Welcome to the DESI Data Model!¶
The DESI Data Tree¶
These pages define the directory structure and file formats for DESI
data products relative to a root directory DESI_ROOT.
Each data release has its own DESI_ROOT, e.g. the
Early Data Release
at https://data.desi.lbl.gov/public/edr.
Data Directories¶
Directories under DESI_ROOT:
spectro/data/NIGHT/EXPID/: Raw data
spectro/redux/SPECPROD/: Processed spectra, classifications, and redshifts
target/: Target selection and fiber assignment catalogs
vac/RELEASE/: Value Added Catalogs
The following directories are more expert-level (e.g. pipeline calibration inputs) and are documented for DESI collaboration internal use and may not be included in data releases:
survey/ops/surveyops/: Data files used for day-to-day survey operations
spectro/desi_spectro_calib/: Spectrograph calibration data
protodesi/: Data and logs from the ProtoDESI campaign (no spectra)
$DESISURVEY_OUTPUT: Outputs from desisurvey and surveysim
$DESI_SPECTRO_SIM: Simulated spectro data
$DESIMODEL: Data used for simulating DESI
Other information¶
Bitmask definitions and environment variables used by the DESI data pipelines:
Imaging data and their catalogs are documented separately by the Legacy Survey.
The desidatamodel package on GitHub includes the data model input files and some Python utility code for generating and checking data model files. These links will be useful for developers:
References¶
Target Selection: Myers, A. D., et al. 2023, AJ 165, 50
Spectroscopic Pipeline: Guy, J., et al. 2023, AJ 165, 4, 144
Early Data Release: DESI Collaboration et al. 2023