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  • 2008-2-20 14:30 UT Please check your local time; it may have changed!
  • Note: C. Wilson points out line noise may be muted by pressing *6 which works thru the call center.
  • Duration: 1 hr
  • USA Toll Free Number: 877-874-1919
  • Toll Number: +1-203-320-9891
  • Passcode: 185064
  • Leader: Al Wootten
  • Attendees:


  1. Old Business The enhanced Agenda from last meeting is available. Science IPT notes from last month's telecon are attached to the bottom of the agenda.

First ALMA correlator celestial spectrum The first interferometric spectrum taken with ALMA/ATF toward Orion Hot Core in the vicinity of the CS 2-1 line. Courtesy Todd Hunter.

See other images and animations. See other images and transporters.

  1. New Business--Project news/updates (Hills, Peck)
  2. Current Schedule.

  1. Directories

Science IPT Group Activity Reports

Please include your Group Activity Report here (How to Enter Your Report), or email it to AlWootten

Project Scientists

  1. Science IPT -
    • Change Control Board items, other technical concerns (Hills)
      • Polarization. CRE 164 to relax the requirement for Band 9 is still pending. Following a recent telecon on this it appears that there is not a great deal of scope for improvement in this case. For some of the other bands, however there has been some progress in finding ways by which the polarization purity may be improved. The question I would like to raise now is whether we should resurrect the idea of injecting a coherent signal of known polarization into each antenna as an aid to calibration.
      • LO Phase lock bandwidth. CRE 179 proposes reducing this which should reduce phase noise at the highest frequencies but loose a little efficiency from the lag when phase switching.
      • Acceleration of the 7m ACA antennas. CRE 184 proposes reducing the maximum accelerations and demonstrates that the loss of observing efficiency will be small.
      • Here Draft Front End Pointing CRE is a first version of a change request aimed at ensuring that the any pointing errors arising due to deflections in the front end are small. Differential movements between the receivers would be particularly damaging to offset pointing.
    • ATF: (Peck)
      • Summary. Latest report is ATF Jan 08
      • Log of 8-13 February observations. Recent data to investigate nature of saw-tooth phase pattern seen when including antenna heights into the delay server.
      • Goals: (1) Get software working (2) Training personnel and developing procedures
      • Spectral-line pointing needs to be available in Q1 2008 for single dish testing in Chile.
      • The current schedule is below. Please let Alison and Debra know if anyone has any issues with this. During the current period foci of interest include further understanding of the behavior of the Line Length Corrector, to measure the baseline correctly and to begin interferometric pointing.
Week Event
Feb 17
Peck, Brogan, Remijan
Feb 24
Peck, Remijan, Martin
Mar 2
Remijan, Reid, Nyman
Mar 9

  • OSF
Week Event
Feb 15
Emerson VxRSI antenna contractor handover testing begins 4 Feb

  1. Next meeting is on March 19th (14:30 UT). April 16th for the following month.
  2. Astronomer Outreach: ESO Newsletter New ESO Messenger with Antenna article, New ESO ALMA News New NRAO Newsletter appearing soon. NAOJ News. NRAO ALMA Calendar

Emerson/Laing/Vila-Vilaro -- Instrument Scientists

  • PSI at the ATF: Schedule above; see report in attachments.

Richard Hills, Alison Peck, Robert Laing -- Commissioning and Science Verification

  • Commissioning and Science Verification

Holdaway, Conway -- Configuration Group

  • Work has begun on six foundations along Road 11 near the AOS TB. The first 6 foundations under construction are: 104,136,109,96,101,106. Three of these are along a spur in Road 11; minimum baseline there is about 100m; maximum baseline is about 1.4 km. AIV may have a requirement that the first antennas be located on pads near the building; that is not a science requirement. Our requirements for the first 6-8 antenna locations are given in an approved document by Conway, ALMA 90-02.00.00-004-A-SPE First Science Array Configurations. This was written with the 64 station design as a starting point; Wootten is reviewing it now to determine what changes are needed for a 50 station design as now approved.
  • Holdaway's description of the development of the design for the extended ALMA configurations, rev 2 for edm.
  • Eduardo Donoso and Simon Radford determined the separation between the planned ALMA antenna station A104 and the existing CBI generator plant is about 50 m. Tony Readhead and Radford agree this separation should be adequate for CBI operations and maintenance.
  • And then there were four... Array layout on the high site; weather station locations have orange dots. PDF. The Technical specifications and SOW for the IFB for the AOS Road network design have been completed. A design for road and fiber network at the high site is to be bid for construction shortly. Design of the extended array is complete; bids for antenna pad construction are out.
  • Final configuration design. We continue to assess performance - see imaging, below, and possible improvements.
  • New <4km Configuration approved Passed CCB.
  • Proposed ACA Configuration approved.
  • ArrayCenter shows photos of the region of the center of the Array.
  • has been created as a repository of miscellaneous configuration evaluation items.

