GDDS Spitzer Co-Is:

     Lin and I (mostly Lin) have worked out the AORs
for the SPITZER program. We are recommending that we 
use a larger rastering pattern than originaly intended.
This will give us more area to make local sky flats 
and more area for photometric/spectroscopic follow-up
with little loss in sensivitity. Using the sensitivity
estimator on the web our current AORs will give us the
following 5 sigma depths:  

     3.6     4.5      5.8    8.0 microns
    --------------------------------------
     0.95    1.85    12.5    16  micro-Jy

Note that this is deeper than what was shown in the
plot that Karl sent late last week. According to the
Figure in our proposal, this depth will get us to a
mass limit of 5E+8 at z = 2.

  The confusion-limit at 3.6 microns is reported to
be 0.5 micro-Jy, so there is not much more depth to
be gained in any case.

   Each field will be about 10'x15' centered on the
GMOS pointing. We cannot specify the orientation of
the IRAC rectangle in advance. Note that only the central
10x'10' will have all four IRAC bands, the other regions
will have only two, 3.6 & 4.5 on one end and 5.8 & 8.0
on the other.

   You can see the charts with the 3.6 & 4.5 micron
exposure maps overlain by going to the GDDS web site
and clicking on "charts". For those who have forgotten:

  www.ociw.edu/lcirs/gdds.html   GDDS nod&shuf

Unless there are problems with this, we will go ahead and
submit it to our contact person at IPAC.

Thanks,

Pat & Lin