Elixir data set T0005

From: Jean-Charles Cuillandre <jcc_at_cfht.hawaii.edu>
Date: Fri, 28 Mar 2008 16:53:46 -1000

 Hi,

This is to report that CFHT has delivered to CADC the replacement
files for the past 4 MegaCam runs of CFHTLS data by reprocessing
them with the B.3 flat-field recipe from Elixir in order to have
a consistent data set for T0005.

The difference in Elixir content for T0005 vs T0004 is:

        - First year (June 2003 - Summer 2004) of Elixir data
          using the B.2 Elixir retrieved by Terapix from CADC
          (this had not been done yet, Terapix still had the
          B.1 version).

        - End of 2006, all of 2007 A&B, and 08Am01 to be retrieved
          from CADC, all the data are B.3 at this time.

        - As the retrieval proceeds, MegaCam keeps pilling up
          new data, and T0005 will certainly include 08Am02
          and likely 08Am03 that is starting today. Elixir is
          releasing the data in mode B.3 until we fully qualify
          the B.4.

T0004 was a mix of B.1/B.2/B.3 - B.1 was really not so good as
a photometric correction, B.2 brought a significant improvement
(in early 2004) while B.3 represented a minor step forward (in
early 2006). Hence the recipe for all files in T0005 is quite
homogeneous, hopefully Terapix will detect an improvement.

Note that the new i' filter has only been calibrated with the
B.4 (SNLS) recipe and we're leaving it that way since the data
set is limited so far and data from the old and new filters
are not meant to be mixed (at least not the Deep, but what
about the Wide?).

                                        Jean-Charles.
Received on Fri Mar 28 2008 - 16:53:46 HST