CHOUGH: implementation and performance of a high-order 4m AO demonstrator

Bharmal, Nazim A.; Basden, Alastair G.; Bourgenot, Cyril J.; Black, Martin; Dubbeldam, Cornelis M.; Henry, David M.; Hölck-Santibanez, Daniel; Morris, Timothy J.; Robertson, David J.; Schmoll, Jürgen; Talbot, Robert G.; Younger, Eddy J.; Myers, Richard M.

Abstract

CHOUGH is a small, fast project to provide an experimental on-sky high-order SCAO capability to the 4.2m WHT telescope. The basic goal has r0-sized sub- apertures with the aim of achieving high-Strehl ratios (> 0:5) in the visible (> 650 nm). It achieves this by including itself into the CANARY experiment: CHOUGH is mounted as a breadboard and intercepts the beam within CANARY via a periscope. In doing so, it takes advantage of the mature CANARY infrastructure, but add new AO capabilities. The key instruments that CHOUGH brings to CANARY are: an atmospheric dispersion compensator; a 32 × 32 (1000 actuator) MEMS deformable mirror; 31 × 31 wavefront sensor; and a complementary (narrow-field) imager. CANARY provides a 241-actuator DM, tip/tilt mirror, and comprehensive off-sky alignment facility together with a RTC. In this work, we describe the CHOUGH sub-systems: backbone, ADC, MEMS-DM, HOWFS, CAWS, and NFSI.

Citation

Bharmal, N. A., Basden, A. G., Bourgenot, C. J., Black, M., Dubbeldam, C. M., Henry, D. M., …Myers, R. M. (2016). CHOUGH: implementation and performance of a high-order 4m AO demonstrator. In E. Marchetti, L. M. Close, & J. Véran (Eds.), Adaptive Optics Systems V (990948-990948-7). https://doi.org/10.1117/12.2231721

• Presentation Conference Type: Conference Paper (Published)
• Conference Name: Adaptive Optics Systems V
• Online Publication Date: Jul 27, 2016
• Publication Date: 2016-07
• Deposit Date: Nov 29, 2016
• Publisher: SPIE
• Volume: 9909
• Pages: 990948-990948-7
• Book Title: Adaptive Optics Systems V
• DOI: https://doi.org/10.1117/12.2231721
• Public URL: https://durham-repository.worktribe.com/output/1150614