JWST Data File Naming Conventions

JWST data files have unique names that map to the original proposal, observation, visit, instrument, and detector used. 

On this page

See also: Getting Started with JWST DataFile Header Contents
ReadTheDocs (External Links): File Naming Conventions, Data Product Types

Science data file names

ReadTheDocs (External Links): Science Product Structures and Extensions

JWST science data files are "exposure-based" during their first stages of processing, meaning they contain only the values from a single exposure for a single detector. "Exposure-based" file names are constructed using information from the observation in the corresponding APT files, according to the stage 0 -2 naming schemes. stage 2 files are processed and combined with other exposures during stage 3  processing of the calibration pipeline, where products become "source-based." These are also known as "Associations," and their naming convention includes information such as target and source ID, instrument, and optical element according to the stage 3 naming schemes.

Each stage of processing creates corresponding intermediate and final data products depending on the type of data being calibrated, and the level of processing. The type of products are identified by the suffix of the file. The data product table contains the full list of all "exposure-based" and "source-based" product types for each stage of processing, including active links to more detailed descriptions of each kind of data product in the input and output columns.

Association file names

ReadTheDocs (External Links): Data File Associations

JWST association files follow a similar naming convention. Associations capture the relationship between exposures that are to be combined by design to form a single product. Association data products result from the combination of multiple exposures like dithers or mosaics, and are generated by stage 3 of the calibration pipeline. These products will have a file name that includes the "astronomical source target value in APT and observation parameters that will help users to map them to a specific proposal and observation. The software documentation contains the latest information on naming conventions for association files for the different association types.

Latest updates
Originally published