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Description
The GINGAMODE database table contains selected information from the Large Area Counter (LAC) aboard the third Japanese X-ray astronomy satellite Ginga. The Ginga experiment began on day 36, 5 February 1987 and ended in November 1991. Ginga consisted of the LAC, the all-sky monitor (ASM) and the gamma-ray burst detector (GBD). The satellite was in a circular orbit at 31 degree inclination with apogee 670 km and perigee 510 km, and with a period of 96 minutes. A Ginga observation consisted of varying numbers of major frames which had lengths of 4, 32, or 128 seconds, depending on the setting of the bitrate. Each GINGAMODE database entry consists of data from the first record of a series of observations having the same values of the following: "BITRATE", "LACMODE", "DISCRIMINATOR", or "ACS MONITOR". When any of these changed, a new entry was written into GINGAMODE. The other Ginga catalog database, GINGALOG is also a subset of the same LAC dump file used to create GINGAMODE. GINGALOG contains a listing only whenever the "ACS monitor" (Attitude Control System) changes. Thus, GINGAMODE monitors changes in four parameters and GINGALOG is a basic log database mapping the individual FITS files. Ginga FITS files may have more than one entries in the GINGAMODE database. Both databases point to the same archived Flexible Image Transport System (FITS) files created from the LAC dump files. The user is invited to browse though the observations available from Ginga using GINGALOG or GINGAMODE, then extract the FITS files for more detailed analysis. The Ginga LAC Mode Catalog was prepared from data sent to NASA/GSFC from the Institute of Space and Astronautical Science (ISAS) in Japan. <p> Duplicate entries were removed from the HEASARC implementation of this catalog in June 2019. This is a service provided by NASA HEASARC .
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