In addition to the "standard" Hubble Space Telescope archive, the CADC also provide access to other archive derived products which are groupeg into multiple collections but shared the same photons as the "standard" archives. They are or special observation projects or products issued from different, usually enhanced pipelines.

The HLA, or Hubble Legacy Archive, is a product of the Space Telescope Science Institute (STScI), the Canadian Astronomy Data Centre (CADC) and the ST-ECF. They are working together to optimize the future scientific return from the Hubble archives by producing enhanced data products and efficient data discovery and access services - collectively known as the Hubble Legacy Archive (HLA) - with the goal of capturing expertise in Hubble and assuring the maximum utility of Hubble data for long-term use by the community. The HLA provides footprints for ACS, WFPC2, STIS, NICMOS, FOS, and GHRS, enhanced image products for ACS and WFPC2, and grism spectra for NICMOS and ACS/WFC.

HLA Publication Acknowledgment

Users of HLA data sets are requested to include the following acknowledgment in any resulting publications: "Based on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESA) and the Canadian Astronomy Data Centre (CADC/NRC/CSA)."

CADC, the ST-ECF and the Multimission Archive at STScI (MAST) provide combined images from the Wide Field Planetary Camera 2 (WFPC2) on Hubble. The combined images are the products of the basic registration and averaging of related sets of WFPC2 images, referred to as associations, that is usually performed by archival researchers after the retrieval of individual images. The associations may have improved astrometry and registration provided by Hubble pointing jitter data (associations of Type A) or by cross-correlation (Type B).

Note: We strongly suggest potential users to use the HLA interface instead. The WFPC2B associations are not maintained anymore because of lack of man power.

The HLSP, or High Level Science Products archive. This archive will eventually includes all the extra products generated from the Hubble Space Telescope Archive. So far it includes:

• ESO Great Observatories Origins Deep Survey (GOODS) spectroscopy In the CDF-S

  As part of the Great Observatories Origins Deep Survey (GOODS), multi-object, optical to NIR spectroscopy in the Chandra Deep Field South (CDF-S) has been carried out, using the ESO FORS2 instrument mounted at the Kueyen Unit Telescope of the VLT at the Cerro Paranal Observatory, Chile. 1204 spectra of 930 unique targets were obtained in service mode with the FORS2 spectrograph providing in total 943 redshift measurements with quality flag A, B or C (A=solid redshift, B=likely redshift, C=potential redshift). 725 of the unique targets have an assigned redshift with quality flag A, B or C. The average of the redshift distribution is z=1.5 (median z=1.1). The typical redshift uncertainty is estimated to be +/-0.005.