Draft Agenda for ASAC Telecon May 8, 2000 2100 UT
Conference Date: MAY-08-2000 (Monday)
Conference Time: 2300 CET; 2100 UT; 1700 EDT; 1500 MDT ; 1400 PDT; 1700 Chile; 0600 (Japan 9 May )
Conference Duration: 1 hr
Service Level: STANDARD
Call Type: MEET ME
Passcode is: ALMA
Conference Leader is Welch
From the US please dial: 888-603-7034
From International locations please dial: +1-415-228-4641
Wootten will be unable to attend. Menten may have difficulty.
0. News. See ASAC WWW page for past minutes, etc. A New Project Book is available for ALMA. (Guilloteau or Emerson?)
1. Review reviews of Science Software Requirement Document (Gurwell)
2. Construction Cost Agreement. See Letter to Dr. Eisenstein . ((Guilloteau or Emerson?)
3. Receiver Meeting Minutes are available (Apr2000). (van Dishoeck or Blake?)
4. Nutator Plans. (Welch or Walmsley?)
5. WVR: See Japanese SPIE report. (Richer or Wilson?)
6. Upcoming Reviews: Test Interferometer plans, Antenna PDR (June 20-23). (Emerson, Welch or Walmsley?)
ALMA Science Advisory Committee
Teleconference, 8 May 2000
Draft Minutes
Participants: Bachiller, Brown, Crutcher, Evans, Fukui, Gurwell, Hasegawa, Nakai, Richer, Shaver, van Dishoeck, Walmsley, Welch (acting chair), Wilson, Yun
The draft agenda was accepted as proposed.
1. News
R. Brown summarized recent developments since the last telecon. In particular, the ACC had held its first telecon earlier in the day (8 May), and the following points relevant to the ASAC were noted: a) A Japanese membership of five on the ASAC was approved. b) The ASAC will be expected to judge the scientific benefits to the overall project that will result from various options for Japanese contributions. An updated list of possible enhancements will be provided to the ASAC by the AEC. It is hoped that Japan will be able to commit to the project by the end of the year. c) Optimization of the baseline project within the new cost envelope: this is an ongoing process requiring ASAC input. J. Richer stressed that the ASAC should be sure that the new definition of the baseline project is the optimal one for scientific reasons. It was agreed that this optimization should be a major discussion item for one of the next telecons.
2. Science Software Requirements
M. Gurwell summarized recent discussions concerning Science Software requirements. The basis was ALMA memo 293 dated 7 March, which has subsequently been reviewed in detail. A strawman description of the needs for the array has been outlined. There are four main modes of operation: (1) technical interface, (2) manual mode, (3) interactive mode (to be normally used by the operators), (4) dynamic scheduling mode.
Much of the discussion concerns how dynamic scheduling is to be implemented, and what pipeline possibilities should be provided (eg. just for observing decisions, or full data reduction?). There was a concern that the plans can become too grandiose. It was suggested that the pipeline should not be in the critical path, and pipeline operations be separated from observations. On the other hand it is very important that the science products of the array be accessible to the wider community, not just experts. The experience of other groups working with dynamic scheduling concepts would be a valuable input. It was generally felt that guidelines are needed here to focus the development.
3. Construction Cost Agreement
R. Brown reported that the ASAC letter of 18 April 2000 to the ACC had been very well received, and that the funding developments are now moving along extremely well.
4. Receiver Meeting Review
E. van Dishoeck reviewed recent developments. Discussions have focussed on optics and dewar design, and there have been some significant changes since the Leiden ASAC meeting. A number of other issues include DSB vs. SSB, polarization specs, total power stability, and aspects of band 3. There is a concern about the 1% calibration spec, and clarification is needed as to whether this is absolute or relative. A number of questions are being prepared by the receiver group to be addressed to the ASAC by 20 May, and the ASAC response will be required by 9 June.
5. Nutator Plans
J. Welch commented on recent developments. Whether all, few, or no antennas of the array will have to be outfitted with nutators is an issue to be settled. Nutators will be tested on the prototype antennas, and tests will also be made to determine whether OTF can be done without nutators. Comments on the specific nutator design should go to S. Radford. Concern was expressed about polarization mapping with nutators, and the relatively small (1.5') throw. R. Brown said that this effort has been temporarily suspended owing to funding limitations, and that the division of effort (US/Europe) is presently under discussion.
Items 6 (WVR) and 7 (upcoming reviews) were postponed to the next telecon because of lack of time.
8. Next Meeting
The next ASAC telecon is on Monday 12th June at 21:00 UT.
The next face-to-face meeting will be held in Berkeley in September. Possible dates will be proposed by K. Menten and J. Welch. *******************************************************************