The re-coated adapter pick-off and FIES mirrors were installed and aligned, the Echelle grating was aligned and a new shutter was installed and tested.
The new fiber unit was installed and aligned. Both the low- (R25000) and medium-resolution (R45000) fibers have a good throughput of 8-9%, but the high-resolution (R65000) fiber has only an efficiency of 2.5% which is a factor 2 lower than expected. FIES has now been incorporated in the exposure time calculator.
Various on-sky throughput measurements were done with different wavelength settings, and ranges. A final wavelength range of 364-726 nm was selected. More details can be found at
http://www.not.iac.es/instruments/fies/fies-comm.htmlThis page contains the latest on commissioning results.
Plans have been made to make a new fiber bundle with a better high-resolution fiber, but this is only expected to arrive in period 35. After its installation the current fiber bundle would act as spare.
As further improvements an exposure meter inside the spectrograph is being considered to allow as much as possible good data to be obtained under different weather conditions. For high-accuracy studies of radial velocity variation also an iodine cell is considered, but it should be checked if the required accuracy can also be obtained taking simultaneous ThAr spectra with the source spectra.
Thomas Augusteijn 2006-12-04