The first four years of SONG data: lessons learned
Grundahl, F.

Abstract

SONG has been in a stable mode of operation since mid-2014. In this talk I will give an overview of the data-processing from raw to final iodine-velocities and give examples of the data-quality and instrumental performance. The pros and cons of using iodine for SONG are also discussed.The problems and challenges for the long-term stability of the radial velocities will be discussed and the status of the ‘one-year-problem’ addressed. A possible upgrade to the Tenerife spectrograph will also be discussed.