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skils recommendations 

Following is a brief summary of issues and recommendations that were
made at the Mt Wash CFHTLS meeting. Comments are welcome, particularly
on the proposal to request an increase in the prop time.
 
Field Locations
1) strongly endorse Groth strip for one Ultra-deep/Sne
2) encourage further overlap with SWIRE survey
3) technical issue that 6x6 squares may be too large to be optimal
        for control of sample variance
 
Calibration
1) All science will benefit from 0.01 mag systematic error limits
        on all fields.
2) sne data requires 0.01 maq systematic, 0.02 mag random, with
        goals of 0.005 mag systematic and 0.01 amg random across
        all fields
3) An expert group on calibration should be established, at least in
        Canada, and ideally as a joint program between Canada, France
        and CFHT.
 
 
Proprietary Time
The scientific impulse to openly share facility data is deeply rooted in astronomy.
The Canadian community shares this view but has expressed
nearly universal concern that 13 months is too short. Arguments include:
1) The CFHTLS will be the first ever, large, deep, uniform imaging survey. Many
        of the fields overlap with locations of very deep surveys being undertaken
        with other instruments.
        Furthermore, the Elixir data is of a quality that is entirely sufficient for many
        scientific purposes with little further processing. The basic knowledge
        and capacity to deal with the uniform high quality CFHTLS data
        is becoming widely distributed in the astronomical community.  Whenever
        they are released the data are unlikely to languish.
2) The first few years are likely to create somewhat fragmentary datasets
        due to weather and other problems that will best left for publication
        for years two or three at which time the proprietary time will give
        a lead of only one year.
3) Undue haste in publication can be extremely counterproductive.
4) There is no advantage to the CFHTLS science community for such a short
        proprietary time.
5) Such a short proprietary time diminishes the possibilities of collaborative leverage
        of CFHTLS to gain other data, particularly given the
        somewhat slow, complex and diffuse structure for approval of collaborations.
6) Students are extremely concerned about being scooped. Rather than encourage
        people to concentrate on CFHTLS, a short proprietary time will in some cases
        cause people to concentrate on acquiring proprietary data at other telescopes
        which will give them control over their research science even if the
        CFHTLS results are published elsewhere. A longer proprietary time
        would allow a more balanced approach. Within the Canadian and entire
        CFHTLS commununity the
        CRO grant will be used to encourage open communication of research work
        and to help redress any serious incidents of student trampling.
7) Attracting science PDFs to a three year position where at least two of the three
        (or 4 of 5) years of the data will be openly available gives Canadian (or French)
        positions very little competitive advantage.
8) The 13 months is too short on the basis that most Canadian and French astronomers
   requesting followup time on a national facility need to apply through the TAC process
   to be awarded time two semesters after the discovery when the field is again
   visible. Someone with more flexible access to a telescope could make the same
   discovery in the database a year later, and, if appropriate scheduled, could scooop
   the person awarded time through the TAC process.

Based on the PDF timescale of 3 years, a feeling that the core work of most PhD projects
is done within about 3 years, and that it would be important to begin the release of
CFHTLS data while the survey is ongoing, it was generally felt that three years would
be an ideal proprietary time. Two years would be an improvement but would still be very
short. Five years would exceed the active phase of the survey. Although there are advantages
of a short proprietary time for recognition of
the important work done at the CFHT Corporation itself, the instrument builders
and the data centres, these considerations should not prevail over the scientific
motivations which brought these into existence.


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