IPAC 2MASS Working Group Meeting #71 Minutes

IPAC 2MASS Working Group Meeting #71 Minutes 9/05/95

Attendees: R. Cutri, T. Evans, J. Fowler, L. Fullmer, T. Jarrett, D. KirkPatrick, G. Kopan, B. Light, H. McCallon, S. Terebey, J. White


  1. Status Reports


  1. Status Reports -- R. Cutri reported that the photometric calibration work on the April '95 data has continued. New techniques for computing the extinction corrections are being investigated. This activity revealed some peculiarities produced by PSF modeling error in KAMPHot for a particular set of scans. The new GALWORKS has now been run on all the April data. Stability of the twilight flats is being investigated, and sensitivity analyses are underway.

    B. Light reported that he has been working on the PROPHOT SDS and trying to make progress also on the CALMON SDS.

    L. Fullmer reported that she has been doing galaxy extraction analyses in support of the extended source processing software development.

    T. Evans has finished a draft of the MAPCOR section for the FDD. She also questioned G. Laughlin about the Macintosh postscript compatibility problem mentioned in last week's minutes; she reported that G. Laughlin believes a memory shortage is at the root of the problem, but the Macintosh involved is too old to upgrade, and so the flowchart software will be tested on the WIRE Macintosh.

    H. McCallon reported that he has almost finished implementing the 2-peg pattern-matching algorithm in the pipeline POSREC program, and tests will begin soon. This version of the algorithm does not yet contain the likelihood ratio formulation by M. Moshir, which contains magnitude-discrepancy terms and a penalty for missed matches; the current implementation contains only position-discrepancy terms. Howard will be pulled back into IRTS soon for about 1-2 weeks, since the arrival of data to be analyzed is imminent. He will try to get some tests of the 2-peg algorithm run before the IRTS data arrive, and he will try to get a memo off to D. Monet summarizing the results.

    J. White has the karloff analysis-version pipeline working; a problem was encountered when the merge program found no persistence to remove, and John has redelivered this program with a fix. He sent out the latest version (Rev. H) of the IPAC/Observatory Interface Document and is awaiting comments. He has also written a draft of the TAPELOAD SDS and is serving as the test case for getting flowcharts produced as postscript files via the drafting section in Spalding.

    G. Kopan reported that he had completed the comparison of his 2-D centroiding algorithm with the 1-D method proposed by D. Monet. The 1-D method required some modification and tuning before it approached the accuracy of the 2-D method, which it eventually did surprisingly (to some of us) well. The 2-D method retained a small advantage in accuracy, however, and will be retained in the design even though it does not execute quite as fast as the 1-D algorithm, since its speed is not a limiting factor, i.e., finding the point sources upon which to run a centroiding algorithm is by far the dominant CPU user in this stage of the processing.

    S. Terebey reported that she has been analyzing the peformance of the extended source processing software in the Rho Ophiuchus star-forming region. She has found some false extractions and is checking completeness and reliability. She will coordinate threshold-setting studies with T. Jarrett.

    T. Jarrett reported that he has written a draft of the GALWORKS SDS and has been analyzing extended source extraction results in the Coma and Hercules regions.

    J. Fowler reported that he has produced a draft version 3.0 of the FDD that includes the embedded postscript flowcharts. This was done with the help of M. Moshir, to whom considerable gratitude is hereby expressed. Some editing of the FDD text is still being done, and the goal is to have a draft into the hands of the developers for review by Friday morning. If that succeeds, then version 3.0 should be installed on the IPAC 2MASS web site early next week. Section 3 of the FDD has been renumbered because of recent design changes; anyone working on any corresponding subsections should be aware of the new numbering, which is as follows.

          3.1  EXEC
          3.2  TAPELOAD
          3.3  DARKS
          3.4  PCP
          3.5  PIXCAL
          3.6  PIXPHOT
          3.7  DFLAT
          3.8  FREXAS
          3.9  MAPCOR
          3.10 PICMAN
          3.11 PROPHOT
          3.12 BANDMERGE
          3.13 POSMAN
          3.14 GALWORKS
          3.15 CALMON
          3.16 QUALITY
          3.17 DBMAN