CASB Report for April, 1999

Community Affairs and Communications

• Supported several tours, including the annual take your daughter/child to work day.

Project Management and Technical Infrastructure

• Antonio Volpicelli from OATo visiting to work on COMPASS database QA.
• Reviewed candidate resumes for GEMINI and STIS BOP positions.

MISSION SUPPORT

HST Operations

• Received two new GSPRs (Guide Star Problem Reports), but have not completed investigations.

• Participated in the monthly NGSS Users meeting.

STIS-BOP

• Printed moving-target finder charts for Jupiter and Neptune for the rest of 1999 to support Cycle 8 STIS observations.

NGST Studies

• Alessandro Spagna presented his preliminary findings on guide star availability to the NGST Operations concept committee. Whilst visiting STScI, he also attended the NGST detector workshop and presented a poster on his results.

DIGITIZED SKY SURVEY

Plate Scanning

• Completed scanning the latest ROE shipment along with a few POSS-II plates. Started to rescan a set of SERC-J plates due to concern about laser monitor stability when the original scans were performed last summer.

• As requested, ROE has speeded up delivery of plate shipments to us. Returned one shipment and received another this month.

GAMMA Microdensitometer Systems

• Both machines operated within nominal specifications.

Data Compression/CD Production

• J survey mastering continuing.
• Planning for 2^nd CDROM jukebox to be on-line next month to enable us to access all available DSS-II images.

Archive Maintenance

• Certification of MOD ahead of schedule
• LMSI platters moved to Bloomberg

Software Development

• No progress reported in investigation of a GETIMAGE failure with the DSS-I, first reported by the NAOJ Astronomical Data Analysis Center.

GSC-II

Plate Processing at ECF and STScI

• Processing of the POSS-I E survey led to the discovery of an error in the plate processing software for handling GSC-I scan data containing negatively masked out pixels. Although the object detection software correctly forces the pixel values to positive, later plate processing software does not. This error potentially affects deblending, centroiding, and calculation of image features used in classification. A software fix has been implemented and regression testing is in progress.
• A known bug in the multi_centroider task has occurred more frequently as we began processing more crowded plates. The error, which causes a program crash due to a floating underflow, is under investigation.
• File sanctuary utilities to reverse the checkout of a sanctioned file, and to add required keywords, are under development.
• The most recent version of the apply_calib task was ported back to VMS for use with OOP files. This version includes a simple photometric and astrometric error algorithm; an astrometric mask capability; and permits not applying a geometrical vignetting function.
• Shipped tapes containing 235 scans of POSSI-E plates and 14 scans of POSSII-N plates to ECF for future processing and testing, respectively.

• At ECF, pipeline production was limited to 84 plates this month due to processing of crowded, low galactic plates. Rejected four plates; unable to read four scan images; unable to process two plates fully due to S/W failures.
• OATo staff are performing QA on ECF .did files. Also plan to do similar QA on STScI and OATo files and to attempt to quantify the various parameter changes possible.

COMPASS Database

• Production Loading, FindOverlapPlates, and Object-Matching tasks were run on the GEMINI first delivery fields.
• ApplyCalibs task was also run on these GEMINI fields. This is a post plate-processing recalibration run from the COMPASS database. The StarCounts QA program developed by Lasker is being run to verify the photometric quality.
• The new SpatialIndex library developed by JHU SDSS was ported to NT and Solaris. This library was tested and integrated into the production system for GSC2 database access using either a circular field or rectangular field query.
• The production GSC2Export task was written to export COMPASS database regions into FITS binary tables which correspond to the HTM regions (COMPASS file system). This was implemented in lieu of bit-interleaving to meet the delivery deadlines. The bit-interleaving scheme originally adopted has been deferred pending clarification of requirements from ESO.
• A SkyCat interface to the GSC2 export files was written with support from Edwin Huizinga. This interface demonstrated a successful database production integration, and verified high quality astrometry and object detection. This visualization of the GSC2 sources is quite impressive!
• GEMINI was given WEB access to a HTM FITS region for a format review of the SkyCat interface to GSC2 data sources.
• OATo staff are currently working at STScI on an IDL/C++ QA of GSC2 catalog data. This QA task is a user interface which accesses the COMPASS database and allows one to interactively produce graphics of GSC2 source positions, magnitudes and classification. QA on plate overlaps for verifying object-matching and astrometry is being developed. It is also a goal to have the option of running this task in a mode which can be scripted as a database production pipeline QA.
• FindOverlapPlates task was rewritten and tested. This will reduce the task time to a couple minutes for even very large plates. It is scheduled to go into the database production pipeline following the initial GEMINI delivery.

CALIBRATIONS: Astrometry

• Preliminary QA of the derived astrometric mask should a marked improvement in accuracy, however, a better mask based on more plate material is under construction.

CALIBRATIONS: Classification

• New tool to simplify creation of training sets and classifier decision trees is being delivered to operations.

CALIBRATIONS: Photometry (GSPC-II and DSS-I and -II)

• An error in the photosol task was discovered which limited the number of photometric coefficients written to four, even when more had actually been used with a higher order fit. The error has been repaired.
• Old KPNO data have been reprocessed using ARLO; GP2 will be updated with the revised data soon.
• Two of 17 CTIO runs have been reprocessed; 11 runs have been preprocessed and stored on CDs. Recovered most of the original data on old magnetic media.
• At OATo, reprocessed 11 nights from ESO runs 3 and 4. Completed IDL S/W build for building GSPC2.
• Continued vignetting studies using Tycho catalog stars. Investigation of U. S. Naval Observatory UJ 1.0 data, based on 3-minute Palomar Schmidt plates again was inconclusive because of saturation of the bright star images.

GSC-II Science

• At ECF, Fourniol and Mignani are using GSC2 data from pipeline output for two science projects. These activities also provide feedback for quality assurance of pipeline results.
• OATo sent an updated list of CRA plates to STScI. Agreed on a more efficient way to transfer the data.

Appendix – CASB Statistical Summary

SCANNING

S1. Low priority program to rescan crowded fields (|b|<30) originally done with 25 mu scans. The total number of S scans includes the 2 for the LMC and SMC plus 4 others with |b|>30 performed for research or STIS BOP support.

S2. This survey is an on-going low level-of-effort collaboration between the ST ScI and the AAO. About 25-50 plates have been added in each of the past few years.

S3. Low priority scans of the POSS-I -24 deg and -30 deg zones.

COMPRESSION

MO DISK ARCHIVING

GSC-II PLATE PROCESSING

GSC-II COMPASS DATABASE LOAD (Total Number Entries = 758,880,625)

GSC-II Dataset for V2.0 delivery (117 Fields)

GSPC-II OBSERVATIONS

GSPC-II REDUCTIONS