1. ALMA Science Advisory Committee

Teleconference 10 January 2000

Participants: Blake, Booth, Bronfman, Cox, Crutcher, Emerson, Evans, Fukui, Guilloteau, Gurwell, Hasegawa, Ishiguru, Kawabe, Martin-Pintado, Menten, Nakai, Richer, Shaver, van Dishoeck, Walmsley, Welch, Wilson, Wootten, Yun

*** please add/correct names (were Benz, Hayashi, Scoville present?)***

Draft Minutes

  1. Charter

 

The draft charter was discussed and revisions proposed. In para I the origin and role of the ASAC will be made more explicit. The last sentence was shortened to "The ASAC will also provide communications to the wider community". Concerning frequency of meetings, the intention is that face-to-face ASAC meetings should take place before each ACC meeting, typically thrice per year. The rotation of chairperson was discussed and the draft version was agreed, with the addition "in general we expect the chair to rotate between North America and Europe". Para III(2) was revised to "Decisions will be made by simple majority. A minority report may be included…" The draft charter has been posted on the website above for any final changes.

  1. Public Outreach

 

A. Wootten mentioned that changes are currently being made, and the web address has just been changed to http://www.alma.nrao.edu/committees/ASAC/index.html.

Suggestions for improvements should go to Al or to Kate Weatherall. Brief comments were made about the aesthetics of the web site, and the need to include papers from the October science meeting (and others). On the latter point A. Wootten said that links will be provided to the conference papers, also to the full proceedings of the October meeting. J. Richer asked whether there is now a single document that gives a comprehensive and clear statement of the science case. At the moment there is not, except for the brochure from the ALMA meeting, and this is a task to be completed.

At the moment the science requirements and their origins (most recently for the MMA the results of the 1995 Tucson workshop, which could be updated to reflect the new capabilities of ALMA versus the MMA). Five reports were written following the Tucson Workshop that summarize the science goals in the following categories:

  1. Cosmology and Extragalactic
  2. Star Formation and Stellar Evolution
  3. Galactic Molecular Clouds and Astrochemistry
  4. Solar System
  5. Sun and Stellar

Submillimeter performance was sought of the MMA at this meeting. The MAC summarized scientific drivers for the submillimeter operation of the MMA in 1998:

The scientific requirements for the LSA were similarly discussed and summarized in documents

  1. Scienceat high Z or the youth of the Universe
  2. Planetary Formation or the youth of the Solar System
The arguments were summarized at a 1995 meeting in Garching, at which the motivation was written. The LSA science requirements were issued, and in the 1998 April LSA/MMA Feasibility Study explored options for combining the arrays. At a meeting in 1999 February in Tucson, the science requirements were joined and are described in the Project Book.

Most October ALMA conference articles are located at this location.

 

The draft announcement to be distributed to various newsletters was briefly discussed. Final comments and suggestions should be sent to N. Evans. K. Menten is collecting a list of relevant newsletters, and will continue to accept additions over the next week.

  1. Membership

N. Evans welcomed the new members from Japan and Chile.

  1. Leiden Meeting

E. van Dishoeck outlined plans for the ASAC face-to-face meeting to take place in Leiden on 10-11 March. The venue is a 17th century castle, which has conference rooms that can accommodate up to 30 persons -- adequate for the ASAC itself (up to 26 participants) but restricting the number of others who may attend. It was agreed to work within the constraint imposed by this venue. E. van Dishoeck asked how payment will be arranged. A. Wootten said that NRAO reimburses the US participants who fly on US-flag carriers. The meeting will start at 10:30 on Friday 10th, so that most European participants can arrive that morning.

Possible agenda items for the Leiden meeting were discussed. Suggestions include the water vapour radiometer, receiver layout (Wild), 30-46 GHz issue (J. Carlstrom should be asked to attend, or at least prepare a report), antennas (at least for review), polarization (see also 13 Dec minutes), configuration (Wootten).

5. Working Groups

The list of Technical Working Groups remains to be completed and posted on the web site. (These have been posted at the links above, for the most part; one not yet in place is the Joint Receiver Design Group list). S. Guilloteau will send the European list to A. Wootten. R. Booth asked about the Liaison group. S. Guilloteau replied that the minutes from the first meeting are on the web site, and the first report will be produced shortly. These subjects are deferred to the next ASAC telecon.

6. Correlator

Input concerning correlator issues should be provided before the correlator PDR on 20-21 January in Charlottesville. C. Wilson asked whether the correlator limits the possibility of creeping configuration changes (sub-array operation). A. Wootten said that it’s probably OK, but will check. D. Emerson commented that the LO may be a limitation. S. Guilloteau is preparing a note on this.

***Revisions? Stephane – do you want to elaborate here?***

 

7. Ad-hoc Group Reports

 

  1. Polarization. R. Crutcher said that he, L. D’Addario and J. Welch will produce a first draft of their report by the next ASAC telecon, and a final report by the time of the Leiden Meeting.
  2. Total Power/Nutating Secondaries. J. Welch has volunteered to take the lead on this, with a report before the Leiden meeting. As a reminder, note that the ALMA/US prototype antenna will have a nutating secondary capable of up to 2 arcminute throw at a rate up to 5 Hz, a copy of the current 12m design. No plans exist for nutator on the ALMA/EU antenna or on the production antennas.

  3. Water Vapour Radiometer. J. Richer will prepare this report, together with R. Hills.

 

N. Evans asked what other studies and reports should be carried out. S. Guilloteau said that the report from the December receiver meeting will be completed shortly, and he will present a summary at the next ASAC telecon. A.Wootten will report on the results of the upcoming correlator PDR meeting. A. Wootten also said that a WG on configurations has been formed and will meet monthly, with a face-to-face meeting in Tucson on 20-21 March; a PDR will be produced by the summer. N. Evans said that relevant white papers should be available at least one week before the Leiden meeting.

8. AOB

A.Wootten announced that, on the US side, Mark Rafal has been appointed Project Manager. R. Brown becomes NRAO Deputy Director for International Affairs, and P. Napier is Head of the Antenna Division. The contracts for both antenna prototypes should be signed shortly.

M. Ishiguru mentioned plans for the 17-19 February meeting in Tokyo. Immediately beforehand (on 16 Feb) the ALMA Liaison Working Group will meet, major issues being the 6-8m antennas, the 900 GHz receivers, and the possibility of a very large FX correlator.

9. Next Meeting

The next ASAC teleconference is on Monday 14 February 2000. A tentative agenda has been posted.