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Contact Information

  • 2007-11-21 14:30 UT Please check your local time; it may have changed!
  • Duration: 1 hr
  • USA Toll Free Number: 877-874-1919
  • Toll Number: +1-203-320-9891
  • Passcode: 185064
  • Leader: Al Wootten
  • Attendees: Wootten, Hogerheijde, Testi, Zwaan, Leurini, Nikolic, Hunter, Mangum, Brogan, Remijan, Reid, Emerson, Campo, Hills, Nyman, Morita, Wilson, Myers


  1. Old Business The enhanced Agenda from last meeting is available. Science IPT notes from last month's telecon are in the agenda in blue. See status report attachment please for additional photos.

A Virtual Reality (Quicktime) tour of the OSF under construction on 31 Oct 2007. From right to left: Beasley showing Rykaczewski the AEM area; Transporter shelter; Licancabur; Building; OSF Warehouse (lower level); OSF Offices; Foreground, lower level--pads for antennas under construction

VertexRSINo1 The VertexRSI antenna number one in front of the Site Erection Facility 2007 October 31.

Melco No 1 The Melco antenna number one on 2007 October 31, taking a break from holography. See other images and animations. See other images.
  1. New Business--Project news/updates (Hills, Peck)
  2. Current Science IPT Schedule. Current Operations Schedule. very high level summary Schematic IPS. (2007 October 31)
  3. 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 (Hills/Wootten):
      • Cross-polarization specifications (No 173): Several Receiver Construction groups are having trouble meeting the cross-pol requirement, which is set at -20dB. Requests are being made to lower this to -17 or -16dB. In some cases the cause of the some of the cross-pol is intrinsic to the design but only for Band 9 is theoretical value worse than -20dB. The rest of it must be coming from other sources, such as the IR filters. The underlying Science requirement is to achieve 30dB after calibration. So the question is how much harder will it be to achieve this if the raw data has only -17dB purity instead of -20dB?
      • Hot and Ambient Load requirements (No 183): A new set of requirements has been proposed that sets lower levels on the allowed backscatter, in order to keep down standing wave effects, but only requires the hot load to work for Bands 3 and above. Analysis shows that that for Bands 1 and 2 the required calibration accuracy can be achieved with only an ambient load.
      • RF membrane: Recent investigations have confirmed that the loss in performance caused by the Goretex membrane is much higher than had apparently been expected. The problem is that with a thickness of half a millimetre and a refractive index of ~1.14 there are peaks in the reflection at ~133, 400, 666GHz, etc. Most of this reflection is terminated on ambient temperature sources in the "widget" space in front of the receiver. For bands 2, 3 and 4 where the noise temperatures are expected to be low, the loss of sensitivity may be as high as 7%. Hills is working with Ricardo Finger on investigations of alternative materials. Much more on this topic can be found at RF Membrane Wiki.
    • ATF:
      • Summary (Peck)
      • Goals: (1) Get software working (2) Training personnel and developing procedures
      • Priorities:
        • (1) Test (total power) functionality needed for antenna acceptance testing
        • (2) Dynamic Interferometry (software control of fringe rotation and delay)
        • (3) Write data in ALMA format
        • (4) Perform Calibration measurements such as Pointing Interferometrically
        • (5) Fast Switching
      • Current total power functionality available includes (not necessarily with ALMA/CIPT software):
        • Optical pointing (Acceptance 2007-May-24; much work still needed)
        • holography (Acceptance 2007-May-31; still needs work)
        • focus (2007-July-2?; still marginal but workable)
        • radiometric continuum pointing (2007-Sep-12; still needs much work)
      • 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 Simple Phase trajectory is being established and verified. Only the FLOOG is being used, no 2nd LO.
Week Event
Nov 19
Peck, Nyman exercising dynamic interferometry, solving for residual fringe rate
Nov 26
Peck, Hales: exercising dynamic interferometry, solving for residual fringe rate
Dec 2
Hales: Pointing following expected antenna work?
Dec 9
Hales, Remijan, Indebetouw: More interferometry exercises. Support data output work
Dec 16
Remijan, Indebetouw: More interferometry exercises. Support for data output work

| Dec 23 | Christmas/New Year break; no Sci IPT staffing
  • OSF
Week Event
Jan ??
VxRSI Holography

  1. Astronomer Outreach: NRAO Newsletter New ESO, New NRAO Newsletter NAOJ News. NRAO ALMA Calendar
  2. ARC News.
  3. Group Activities (all)
  4. Next meeting is on December 19th (14:30 UT). January 16th for the following month.

Emerson/Laing/Vila-Vilaro -- Instrument Scientists

  • PSI at the ATF: Schedule, Daily Logs
  • Remijan's site to submit updates/logs/checklists for most of the procedures necessary to operate and get up to speed on the current status of the software and control systems at the ATF can be found at: ATF Updates. Please use this system at the ATF so the next member of the science IPT who arrives on site has the most recent version of the checklists and updates. Please also enter something in the daily log section! If you want a new database created for new checklists that does not fall under Science IPT Notes, contact Remijan with the title of the checklist you desire and he will add it to the site.

