Re: Science goals

[Ray Carlberg <carlberg@moonray.astro.utoronto.ca>]

Christian -- the issue of what drives the survey is a significant one.
I did read all the suggestions.  On the Canadian side, after
discussion with a fair number of people (including explicit email from
the outgoing/incoming Directors General), a large survey will only
receive wide support if there is a clear, exciting, scientific goal
which absolutely demands such a large amount of time.  If the survey
is proposed as a lot of smaller projects merged together then the
Canadian view has been that those would most efficiently done as
individual PI projects. Consequently at this stage it seems a lot more
likely that Canadians will get behind a single "big issue" project
more readily than any other approach. This view is not unique. Other
projects motivated this way include the 2dF, the Sloan, VISTA and a
variety of smaller projects.

All three communities have very strong lensing interests and represent
the leading efforts in the world. It is nice that many of those people
have a very strong link to CITA so there is already a basis for
collaboration, should they desire. These thoughts have been the basis
for my approach, where this becomes the primary goal, but we explicitly
recognize various secondary goals. Without compromising the main
goal we can readily allow for time sequences and more filters than
the lensing alone would really justify. 

Given the small amount of time available it is important that we be
frank about what our communities are likely to see as supportable.