3 75 Quartile opacities lgt1mm, 25 l lt1mm)
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Brightness Temperature Sensitivity1 min, AM 1.3,
1.5mm, 0.35 PWV, 1 km/s
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Receivers/Front Ends
ALMA Band Frequency Range Receiver noise temperature Receiver noise temperature Mixing scheme Receiver technology
ALMA Band Frequency Range TRx over 80 of the RF band TRx at any RF frequency Mixing scheme Receiver technology
1 31.3 45 GHz 17 K 28 K USB HEMT
2 67 90 GHz 30 K 50 K LSB HEMT
3 84 116 GHz 37 K 62 K 2SB SIS
4 125 169 GHz 51 K 85 K 2SB SIS
5 163 - 211 GHz 65 K 108 K 2SB SIS
6 211 275 GHz 83 K 138 K 2SB SIS
7 275 373 GHz 147 K 221 K 2SB SIS
8 385 500 GHz 98 K 147 K DSB SIS
9 602 720 GHz 175 K 263 K DSB SIS
10 787 950 GHz 230 K 345 K DSB SIS

• Dual, linear polarization channels
• Increased sensitivity
• Measurement of 4 Stokes parameters

• 183 GHz water vapour radiometer
• Used for atmospheric path length correction

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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!