The effect of the instrument environment on the Altair AO system
Julian Christou, Benoit Neichel, Francois Rigaut
The Altair AO system at Gemini North has been in regular operation for many years. Over the past few years we have been routinely monitoring its performance looking at the telemetry circular buffers from the nightly tuning, in particular the residual tip-tilt (TT). We present analysis of these data which illustrate how the instrument support structure (ISS) environment affects the residual TT and how different components of the TT signal is affected by the instrument compliment.