Reduction software

FIES reduction tool was further improved by Dr. Eric Stempels. The main new features include: a task which can analyst an incoming ThAr and replace the previous wavelength solution on the fly; an improved extraction of interlaced ThAr by not recentering the orders and eliminating the 'clean' algorithm. This improves the intra-night precision of radial-velocity measurements to 5 m/s, as long as the interlaced orders are properly defined, and have not too large widths, and; a complete rewrite in Python of how scattered light is subtracted. This method also works on low-resolution (2x2 binned) spectra.

FIEStool is now also script-able (FIESscript). This allowed the calibration sequencer script fies.calibs to be updated and provide the user the option to automatically pre-reduce the newly obtained calibration data (flats, ThAr, biases) into fresh master-frames, which will be used by the online FIEStool. This means that users can now automatically insert fresh calibration data into FIEStool just by running FIEScalibs.

A further improvements to be made are is the addition of a filter for cosmic rays. For low S/N spectra the cosmic rays or spikes are not filtered out optimally. Pre-fabricated master wavelength reference and master order definition files will be added to the FIEStool tar-ball distribution to help simplify the initial steps in data reduction (order definition and first wavelength solution).

Thomas Augusteijn 2009-05-14