Steve Myers/Rob Reid (Mark Holdaway)-- Imaging

  • A set of ALMA PSFs with varying amounts of robust weighting has been made and summarized in weighting.html. It will be useful for determining how much Briggs weighting to use when, but the most immediately interesting result is that it should be possible to use any resolution in the ALMA range with only a litte reweighting: . The set is being extended with tapered beams.
  • CASA Simulator Report
    • The Library of standard ALMA images for simulation is available.
    • Fidelities over 104 have been achieved for 4 hour noiseless "observations" of the M31 HII region, using deep cleans with a tightly constrained support region.
    • CASA simulation wiki with examples
    • Bojan Nikolic is using the simulator to make u-v data and maps when investigating the effects of atmospheric phase and, in the future for trying out phase-correction techniques.
  • Pointing selfcalibration for mosaics

Jeff Mangum -- Calibration

  • Response to ASAC comments
  • Pointing Design document now drafted.
  • Calibration Plan: Current version of the calibration plan and associated documents ("examples", "roadmaps", "matrices", etc.) posted. Comments welcome.
  • Calibration Examples: The "meat" of the Calibration Plan. Review of these documents nearly complete, some need updates.
  • Ancillary Calibration Devices: Documents which describe the weather station and temperature profile technical specifications have been developed. Initial purchase documentation for (P,T,RH,Ws,Wdir) measurement devices has been made by Leonardo.

Robert Lucas -- SSR

  • Latest SSR meeting (2008-2-13). Meeting with Operations.
  • Regular testing of subsystems and integrated system at the ATF.(see SSR link above). ASDMs produced at ATF.
  • ACA Correlator integration work
  • Decisions on Schema Versioning in Archive
  • ASDM Finalization started ...

Michiel Hogerheijde -- DRSP

  • No progress on including the author responses to the referee comments, the DRSP 2.0 web site continues to be password protected. If you would like access (keeping in mind that the author responses have not been added yet) use: username=review and password=chajnantor! (including the exclamation mark).

L.-A. Nyman -- Site Characterization

  • Oxygen thermal profiler
    • Radiosonde launches needed to 'teach' profiler
      • With Eduardo Donoso Wootten visited the radiosonde container, the rightmost (blue) of two containers further down the ridge from the site characterization containers on 2008 Jan 31. The container has the same combination as the primary one; the lock was only a little recalcitrant. In front of the door are three concrete blocks used for mounting the sonde tracker, which is just inside the door. This is a good idea as in the past sudden windgusts have knocked the tracker down with some damage. Behind it, below the desk on the floor is a box of sondes. I counted the topmost layer, estimating about two dozen sondes are there, Vaisala units. To their left is a large stash of meteorological balloons, at least fifty of them. The inside of the container appeared to be in good shape. A weather station still stands on a tower behind the container, though one of its guy wires seemed untaught. If additional launches are needed, we can use this stock. I propose doing this from the OSF, however, as it is operationally easier. A proposal to move this facility should be part of the plan to transition site characterization facilities to operations.
    • Draft Memo on Sonde launches Nikolic provided additional sonde data from the 2005 August campaign led by Stirling, Otarola and Rivera.
  • OSF Weather Station link.

Remijan, Markwick-Kemper -- ALMA Working Group on Spectral Line Frequencies

Science Corner:

* Please note that: Science with the Atacama Large Millimeter Array: A New Era for Astrophysics Volume 313, Numbers 1-3 / January, 2008, the Proceedings of the Nov 2006 ALMA Conference in Madrid, has been published by Astrophysics and Space Science, and is available online. Thanks to the organizers of the conference, to the authors and to the editors for bringing out this compendium of papers describing some aspects of the transformative science we expect ALMA to undertake. We're all anticipating smooth completion of the instrument over the next few years; just ten days ago the ALMA prototype system at the ALMA test facility produced its first interferometric spectrum. Working together, we'll be producing solid science soon.


Official JAO Calendar

ALMA Events of Interest

(see also Al's ALMA Biweekly Calendar)
Day Date Time Event location details
Jan 15
ESAC face-to-face meeting
Jan 18
ANASAC telecon
Jan 23-24
Nutator CDR
Feb 1-2
ASAC face-to-face
Feb 7-8

Upcoming Meetings

IAU Symposium 251 Organic Matter in Space Feb 18-22, Hong Kong

The Cosmic Agitator - Magnetic Fields in the Galaxy 2008 March 26-29 Lexington.

29th URSI General AssemblyChicago, Illinois, USA, 9-16 August 2008. Abstracts due 2008 Jan 31

See also NAASC listing

-- AlWootten - 18 Feb 2008
Topic revision: r17 - 2010-08-02, ToddHunter
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