History

The CADC started the Hubble Space Telescope Project in March 1986. The center became operational in middle 1987 using standard calogue data only because launch delay of the Hubble telescope.

Very soon, in order to distinguish themselves from the main STScI center, the CADC started implementing important added-value features to complement what was already available.

In principle, the files delivered by CADC are exactly the same as the ones delivered by STScI and ST-ECF. But sometimes, the processing software versions are different. Updates are installed more frequently at CADC and ECF and usually later at STScI because of operational constraints. But for 99.9% of the cases, we are all running the same basic infrastructure. When differences are detected, it is often due to cosmetics considerations and are not affecting the pixels array.

The CADC is also responsible of producing the previews which are in used in all three HST centers. This way, the CADC is insuring that its pipeline software is running correctly when the observation become public, usually one year after the acquisition date. The CADC has no rights to distribute nor manipulate non public data.

Observations searches Using web interface

The HST web based search interface provides a means to search the HST archive. Currently, the page limits the number of rows to be returned. The default is 100 rows, but the limit can be increased to a maximum of 1500 rows. This limit is imposed due to the length of time needed to render the search results in HTML. Even 1500 rows will take some time to render in HTML. However, if you wish to make a number of searches and requests, the web interface should serve you well. You may wish to perform the same basic search, but limit the results by including a filter and/or observation time limit.

Once your selection have been specified and you are getting your search results in an html table, you could then select the datasets you want to get from CADC by marking them (checking the "Mark" box on the left most column. Then just hist the download data button

All public HST images are now available in the VO registeries as CADC service. Please use any VO registry compatible tool such as Aladin to browse and get HST data from CADC.

In addition, one could use the CADC's new OCTET application which main feature is its ability to search the entire sky for common observations in selected bandpasses.

The CADC is also providing a convenient programmatic interface to its entire HST datasets collection. Please consult the on-line manual for more information:

This interface allows you to access directly the HST dataset of your choice. For this though, you will have to know the filenames associated to each datasets. Please consult the CADC's documention page for HST filenames for each instrument and project.

For the HLA archive, just replace the HSTCA archive by HLA

In short the interface could be use the following way: