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To date, the OCAM2 system has demonstrated to be the fastest and lowest noise production ready wavefront sensor, achieving 2067 full frames per second with subelectron readout noise. This makes OCAM2 the ideal system for natural as well as continuous wave laser guide star wavefront sensing. In this paper we present the new gated version of OCAM2 named OCAM2-S, using E2V’s CCD219 sensor with integral shutter. This new camera offers the same superb characteristics than OCAM2 both in terms of speed and readout noise but also offers a shutter function that makes the sensor only sensitive to light for very short periods, at will. We will report on gating time and extinction ratio performances of this new camera. This device opens new possibilities for Rayleigh pulsed lasers adaptive optics systems. With a shutter time constant well below 1 microsecond, this camera opens new solutions for pulsed sodium lasers with backscatter suppression or even spot elongation minimization for ELT LGS. This camera has been successfully used for the first time on the CANARY instrument on the William Herschel Telescope. The final phase of CANARY is a demonstrator of a single MOAO channel for the proposed EAGLE instrument on the future European ELT. We will report on-sky performance with this instrument.

ELT-CAM is the E-ELT rst-light instrument that associates MICADO, the near-infrared imager, and MAORY,its multi-conjugate adaptive optics (MCAO) module. ELT-CAM will also come with a single conjugate adaptiveoptics (SCAO) capability motivated by scientic programs for which SCAO provides the best AO performance(e.g. exoplanets, solar system science, bright AGNs, etc).This SCAO capability will be developed within MICADO through a dedicated SCAO module with its naturalguide star (NGS) wavefront sensor (WFS), allowing MICADO to work in a SCAO stand-alone mode withoutMAORY, and inside MAORY with the same dedicated NGS WFS. MICADO and MAORY consortia are workingtogether on the development of this SCAO capability in order to perform a WFS trade-o study between Shack-Hartmann and Pyramid, to optimize the design of the NGS WFS as well as the interfaces between the twoinstruments. We present here the current status of the work done by the two consortia on the implementationof this SCAO capability for MICADO and MAORY.

CoRoT and Kepler have brought a new and deep experience in long-term photometric surveys and how to use them. This is true for exoplanets characterizing, stellar seismology and beyond for studying several other phenomena, like granulation or activity. Based on this experience, it has been possible to propose new generation projects, like TESS and PLATO, with more specific scientific objectives and more ambitious observational programs in terms of sky coverage and/or duration of the observations. In this context and as a prospective exercise, we explore here the possibility to set up an all-sky survey optimized for seismic indices measurement, providing masses, radii and evolution stages for half a million solar-type pulsators (subgiants and red giants), in our galactic neighborhood and allowing unprecedented stellar population studies.

Dedicated tip–tilt loops are commonly implemented on adaptive optics (AO) systems. In addition, a number of recent high-performance systems feature tip–tilt controllers that are more efficient than the integral action controller. In this context, linear–quadratic–Gaussian (LQG) tip–tilt regulators based on stochastic models identified from AO telemetry have demonstrated their capacity to effectively compensate for the cumulated effects of atmospheric disturbance, windshake and vibrations. These tip–tilt LQG regulators can also be periodically retuned during AO operations, thus allowing to track changes in the disturbances' temporal dynamics. This paper investigates the potential benefit of extending the number of low-order modes to be controlled using models identified from AO telemetry. The global stochastic dynamical model of a chosen number of turbulent low-order modes is identified through data-driven modelling from wavefront sensor measurements. The remaining higher modes are modelled using priors with autoregressive models of order 2. The loop is then globally controlled using the optimal LQG regulator build from all these models. Our control strategy allows for combining a dedicated tip–tilt loop with a deformable mirror that corrects for the remaining low-order modes and for the higher orders altogether, without resorting to mode decoupling. Performance results are obtained through evaluation of the Strehl ratio computed on H -band images from the scientific camera, or in replay mode using on-sky AO telemetry recorded in 2019 July on the CANARY instrument. [ABSTRACT FROM AUTHOR]