Minutes for Telecon for July 09, 2002

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

Next telecon: Tuesday July 23, 2002, 11 am CDT, 608-265-1000 #4112


Response to SSC Comments to our May Review

  Ed tried to call Tom Soifer and then sent him some
  email regarding the SSC comments to the May Review.

  Reliability Issues

    We can provide a catalog of high reliability but it will contain
    much fewer sources...2-3% of the sources in our "database".
    The database would aim for about 0.2 magnitudes brighter than the confusion
    limit. We'd like to make an estimate of the number of sources missing
    if we set 99.5% reliability for this catalog.
    Does 2MASS get 99.5% reliability in the galactic plane?

    We are working on automating our processing so the C & R analysis
    can go faster and we have more data from which we can do the analysis.
    We need a new round of simulations (of the W51 region using the
    new IRAC simulator, new PSF's, etc.)  Do we really need to get this
    done by August?  We want to develop the tools properly and then give a 
    better answer in October.  Ed requested from Tom Soifer that the
    deadline should be delayed until October for some of the responses
    to the SSC comments/action items.  To do this work it's critical that
    we get a bandmerger.  The 6.1 bandmerger is not ready for public release
    yet.  Note: We got a version on July 11.

    How many images do we need to process to get good enough statistics?
    Remy is working on simulated data for the W51 region.  It will take about
    2 weeks to make the new simulations, then about 6 weeks to develop the software
    tools. There are new issues when talking about ultra-high reliability.
    e.g.  We need to address the definition of "point sources".
    
    Our science drivers don't require 99.5% R, but what about other users?
    We can provide a catalog with high reliability and provide a database
    with lower reliability.  Does the SSC want only one catalog?  Will the database
    (including flags) become available through the SSC?

  Background & Confusion w/ longitude

    The SSC wants us to study the bkg and confusion levels with longitude.  
    Want us to maintain reliability across different areas in our survey.
    Maybe we can do some spot checking.  If what we learn does start worrying
    us, then we can think about alternative strategies. But it seems our
    planned simulations of W51 will provide a wide range of backgrounds 
    and source densities.

Project Status

    Database    
     
     Mike has been working on loading the 2MASS PSC 2nd Incremental Release
     into the database.  20-30 GB for the GLIMPSE overlap.
     There was a drive lost on the RAID system - still worked after losing a 
     disk drive..it operated in a degraded mode.  Stephan replaced it.
     There are 2MASS data for the W51 region so the 2nd Incremental Release
     PSC should be good enough for now. We don't need to get more data from 2MASS.

    Source extraction	

     Still working on band 4 and doing some DAOPHOT tweaking.  We are 
     currently using DAOPHOT but will compare those results with the SSC PSE when
     it becomes available

    Bandmerger

     We are supposed to get the SSC bandmerger this week (note: it was
     made available to us on July 11).  Remy has a bandmerger of sorts
     but it needs work

    Mosaicing

     Susan sent us the SSC mosaicer awhile back. A newer version may be out soon
     (got it July 15). To start with,
     Barb wants to mosaic the 2MASS images in the W51 region for use in the
     QLVT and to test out database functions.

    BCD header format content/position refinement
    
     Susan is involved with finalizing the BCD header content. Also, she/SSC
     is working on position refinement software which would be run after their
     BCD pipeline.  It will do correlations with 2MASS data and will put
     info in the header like the # of 2MASS sources it found in the frame
     that it used for the position refinement.
     Remy has also written a position refinement routine that we'd like to
     automate and have it use database queries.
    
    QVLT 

     Mark sent long detailed email about QLVT issues and the data processing
     group will discuss it and get back to him.

    Simulations	

     We need the new W51 simulations to exercise the pipeline and the QLVT
     since it has full 2MASS coverage and we could run lots of frames
     through the pipeline and QLVT.  There is a new IRAC Data Simulator out
     that needs to be installed and Remy needs a couple of weeks to produce
     a truth image from the W51 area. (version 20020515 was installed July 15)

W51 progress report

    A 1 square deg area in W51 has been observed at WIYN.  There are about 200+ stars
    with good visible spectra.  Our REU student Travis is participating in the
    project.  We hope to be able to associate IRAC colors of objects in our
    science verification area with good spectral types.

Workshop Planning

     SOC membership
     Tentative - John Dickey.  Dave Spergel and Dave Hollenbach have been contacted.
     Want to get the SOC together fairly soon to start talking about the agenda and
     structure of the workshop