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Calibration Reference Data System

Reference File Information by Instrument

Here you can find the specifics of each instrument's reference files as described on the SI websites. Please note that ftp-based shortcuts are provided to allow quick access (in most cases) to the reference files, which are stored on-line for convenience. If you choose to access the files via this ftp server, keep in mind that there is a known bug in using Safari; the recommended browser is Firefox. However, the most reliable method for obtaining reference files is via the archive.

If you need to request individual or multiple files from the MAST archive web site use the first nine characters of the file name followed by an asterisk, or the entire unique name given on the SI web pages linked to below. In order to retrieve reference files from MAST, you must overide the retrieval options. That is, once in the "Retrieval Options" window, you must override the defaults by entering the extension(s) of the file(s) requested. For example, if you are retrieving a bias reference file (with extension bia), enter "bia" in the box "or enter a specific extension:" and then submit your request.

If you wish to find out when new reference files are delivered for a specific instrument, you may subscribe to a mailing list designed specifically for that purpose. The xxx_reffiles_upd mailing lists, (where xxx is the instrument name; acs, cos, nic, stis, or wfc3), send out an e-mail whenever a new reference file is delivered and the database is updated for each instrument. To subscribe to any of these lists, send an blank e-mail to listname-subscribe-request @ (leave the subject and body blank). Example: acs_reffiles_upd-subscribe-request @

For the Active Reference Files links below, when you arrive at the page, click on the instrument name, and then on the reference file type of your choice.








Legacy Instruments

See also naming convention and reference file formats.

NOTE: If you choose to use the ftp access, there is a known bug with trying to access files via ftp server with the Safari browser. The recommended browser for retrieving the files is Firefox.