Re-commissioning of the VLT/UT4 telescope after the Deformable Secondary Mirror installation

Hibon, P.; Hammersley, P.; Selman, F.; Hau, G.; Duhoux, P.; Agnello, A.; Arranda, I.; Arsenault, R.; Blanchard, I.; Cerda, S.; Egner, S.; Johnston, E.; Parraguez, D.; Reyes, C.; Vernet, E.

Re-commissioning of the VLT/UT4 telescope after the Deformable Secondary Mirror installation

Date

2017

Authors

Hibon, P.

Hammersley, P.

Selman, F.

Hau, G.

Duhoux, P.

Agnello, A.

Arranda, I.

Arsenault, R.

Blanchard, I.

Cerda, S.

Abstract

During the 2nd semester of 2016, a new Deformable Secondary Mirror (DSM), part of the Adaptive Optics Facility Project at Paranal Observatory, was installed on the Unit Telescope 4. Starting end of November 2016, we then re-commissioned the telescope and the following three instruments : HAWK-I, MUSE and SINFONI. It is important to understand how a DSM, even if used in non-adaptive optics mode (i.e., in its rest/at position), can impact the operations and the quality of the observations. We discuss here the results of this telescope and instrument re-commissioning, the challenges and problems we met, and compare the new performance to the ones obtained previously with the traditional Dornier Secondary Mirror.