ESO Science Archive
HARPS Advanced Data Products

Public HARPS data packages have been released by the External Data Products (EDP) group within DPD. These HARPS ADPs have been produced by the automatic HARPS pipeline developed by the Observatoire Astronomique de l'Université de Genève.

Release content
Currently the packages cover the first six and a half years of operation (2003-June 2009). Other data will follow as soon as possible.

Comparision to previous releases
The initial release in January 2008 consisted of packages covering the first 4 years of HARPS operations (2003-2006).
In June 2009 two additional years of HARPS packages were added (2007-2008). No modifications were done to the original packages.

Release notes
The HARPS pipeline is able to supply online science quality extracted spectra and radial velocities (RV) for solar type stars exploiting the full precision of the instrument. A RV precision better than 1m/s on long time-scales has been demonstrated in several works, see e.g. the recent Mayor et al., A&A 493, 639, 2009.

The spectral extraction is performed using the classical optimal extraction method by Horne (Horne, K. 1986, PASP, 98, 609). The basic processing steps consist in the order, in bias subtraction (the bias is computed on the overscan regions of the frame), spectrum extraction, flat fielding, wavelength calibration and if requested, the cross correlation computation.

The only masks available for accurate radial velocity computation are for stars of spectral types: G2V, K5V and M2V. However it has been demonstrated that these masks are sufficient to provide optimal RV precision (i.e. better than 1m/s) on all dwarfs of spectral types from late F to early M.

Data format
Each data package consists of a number of related files. The following naming convention has been adopted for the individual files.

    ADP.HARPS.<timestamp>_<rn>_E2DS_<ab>.fits         Extracted and flat-fielded 2D spectrum: one line per order
    ADP.HARPS.<timestamp>_<rn>_S1D_<ab>.fits          Extracted, flat fielded, de-blazed, wavelength calibrated and order merged 1D spectrum
    ADP.HARPS.<timestamp>_<rn>_CCF_<mask>_<ab>.fits   Cross correlation function (CCF), one per order, plus one line with the CCF averaged over all the orders.
    ADP.HARPS.<timestamp>_<rn>_CCF_<mask>_<ab>.tbl    Cross correlation function (CCF), one per order, plus one line with the CCF averaged over all the orders.
    ADP.HARPS.<timestamp>_<rn>_INT_GUIDE              Integrated guiding image (Note: Not always included)
    ADP.HARPS.<timestamp>_<rn>_BIS_<mask>_<ab>.fits   1D bisector

Data retrieval
HARPS data packages can queried and requested using the normal ADP Request form.

Contact
For any questions regarding the HARPS ADPs in the ESO Archive, please feel free to contact the DPD/EDP group. The email address is usd-help@eso.org, subject: EDP - HARPS.