Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.stsci.edu/hst/observatory/documents/isrs/cdbs.query.isr.pdf Дата изменения: Fri Nov 14 16:36:29 2003 Дата индексирования: Sun Dec 23 07:15:44 2007 Кодировка:

Instrument Science Report OSG-CAL 97-05

WWW Query Tool for CDBS
C. Tullos August 14, 1997

ABSTRACT Using the World Wide Web, direct query-access has been made to the Calibration Database. All eight science instruments' reference data, plus photometric and spectrophotometric standards can be seen. By using wildcards, a user may retrieve information on all reference datasets or by using various qualifiers, the user has the ability to narrow the search down to very particular sets. The information retrieved not only lists the existence of filenames for particular modes of operation, but critical information about when the reference data has been archived and when it has been installed for pipeline calibrations.

1. Introduction
The calibration database holds calibration reference data for all of the science instruments which have ever existed on board the Hubble Space Telescope. The database holds over forty-four thousand distinct modes of operation for all eight science instruments. These modes manifest as database entries for calibration parameters or pointers to over ten thousand differerent reference files. Other information is available for each set of reference data, such as the DADS archive date, useafter dates (which define the time period for which each calibration file is applicable), the date/time when the installation took place in OPUS, plus the observation begin and end dates, indicating when the observations were taken to produce the calibration reference data.

2. Science Instruments and Modes
Numerous parameters for each science instrument define its operating modes. These act as dependencies in which each reference data set is chosen, depending on each calibration type.

1


Table 1. Observation Parameters for Science Instruments
NICMOS
NREAD CAMERA FILTER READOUT SAMP_SEQ

FOC
CAMMODE OPTELT2 WAVELENGTH LINEOFF PXFORMT UNI_FILE_NAME LINEPFM SAMPOFF OPTCRLY SAMPPLN OPTELT1 SMMMODE

WFPC2
MODE ATODGAIN FILTER1 FILTER2 SERIALS SHUTTER

FOS
FCHNL DETECTOR APER_ID OVERSCAN FGWA_ID PASS_DIR NXSTEPS POLAR_ID APER_POS WAVELENGTH

STIS
CCDAMP OBSTYPE OPT_ELEM SCLAMP APERTURE CCDGAIN BINAXIS1 CENWAVE BINAXIS2 CRSPLIT CCDOFFST LAMPSET DETECTOR

2


SYNPHOT
COMPNAME

MULTI
FLD_NAME TARGETID OBSMODE

WFPC
CLOCK FILTER1 FILTNAM1 MODE FILTER2 FILTNAM2 CAMERA SHUTTER PHOTMODE

HSP
TYPE THRESH VGAIND DET_NUM VOLTAGE APER_NAME

GHRS
GRATING SPORDER APERTURE DETECTOR TARGETID

3. The Query Tool
CGI scripts and Perl are used to access the Sybase database holding all of HST's calibration data. The query tool allows the user to retrieve with specialized queries using the various forms, depending on instrument and calibration type, or more generalized queries using wildcards for the reference file names. Each specialized search gives a list of calibration file type dependencies to be used in the search (as shown above). The query tool also allows searches to be made using Observation Dates or Useafter Dates.

3


Top Page After an instrument is selected, the user must supply a reference file name (with wildcard options), or choose a calibration type. If a wildcard is used, one might retrieve, a list of all WFPC2 calibration reference files. This is not recommended, for the return from the database will be very large. Using various forms of a wildcard input, the user can pare down the search.

4


Specfic Calibration File-Type Page For example, the WFPC2 was chosen along with a calibration type of DRK. A page specific to that instrument/calibration type appears, only giving the parameter choices which are defined by the file-type dependencies. Again, wildcards may be used. Any combination of the options and input boxes is allowed.

5


Preliminary Results Page After specifying the values of the query parameters, the tool gives a set of preliminary results. This is a subset of the total information about the reference data. It is intended for a quick look at the information retrieved. Each instrument group can define exactly what they want to see at each level. At this stage, a user would determine if the retrieval has been successful, and has the option to complete the process by displaying an expanded information set.

6


Expanded Results Page For this example, the WFPC2 /DRK (Mode=FULL, A2DGAIN=15, and SERIALS=ON), has given all of the information which is known about each calibration reference set. This includes information about the configuration of the science instrument, when and how the data was taken by HST, when the data was put into CDBS, OPUS, DADS, and all available comments.

7


4. Conclusion
The CDBS Web Query Tool provides an easy way to review the database for current and superceded instruments. Comprehensive information about each calibration reference dataset is available. Since most of the calibration data is online, plans for linking this tool directly to the data via the Internet is planned.

To access the CDBS Web Query Tool, enter the following URL:

http://www.stsci.edu/ftp/instrument_news/Observatory/query/query4.html

8


9


10