SCIENTIFIC ADVISORY COUNCIL OF THE
CANADA-FRANCE-HAWAII TELESCOPE

REPORT OF THE 54th MEETING

October 29-31, 1998, Kamuela, Hawaii

Preliminary Notice:

Some parts of the report which required more discussions from the Agencies and the Board regarding the Megacam survey time, the Wide field infrared camera and the NGC committee draft report have been deleted from the original version.


The meeting was attended by all SAC members: John Hutchings (chair), Jean-Gabriel Cuby (vice chair), Alain Mazure, Pierre-Olivier Lagage, Thierry Forveille, Paul Hickson, Michael West, Gilles Joncas, Richard Wainscoat, John Tonry. The sessions were open to all interested CFHT staff, of whom presentations were made by Derrick Salmon, Pierre Couturier, Dennis Crabtree, Jean-Luc Beuzit, Christian Veillet. Klaus Hodapp was invited from UH to present his WIRCAM design.

A summit visit was made by most of the SAC on Oct 28, which included a tour of the Gemini building and telescope.

There were several additional TAC meetings to discuss the scheduling of the 1999 I semester.


Agenda

The agenda for the meeting were as follows, with supporting material or information indicated in parentheses:
 

  1. Technical report (CFHT mailing)
  2. Users meeting and its publication (review actions)
  3. CFHT12K guiding (Wainscoat)
  4. Megacam survey/large program time and process (emails and mailing
  5. Queue scheduling (CFHT report for CFHT12K).
  6. New 5% slop permitted in scheduling nights per agency (CFHT to report)
  7. New proposed proposal process (see CFHT mailing)
  8. TAC process - (reports emailed by TAC chairs).
  9. Wide field IR camera working group reports (mailing and emails)
  10. NGC report (circulated to SAC, email comments)
  11. New instruments/modes proposed (as invited at users meeting)
  12. Decommissioning and long term priorities (CFHT director)
  13. OASIS and ARGUS
  14. CFHT archiving status (CADC email)


The report follows this order of agenda topics.


Recommendations

  1. CFH12k
  2. Megaprime
  3. Queue Schdeuling
  4. Proposal Submission
  5. Large Programs
  6. Common TAC
  7. WIRCAM/CIRMOS (Wide-field IR Camera/Cryogenic Multi-object Spectrograph)
  8. Instrument Priorities

1. HARDWARE AND INSTRUMENTATION

The CFHT technical reports are available on the CFHT web site and are not repeated here.


The SAC would like to record appreciation on behalf of the community for the hard work of the entire CFHT staff in successfully diagnosing and repairing the RA gearbox. SAC would also like to record appreciation of the timely and polished editing of the proceedings of the users meeting by Slavek Rucinski and Pierre Martin.

In discussing the instrument reports SAC noted that it would be useful for CFHT to post on its web site the following:


Recommendation 1.

SAC has the following recommendation regarding the CFHT12K guiding:

The SAC learned that the read time for the CFHT12K camera is likely to be less than one minute. Because the QE of CFHT12K is approximately double that of UH8K, exposure times will be shorter. This means that acquisition of guide stars is likely to become the major source of inefficiency in observations with CFHT12K. The SAC therefore recommends that CFHT take urgent action to make rapid computerized acquisition of guide stars with the PF Bonnette possible.


Megaprime

The Megaprime project was reviewed. The efforts on CFHT12K and the gearbox failure have impacted progress with Megaprime at CFHT. SAC has the following resolution concerning the Megaprime schedule:


Recommendation 2.

Considering that the installation and testing of Megaprime will be a major undertaking which could potentially preclude prime focus observations for a significant period of time, the SAC recommends that CFHT develop a plan for implementation of Megaprime which minimises the impact on telescope operations. The cost and feasibility of options such as the fabrication of an all-new top ring for Megaprime should be investigated. The loss of prime focus operations should not exceed two consecutive dark runs.

Considering the scientific importance of implementing Megaprime as early as possible, we also recommend that every effort be made to maintain the current construction schedule.


Archiving

Due to lack of time and absence of substantial issues, this topic was not discussed. Email on the subject from CADC was circulated to the SAC members.



 

2. TIME ALLOCATION  AND OBSERVING ISSUES

Megacam Survey Time

SAC began an email discussion on the allocation of survey and large programs with Megacam during the summer, and a number of discussions were held on the subject among SAC members and their community colleagues. The SAC spent cnsiderable time and effort in formulating suggestions that deal with these issues, also taking into account ideas received from Laurent Vigroux on behalf of CEA, and the negotiations and letter of intent with CFHT.


Queue scheduling

Recommendation 3.

At its last meeting, SAC recommended that queue observing be undertaken with CFHT12K in 1999 II, and requested a detailed proposal for how this would be implemented. However, no plan was presented. We urge that this be done as soon as possible, but without compromising other support activities.

CFHT has informed SAC that the additional workload required for queue observing of CFHT12K proposals scheduled for 1999 I, would exceed available resources. The granting agencies of the partner communities should be approached to request transfer of funds to cover costs for the additional workload. It was noted that the savings in travel expenses which result from queue observing would help offset some of this cost. CFHT must provide a realistic estimate of the anticipated cost of queue observing.

SAC would still like to see a specific working model for how queue observing will be implemented, and recommends investigating models developed by other observatories such as Gemini. If queue observing is to be offered in 1999 II, then a detailed proposal should be presented to SAC by early January and once approved, to the wider community by February 1.


Proposal Submission

SAC discussed the proposed web-based proposal submission that has arisen in discussions among several observatories, and approves its use for CFHT. Thus,


Recommendation 4.

