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The two keywords refering to the original D(ata)-tape, are FITSTAPE and FITSFILE. Selections can be made on these keys, but some care should be exercised when doing so. The tape and file information is NOT part of the catalogue, in the sense that it does not appear in the actual records, but is stored separately and addressed via pointers. There are safety reasons for having this setup, not least because the tape name and file number have to be stored totally secure, or, if they were in some way corrupted, the archive software would never find the data back.
Thus, if a search for a FITSTAPE is specified, what happens is that the tape information is first accessed via a pointer, and then tested. It is a very IO intensive process, which, if done for every record of the catalogue, is an extremely time consuming operation.
Therefore, if you wish to search for a particular tape, the best thing to do is to search on another catalogue item as well: the tape information will then only be accessed if the additional search specification(s) are satisfied. The catalogue item to use that springs to mind is the DATE (or NIGHT) of observation, not least because the date is an indexed item. A reasonably reliable strategy is to apply a window around the (approximately) know date of the observations:
SEL DATE = (<first> TO <last>) & FITSTAPE=I*nnnn
SEL NIGHT = (<first> TO <last>) & FITSTAPE=I*nnnn
If you do not know the date, but for instance do know of a particular object on the tape, search on that object first (see above), and do:
LIST ...., DATE, FITSTAPE, [FITSFILE,]....
Subsequently, now knowing a date, search for the whole tape using a date window. As a final check you may list the selection thus obtained and inspect the FITSFILE item, in order to see if the whole tape was covered by the date window; some D-tapes do contain data taken over a longer period of time.
If you don't have any additional information about the tape you want to find, and only have the name to go on, then it may be better to search for it in batch mode, by using the mailserver access mode (see section ).