Minutes for Telecon for Dec 11, 2001

Present: Churchwell, Benjamin, Whitney, Watson, Meade, Ashman,
Indebetouw, Wolfire, Stolovy, Marston, Jackson, Babler, Mathis,
Wolff, Dickey, Clemens

Reminder: GLIMPSE group email address is sirtf@astro.wisc.edu

Next telecon: Tuesday Jan 15, 2002, 11 am CST, same #


Progress Updates

  Quick Look Validation Tool (QLVT) - Mark

   Mark described the features of the current version of the QLVT.
   Check out the following web site for illustrations of the various
   displays used in the QLVT: 

   http://www.astro.wisc.edu/sirtf/Team/Processing/qlvt/index.html

   The user can display all 4 IRAC bands with the corresponding 2MASS
   field for bands 1 & 3 and the corresponding MSX field for 
   bands 2 & 4.  Dan suggested being able to look at the 2MASS data
   for both the 1 & 3 and 2 & 4 fields. Similarly for the MSX data.
   Other options for the display of the images include having the
   same scale and orientation, grids on or off, align in galactic
   or equatorial coordinates. The Validation display allows the user 
   to set various flags and comments which will be written into the fits 
   header of the calibrated image. See the displays on the web site
   for a more complete idea of the current features. Note the headers are
   changed at this stage but not the image.
 
   Still need to think about the SLVT (Slow Look Validation Tool).
   Would be nice to overlay bad/saturated/banded/latent/etc pixel
   locations over the image. 

   Also still need to work on the interaction of the QLVT with the pipeline.
   Remy has written a AOR Selector GUI which color-codes the data
   according to its quality (i.e. Red=Big problem; Yellow=Some problems,
   need SLVT; Blue=OK, send data to next stage in pipeline;Purple=
   data have already been processed). The survey tracker could tie
   into this tool.


  Data Simulations - Remy

   We are simulating IRAC images using Matt Ashby's IRAC simulator
   using the 2MASS Point Source Catalog, MSX bkgs, added banding effects
   to ch 3 & 4 images (banding was not included in the IRAC Simulator),
   and colored sources.  Remy emailed a ps file Monday of the simulated
   images.  The file sent out was essentially a "worst case" data set
   with all the instrumental effects still in the data.  We can also produce
   a "best case" data set with no instrumental effects added to
   the data (thus assuming the SSC pipeline is removing
   the effects).  These data sets will be used in completeness, photometry
   and pipeline development work.  


Calibration issues - Ed & team

   SSC is promising flux accuracies of 2% relative and 10% absolute.
   Is this good enough for mosaicing?  Will this meet our science 
   calibration requirements?  If not, can we do better and at what
   cost?  Remy has a list of secondary calibration sources. 
   There is only one of SSC's calibration sources in our survey region.
   The consensus of the group seems to be that we can use our secondary 
   calibration sources to check the SSC calibration, as a sanity check
   during validation but we wouldn't be recalibrating our data. If there
   are problems, then we would go to SSC with our concerns. 
   Hope to schedule a telecon with Martin Cohen to discuss 
   this further with him.

Level A Pipeline Validation Issues - Ed & Team

   We need to establish criteria for validation.  How much of
   whatever instrumental effect (e.g. banding) can we tolerate?
   The simulated data should help here plus the Data Specifications
   Documents should spell this out.

Catalog entries - Ed & Team

   Local noise limits or flux limits?  All bands or band by band?
   After much discussion we settled on the following for our two
   Point Source Catalogs:

   GBSC - define average confusion limit in each band.  all sources
          20 sigma above that in any one band included.  data not
          making that criteria in the other bands either not appear
          in the catalog or appear with appropriate flags.

   GPSC - best effort catalog.  try to achieve 5 sigma based on local
          noise.
  
Science Constraints on Data (break points) - Ed

   How good does the photometry have to be to achieve the science
   we want? The science categories with assigned names are listed
   in the Dec 11 telecon agenda email sent out by Ed on Dec 07. 
   This information is needed  soon ... need it in January.
   It will go into our Data Specifications Document. 

Miscellaneous

   Ed, Bob, Susan, Remy, Tony, Mark, Christer, Jim, Mike, maybe Dan
   will be going to the AAS meeting.  Bob will organize a gathering
   of GLIMPSEers at the meeting.

   Tony gave us a heads up on when we need to get information in to the
   SSC on our validation observation, our 10 hrs of DDT time very early
   on in the SIRTF mission.  SSC will want us to provide criteria for
   our validation observation, the AORs, etc by MARCH 2002.

Happy Holidays!

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