eSMA: the SMAJCMTCSO array David J' Wilner HarvardSmithsonian CfA - PowerPoint PPT Presentation
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eSMA: the SMAJCMTCSO array David J' Wilner HarvardSmithsonian CfA
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The SMA is a pathfinding instrument comprised of eight 6 meter ... Subcompact. Compact. Extended. Very extended. Field of View/Resolution. Spatial Resolution ... – PowerPoint PPT presentation
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Title: eSMA: the SMAJCMTCSO array David J' Wilner HarvardSmithsonian CfA
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eSMA the SMA-JCMT-CSO arrayDavid J.
Wilner(Harvard-Smithsonian CfA)
- HIA (Sub)Millimeter Observing Techniques Summer
School - August 14-17, 2006
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What is the SMA?
- The SMA is a pathfinding instrument comprised of
eight 6 meter antennas on Mauna Kea, HI, designed
for high spatial and spectral resolution imaging
in submillimeter atmospheric windows. - The SMA is now being used to study Solar System
bodies, protoplanetary disks, star forming
regions, evolved star envelopes, the Galactic
Center, nearby galaxies, and ultraluminous
galaxies at cosmological distances. - The SMA is a collaborative project of the
Smithsonian Astrophysical Observatory, part of
the Harvard-Smithsonian Center for Astrophysics,
and the Academia Sinica Institute of Astronomy
and Astrophysics (Taiwan)
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SMA and Pupuliahu
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Historical Perspective
- 1984 SAO Study
- (1992-1998 CSO-JCMT)
- 1994 OSDA U. Hawaii
- 1996 ASIAA expansion
- 2 antennas (to 28 baselines)
- 1999-2003 antennas deployed to Mauna Kea
- 2001 JCMT MOU (aim 2005)
- 2004 first SMA science
- 2006 gt50 refereed papers
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SMA Specifications (and why)
Specifications
- Antennas 8 antennas of 6 m diameter, 12
?m rms surface - cost imaging speed
collecting area (JCMT) - Configurations 24 pads in four rings
- baseline lengths 8 - 508 m,
- subarcsecond resolution,
best 0.1 - Receivers max 8 per antenna 2
simultaneously - full frequency coverage of
atmospheric windows - dual polarization high
low for calibration - 177-256 GHz (8 in
operation) - 256-360 GHz (8 in
operation) - 320-420 GHz (start 2006),
420-520 GHz (future?) - 600-720 GHz (8 in
operation) - 780-920 GHz (future?)
- Correlator 2 GHz bandwidth, up to 25 kHz
resolution - sensitivity, span/resolve
extragalactic/galactic lines
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Receiver Bands/Atmosphere
460 GHz
230 GHz
345 GHz
690 GHz
805 GHz
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Antenna Stations
- 4 Nested Rings (Keto 1997)
- 4 Configurations
- Subcompact
- Compact
- Extended
- Very extended
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Field of View/Resolution
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SMA Correlator
LSB 2 GHz 24x82 MHz
USB 2 GHz
24x82MHz
10 GHz
e.g. Orion-KL, Beuther et al.
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Spectral Coverage/Resolution
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Observing Information
- SMA partner fractions CfAASIAAIfA 721513
- 20 of CfA time available to PIs from
worldwide astronomical community w/CfA
collaboration - proposal deadlines on 6 month cycle
(March/September) - next deadline Sep 7, 2006 (for Nov-Apr)
- last deadline 80 proposals, 8/31 external PI
proposals rated A - multiple antenna configurations available
- dynamic queue scheduling according to weather
- RTDC archive, data in public domain after 15
months - Calibration and Imaging
- MIR (OVRO)/Miriad and Miriad/AIPS
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http//sma1.sma.hawaii.edu
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http//sma1.sma.hawaii.edu
- SMA Observer Center
- Current Call for Proposals
- Updated Status of Array Technical Capabilities
- Proposal Submission Facility
- Tools
- Beam Calculator/Sensitivity Estimator
- Passband Visualization
- Submillimeter Calibrator List and Flux History
- Link to RTDC Archive Search
One Stop Shopping for All Your SMA Needs
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Beam Calculator/Sensitivity Estimator
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Beam Calculator/Sensitivity Estimator
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Passband Visualizer
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Submillimeter Calibrator List
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What is the eSMA?
- the eSMA is a collaboration between the SMA, the
JCMT, and the CSO, to join all three
observatories into a single interferometer array - will operate part-time in 345 GHz atmospheric
window
JCMT 15m CSO 10.4m
SMA 8x6m
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Why? I. More Sensitivity
- JCMT and CSO double the array collecting area
- for each baseline
- point source sensitivity
- full track, dual pol, 345 GHz, pwv 1mm, dec 30
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Why? II. More Resolution
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Why? II. More Resolution
- JCMT pad 25
- CSO pad 26
- longest baseline 508 ? 781 m
- uniform weight beam _at_345 GHz 0.31
x 0.18 (49o)
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eSMA Testing
- 2005 May SMA IF/LO equipment to JCMT
- 2005 Jul first fringes SMA-JCMT (3C454.3)
- 2005 Sep SMA IF/LO equipment to CSO
- 2005 Oct first fringes with SMA-JCMT-CSO
- 2005 Dec attempt to measure baselines
- 2006 new receivers (to be) deployed
- SMA 320-420 GHz, enables 2 pol. 320-355 GHz
- JCMT refurbish RxW, 345 band, 2 pol, IF 4-6 GHz
- CSO new 280-420 GHz, 1() pol, IF 4-6 GHz
- 2007? science observations
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First Fringes SMA-JCMT (267 GHz)
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SMA-JCMT Orion-KL Spectra
- LSB (221-222 GHz) USB (230-231 GHz)
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A few eSMA Issues
- different sky rotation of polarization
- baseline non-intersection of axes terms
- interfaces for SMA control of JCMT and CSO
- JCMT and CSO phase stable? (slew, focus, )
- correlator modes
- 8 SMA CSO JCMT 45 baselines (1 pol)
- 6 SMA CSO JCMT 28 baselines (2 pol)
- eSMA baselines are all long (subarcec)
- implications for SMA configuration(s)?
- politics of time allocation
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eSMA Outlook
- no insurmountable technical problems (yet)
- on track for science observations in 2007
- a lot of exciting science
- opportunities to get involved
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Key People
- SMA Director............. Ray Blundell
- Technical...................... Bob Wilson
- Operations (Hilo)....... Ant Schinckel
- ASIAA........................ Paul Ho
