Performance of the extreme-AO instrument VLT/SPHERE and dependence on the atmospheric conditions

TL;DR

This paper evaluates the performance of the VLT/SPHERE extreme-AO system over two years, analyzing how atmospheric conditions affect its imaging quality and providing insights for optimal observation scheduling.

Contribution

It offers a comprehensive statistical analysis of SPHERE's adaptive optics performance in relation to atmospheric conditions, aiding better observation planning.

Findings

AO performance varies with atmospheric conditions

Data-driven scheduling improves data quality

Guidelines for astronomers on data processing

Abstract

SPHERE is the high-contrast exoplanet imager and spectrograph installed at the Unit Telescope 3 of the Very Large Telescope. After more than two years of regular operations, we analyse statistically the performance of the adaptive optics system and its dependence on the atmospheric conditions above the Paranal observatory, as measured by the suite of dedicated instruments which are part of the Astronomical Site Monitor and as estimated by the SPHERE real-time calculator. We also explain how this information can be used to schedule the observations in order to yield the best data quality and to guide the astronomer when processing his/her data.