Tests of open-loop LGS tomography with CANARY

CANARY is an on-sky demonstrator adaptive optics (AO) system that in 2010 provided the first on-sky demonstration of open-loop tomographic adaptive optics correction using natural guide stars (NGS). Phase B of the CANARY experiment aims to extend the instrument from its original configuration by also measuring wavefronts from four off-axis Rayleigh laser guide stars (LGS). This upgrade allows CANARY to perform tomographic wavefront sensing over a 2.5arcminute field of view using any mix of up to seven off-axis wavefront sensors (four LGS and three NGS) simultaneously. AO correction within CANARY is performed on-axis along a single line of sight using a 52-actuator deformable mirror being controlled in open-loop. Here we give an overview of the Phase B LGS system, discuss the calibration of a mixed NGS/LGS tomographic system and present the recent laboratory and on-sky results from the Phase B commissioning.