SAC recommends that telescope time requests be made by the proposed new electronic submission. It supports efforts presently developed to implement such a procedure using the CFHT web page and its corresponding mirror sites. This new procedure should be instigated for the next (1999 II) semester and be available on Feb 1 after it has been checked out at least one month in advance of this date.


Scheduling Flexibility


CFHT informed SAC that the flexibility of allowing up to 5% deviation from strict agency quotas, as recommended last meeting,  has been very helpful in optimising telescope scheduling.


Joint programs and large programs

SAC discussed the recent efforts to coordinate the CTAC and CFGT meetings and support joint proposals. The two chairs reported that considerable extra effort had been made for the 1999 I semester, and that both committees felt it is a worthwhile effort. SAC acknowledges the progress made in this review process, and recommends it is pursued. This process might involve the University of Hawaii in case of joint proposals involving it. It is recognized that some problems remain, and SAC consequently makes the following two recommendations.

In order to improve the evaluation of and the time allocation process for large programs, be they joint or not, SAC recommends that:


Recommendation 5.

Large program proposals grouping a significant number of scientific objectives should be split into individual  proposals - or at least a significant number of them - and a master proposal shall be submitted explicating how the individual proposals are grouped. In recommending that, SAC acknowledges that, should only part of the individual proposals be granted time, the data will be made available to all PIs of the other proposals.


Considering that the new modes of operation of CFHT will require closer collaboration and communication between communities, considering that the MEGAPRIME survey programs will require a common review process, SAC recommends that:


Recommendation 6.

A common joint TAC should be created in replacement of CTAC and CFGT for the evaluation of all Canadian  and French proposals to CFHT. This common TAC shall preferably be operational by September 1999 for the evaluation of the proposals for semester 2000-I.

SAC suggests that the organization of this common TAC is elaborated by a sub-committee of CTAC and CFGT members, with representatives of NRC, INSU and CFHT. The final organization would be reviewed by SAC not later than March 1999.


The above recommendation could also include UH if they were interested in participating.


3. FUTURE INSTRUMENTS AND PRIORITIES

WIRCAM/CIRMOS

SAC had a short report from the IR working group and had a presentation of the design for wide field IR camera (WIRCAM) by Hodapp.

Options for a pure camera (WIRCAM), or for a Cryogenic Multi-object Spectrograph (CIRMOS) were presented. The incremental cost of building a simple multi-object spectrograph over the cost of a pure camera was estimated to be 30%; the gain in scientific capability is substantial.  SAC has the following recommendation and charge to the working group:


Recommendation 7.

SAC still has strong support for the construction of a wide field infrared camera, both for its scientific potential, and to ensure that the bright time on CFHT remains competitive in the mid-term.

 SAC would like to see a number of specific points addressed in the next report of the working group:

    1. a study of a dual cryostat system for easier exchange of the cold focal masks
    2. consideration of an internal focusing mechanism, such as a pupil plane pyramid or equivalent.
    3. a detailed scientific case for the instrument
    4. a discussion of the timescale on which the instrument could be built considering in particular detector availability.
    5. examine the proposed guiding scheme for ability to find enough signal at all galactic latitudes.

NGC committee draft report

SAC read and discussed the draft report of the NGC committee. The general verdict was similar to the view sent by individuals at the invitation (to all SAC) of the Board chair, and to that reported from the agencies meeting. The opinion is that the report does not discuss an immediate CFHT replacement, nor does it relate the main astronomical questions discussed to any telescope or instrument. It is felt that this or some new committee needs to make this link, at greater length and as quantitatively as possible in terms of telescope aperture and instrumentation, to be of use in the planning for the next 10 years.


Instrument priorities

SAC discussed proposals for new instruments or modes, as invited at the Users meeting, and in our last report. There were three new AOB modes or capabilities: interfero-coronagraph; a dedicated coronagraph using refurbished Monica; and NIR integral field spectroscopy. A proposal for Espadons was also reviewed. It was noted that no submission was received for the coude upgrade proposal mentioned at the users meeting.

 SAC also discussed priorities beyond the major projects that are under way, including the CFHT IR camera, which is now anticipated for a year from now, and priorities for decommissioning instruments and foci. The current demand for Argus and OASIS were also discussed. The SAC has this recommendation to cover all these issues:


Recommendation 8.

The SAC endorses the priorities expressed by CFHT, namely that CFH12K should be brought on line as soon as possible and CFHT efforts should then be primarily directed towards Megaprime.  SAC and CFHT recognize the importance of CFHT-IR, and CFHT should see to its expeditious implementation concurrent with work on Megaprime.

Other priorities include the fiber feed for GECKO and the upgrade of AOB-KIR for spectroscopic capability.  These are small enough projects not to interfere with the main priorities.  CFHT and the SAC agree on the value of ESPADONS, and work on it should proceed as time and resources permit.

The coude mirror train should be restricted to only coude-UV as soon as the GECKO fiber feed is available.  SAC agrees that the f/35 secondary and the FTS be decommissioned after semester 2000-I, and urges the various TACs to take note of this in evaluating proposals to use the FTS over the next year. UV coude train should also be decommissioned at that time, whether or not a UV optics and fiber feed has been obtained.

The REDEYEW camera should be decommissioned as soon as CFHT-IR is available, unless it is required for an FTS run (prior to the decommissioning after semester 2000-I).

Finally, the SAC agrees that the difficulty in accumulating enough demand to schedule OASIS on the telescope, and the greater capabilities of OASIS with respect to MOS-ARGUS (although with smaller spectral coverage) dictate that CFHT only offer OASIS for use.  At its discretion, CFHT may want to make exceptions to this in cases where MOS-ARGUS is necessary to complete projects already in progress.