Welcome to the “Centre d'Analyse de Données Etendues” (CADE) or “Analysis Center for Extended Data”. CADE provides maps of ancillary astronomical data to users in the astronomical community. The emphasis of CADE is on extended sky emission. The database is provided in the HEALPix sky pixelization scheme.

An increasing number of large survey projects use a unique hierarchical pixelization of the celestial sphere called HEALPix. CADE pursues a strategy of ancillary data ingestion in the HEALPix format, generating partial or all-sky HEALPix files from astronomical data that is represented using the more traditional local World Coordinate System (WCS) FITS format. The ingestion tool is based on the drizzling library, and uses a strategy where the surface of pixel intersection is computed as presented in Appendix A of Paradis et al., 2012, A&A, 543, 103. This method allows fast ingestion and guarantees the photometric accuracy of the transformation with minimal data loss during the transformation from a local WCS FITS map to HEALPix.

CADE provides astronomical data production in the HEALPix format, data archiving and diffusion to the community.

The service delivers

  • Extended, multi-wavelength data from astronomical large-scale surveys in the HEALPix format.
  • Uncertainty and/or hit count maps, when available
  • Meta-data that facilitates automated data analysis.
  • Non-public survey data sets, for internal project use (including Planck, Herschel). Please contact us if you would like CADE to host password-protected data for your project.
  • VO-compatible data, accessible through the Aladin software (http://aladin.u-strasbg.fr/).
  • The drizzling software library (in Python), which reprojects data from HEALPix to local WCS and is available here : http://cade.irap.omp.eu/dokuwiki/doku.php?id=software
  • A Web interface of the Drizzlib (DrizzWeb) http://drizzweb.irap.omp.eu/
  • NEW: The first SED Extractor tool (in Python), which extracts a Spectral Energy Distribution from HEALPix, WCS or mixture of HEALPix-WCS FITS files

People involved

If you have any questions or comments, please contact :

We thank Pierre Fernique, Laurent Cambrésy, Caroline Bot, Thomas Boch, Antoine Goutenoir, Gabriel Foënard and Anaïs Amato for their help.