HRSP-A dedicated echelle reduction software package for Hercules

摘要

A collection of computer programs called the Hercules Reduction Software Package (HRSP) has been developed in the Department of Physics and Astronomy, University of Canterbury, for the data reduction of echelle spectra obtained with the Hercules spectrograph. The main goal in writing a dedicated software package for Hercules was to achieve a highly-optimized reduction process that would provide the basis of a pipeline reduction performed at the Mt John University Observatory. Since the spectrograph has no moving parts, the spectrum produced in the focal plane does not move or change, so that the same reduction procedure can be applied to all CCD images. An optimized routine written especially for Hercules is always much more efficient and reliable than any general-purpose software available. HRSP is written in C and the whole reduction procedure is performed on standard FITS files. A standard echelle reduction is applied, including the background and cosmic ray subtraction, order extraction, flat-fielding, normalization and wavelength rebinning. A special feature is the radial velocity determination by crosscorrelation, which has been tested extensively over the past two years proving that Hercules is capable of delivering the high-precision radial velocities needed for detailed studying of binary stars, stellar pulsations, extra-solar planets and other related fields.