From: Robert A. Knop Jr. (robert.a.knop@vanderbilt.edu)
Date: Sun Apr 04 2004 - 14:55:36 PDT
On Sun, Apr 04, 2004 at 02:53:31PM -0700, Greg Aldering wrote:
>
> In the previous email I neglected to give the spread in the loci - Y
> has a range of 0.7 mag in the new search, but only 0.3 mag in the 2003
> search. That is objects at the same magnitude in the new search have a
> variation in S/N of about a factor of 2. So, the reason this
> observation may matter is that it suggests a rather large variation in
> depth amongst the various images in the new search.
>
> This should be straightforward to check, and of course Rob may have a
> quick explaination.
The aperture thing I was mentioning last time -- first time around, I
was using a "way too big" aperture. There, the S/N would have been less
sensitive to variations in the aperture size. (It would also have been
lower.) Later during the process (by the acs02-03c subtractions), the
aperture was smaller, but I think most candidates had been found by
then.
-Rob
-- --Prof. Robert Knop Department of Physics & Astronomy, Vanderbilt University robert.a.knop@vanderbilt.edu
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