Holdaway, Conway -- Configuration Group

  • 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). We continue to assess configuration performance.
  • New <4km Configuration approved Passed CCB.
  • Proposed ACA Configuration approved.
  • ArrayCenter shows photos of the region of the center of the Array.

Jeff Mangum -- Calibration

  • 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 (2007-11-14).
  • Release 5.0 being integrated, will woon be installed at the ATF. This includes new ASDM version
  • Work on filler into CASA for that ASDM version (expected in Dec).
  • Progresses made in finalizing common binary data format between ALMA and EVLA.
  • Software testing at ATF: single dish and simple interferometry. Fringes regularly obtained but no ASDM data yet (sometime in December?).
  • Regular testing of subsystems and integrated system at the ATF.(see SSR link above)

Michiel Hogerheijde -- DRSP

  • All DRSP2.0 projects have been reviewed, and responses of the authors have been collected. The findings were discussed at the ESAC and ASAC face-to-face meetings in April and May, and are summarized below.
    • Out of 149 projects from 53 authors, 42 were revised w.r.t. DRSP 1.0; 18 are entirely new; and the reminder (85) was either unchanged or no response was received (but still reviewed).
    • The distribution over science areas has not changed much.
    • Integration times were tweaked here and there, but the main uncertainty lies in including realistic overheads.
    • Quite a few projects requested cross-correlation of the 7m ACA antennas with the baseline-ALMA 12m antennas. While for some projects this is indeed essential, for most this was used only to increase the sensitivity. In terms of scheduling and operations this may be undesirable, and this needs to be reflected in the DRSP to make sure the 7m*12m is not 'overbooked'. *H
    • Once the final DRSP 2.0 projects with the authors' response included and reasoned 7m*12m requests included are added to the web site, the password protection on the latter will be removed. The details of the DRSP 2.0 will also be entered into a spreadsheet.
    • OT is almost ready to try deriving observing modes and overheads using DRSP 2.0 projects.
  • Hogerheijde presentation on DRSP2.0 to the ASAC

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

  • Commissioning and Science Verification

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

  • CASA Simulator Report
    • The Library of standard ALMA images for simulation is available.
    • Dirty beam images have been made for all of the ALMA configurations, for both snapshots and 4h exposures at a variety of declinations.
    • 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

L.-A. Nyman -- Site Characterization

  • 21 September Radford restarted the NRAO interferometer at Chajnantor. It was a simple software glitch; a scratch directory had overflowed. His immediate goal is to see if there's a correlation between the interferometer phase fluctuations and the sky noise fluctuation seen with the Aztec and Laboca bolometer arrays.
  • Radford notes that the current phase monitoring interferometer baseline is east-west. In retrospect, it would make more sense to align it perpendicular to the direction of the satellite, about 335 deg (NW) - 155 deg (SE). Comments?
  • OSF Weather Station link.
  • In December 2006 JeffMangum submitted weather station instrumentation (RH, P, T, and wind) RFQ documentation to NRAO procurement system. After having reviewed information received from bidders and consulted with Calibration Group (see CalAncillary for discussion), on 2007/03/21 JeffMangum submitted purchase information to RobertLaing for procurement. Leonardo Testi received first set of weather measurement devices at ESO in late October. Will assemble unit at ESO for testing.
  • ICD submitted for AOS site locations discussed during August meeting. A few kinks under discussion with computing and site include power distribution (440V needs transformer) and fiber lighting (only done when antenna occupies station).The battery bank ESO2 now supplying power at the AOS will be moved to the guardhouse at the intersection of CH23 and the ALMA Road. Ulf Kaberger to implement; presumed done now but no confirmation has been received. Possible changes: phase monitoring interferometer baseline (should be 300m, not 100m) and orientation?

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

Discussion of pipeline heuristics and how science advice may be incorporated.

Science Corner:

The Proceedings of the First NAASC ALMA Workshop, From Z-Machines to ALMA: (Sub)Millimeter Spectroscopy of Galaxies, has been published as Volume number 375 of the Astronomical Society of the Pacific Conference Series. A. Baker, J. Glenn, A. I. Harris, J. Mangum and Min S. Yun edited the volume.


Official JAO Calendar

ALMA Events of Interest

(see also Al's ALMA Biweekly Calendar)
Day Date Time Event location details
Oct 30-31
all day
ALMA Board Meeting
all day
Nov 7
Nov 13-15
all day
ALMA Preproduction Review
Nov 15
Calibration Group
Nov 21

Upcoming Meetings

North American URSI meeting Jan 3-6 2008, Boulder

AAS meeting Jan 7-11 2008, Austin, Tx (NRAO/ALMA booth)

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

See also NAASC listing

-- AlWootten - 16 Nov 2007

This topic: ALMA > WebHome > AlmaSci > AlmImcal > MonthlyMeetings > 21Nov07Agenda
Topic revision: 2010-08-02, ToddHunter
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