McMahon: The VISTA Hemisphere Survey (VHS)

The proposal aims to image the entire Southern celestial hemisphere in
four  bands. The panel  agreed that  the proposal  has a  large legacy
value.   However the total  time required  is very  large and  the PSP
believes  that  covering the  sky  in  J+K  is a  considerably  higher
priority than Z+Y.

At the beginning of the proposal, it is mentioned that 7500 deg2 could
be surveyed  in Z+Y  initially, but the  proposal does  not explicitly
discuss which 7500 deg2 of the sky are considered.

The proposers do not discuss  the science goals behind the annual scan
of the  SDSS SGC equatorial strip.  How much time is  being devoted to
this? Is it important to do this in all filters?

The proposers discuss prioritizing the targets but it is not clear why
that particular strategy was selected, nor what scientific gains would
accrue.  Since  this approach  would certainly have  an impact  on the
efficiency of  the survey, the  proposers should discuss  the detailed
observing plan and the perceived advantages and costs .

The Panel strongly recommends that the PI submits a new proposal which
focused  on the science  that can  be achieved  by covering  the whole
southern sky in J+K only. If the  PI wishes he could add, as an option
to be implemented at a  later date, the additional observations in the
Z+Y  filters. Of  course  the incremental  scientific objectives  that
could be achieved  with these observations should also  be part of the
optional proposal. The  panel felt that this strategy  could provide a
legacy database at the earliest opportunity.

The panel asks the PI to  contact Castander to discuss the Z+Y imaging
in the area  of the sky proposed by Castander (to  be observed by DES)
and to  determine how this would  add to the  scientific objectives of
the survey.