WFI Data Format
Introduction to the section of the Wide Field Instrument (WFI) data handbook describing the overall format of the WFI imaging data products.
Overview of Content
WFI science data products are classified into different levels, each indicating the calibration stage and the types of products. These levels progress from Level 0 (L0) to Level 5 (L5), representing an increasing level of complexity. At a simplified level:
- L0 data encompasses packetized data from the telescope;
- L1 corresponds to uncalibrated detector ramps;
- L2 involves calibrated detector rate images;
- L3 includes re-pixelated products like co-additions and mosaics;
- L4 encompasses high-level data products such as source catalogs, 1-D spectra, and light curves; and
- L5 comprises products contributed by the Roman user community.
For a more comprehensive understanding of WFI data products, detailed information is available in the Data Levels and Products section.
The storage of all Roman WFI science data products will be in the Advanced Scientific Data Format (ASDF). ASDF is a file format created for the storage of binary data alongside human-readable and text-based metadata. Developed at the Space Telescope Science Institute (STScI), ASDF was created to overcome intrinsic limitations of the Flexible Image Transport System (FITS) format. Currently, it is also utilized by the JWST mission and the Daniel K. Inouye Solar Telescope (DKIST). Detailed information regarding ASDF is given in the ASDF Format Information section.
For additional questions not answered in this article, please contact the Roman Help Desk at STScI.