Pressure and temperature stabilization of an existing Echelle spectrograph

The Echelle spectrograph FOCES, that was operated at the 2.2m Calar Alto telescope between 1995 and 2009 will be used as a test bed for a number of different stability issues related to high precision radial velocity spectroscopy. We utilize FOCES to study spectrograph stability, illumination stability and fiber transport stability. The layout of this laboratory experiment will be presented in this paper together with the required and desired spectrograph stability with respect to both pressure and temperature. We will present technical concepts how to reach our stabilization goal as well as first results from the spectrograph thermal stabilization efforts.

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