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We present a concept for visible near-diffraction limited lucky imaging with full-sky laser assisted adaptive optics.Simulation results are given, along with first on-sky measurements taken with the CANARY AO system on theWilliam Herschel Telescope, and extension to ELT scales.We also present a study of readout noise in EMCCD and sCMOS detectors, with findings that are perhapssurprising when compared with naive models of sCMOS noise. We discuss the relative trade-offs of these detectorsfor ELT-scale AO and lucky imaging.Finally we introduce the concept of real-time simulation, necessary for integration and verification of ELT-scale AO systems, and provide details of the system developed for CANARY.

We present a concept for visible near-diffraction limited lucky imaging with full-sky laser assisted adaptive optics.Simulation results are given, along with first on-sky measurements taken with the CANARY AO system on theWilliam Herschel Telescope, and extension to ELT scales.We also present a study of readout noise in EMCCD and sCMOS detectors, with findings that are perhapssurprising when compared with naive models of sCMOS noise. We discuss the relative trade-offs of these detectorsfor ELT-scale AO and lucky imaging.Finally we introduce the concept of real-time simulation, necessary for integration and verification of ELT-scale AO systems, and provide details of the system developed for CANARY.

The high control frequency required of planned E-ELT adaptive optics modules (from several hundreds of Hz tothousands and typically in the region of 500 Hz for first light E-ELT instruments such as HARMONI), along withthe high number of actuators, leads to very demanding computational needs for the real-time AO control (RTC)systems. The number of actuators, proportional the total area of the telescope primary mirror, will range fromseveral thousands to tens of thousands (typically 4-6 thousand for first light E-ELT instruments). TraditionalRTC architectures based on CPU only technologies are typically unable to achieve the required performancein a cost-effective and maintainable manner. Alternative hardware such as many-core hardware acceleratorsneed to be considered to deliver the computational power. These many-core processors offering a highly parallelenvironment, have the potential of coping with the high computational load and of accelerating parts of the AOcontrol loop. AO systems for the E-ELT however, also put heavy constrains on acceptable levels of jitter andlatency.In this paper, we investigate novel hardware that has the potential to accelerate wavefront reconstruction andwavefront pre-processing, respectively the Intel Xeon Phi and the TILERA TILE-Gx processors. We present adetailed performance analysis putting an emphasis on execution time, jitter (i.e. variation in execution time)and outliers (i.e. results significantly apart from mean). Results are explored both for specific first light E-ELTinstruments and, to stay as general as possible and fully appreciate scalability issues, for a much wider range ofAO system sizes. The paper also addresses anticipated near future hardware developments and examines theirsuitability for the E-ELT.

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.

MOSAIC is the proposed multiple object spectrograph for the E-ELT that will eventually combine two AO observing modes within a single instrument. MOSAIC will contain up to 20 open-loop multiple object AO channels feeding NIR IFUs in addition to up to 200 seeing-limited (or GLAO corrected) VIS – NIR fibre pickoffs. Wavefront tomography will be implemented using a combination of LGS and a few high-order NGS distributed across the field with the wavefront correction applied in a split open/closed loop configuration. MOSAIC will be the only E-ELT instrument planned that can utilize the full 10 arcminute diameter field of view, enabling highly efficient observing modes for this workhorse instrument. Use of the full E-ELT field inevitably requires a closer integration between the telescope control system and the instrument AO systems, however this can bring several potential benefits to overall system performance. Here we present the initial design concept and baseline performance of the MOSAIC instrument and AO system(s) taking advantage of the CANARY on-sky results and inheriting from the previous Phase A study of EAGLE. Finally, we will highlight areas of system performance and calibration that will require further analysis and trade-off during the course of the upcoming Phase A study.

We report the progress of the Canary High-Order Upgrade (CHOUGH) addition to the CANARY AO experimentat the 4.2m WHT telescope, ORM, La Palma. While CANARY has been developed to investigate severaltomographic congurations relevant to the E-ELT, it also has the ability to host guest AO instruments andprovide them with relevant infrastructure. CHOUGH is a self-contained AO bench that integrates into CANARY,via an external feed of light, to provide a Strehl 0:5 in the visible. Within CANARY, CHOUGH picks o lightafter a 240-actuator deformable mirror and delivers the on-axis beam into the internal relay which feeds varioussub-systems. These are include pick-o optics, a ADC, and 1k-actuator DM, all of which are part of an internalrelay to three instruments: a spatially-ltered SH WFS, a calibration interferometer, and a narrow-eld imagingcamera. As CHOUGH is constructed on a separate breadboard, the components are self-contained and can beintegrated and operated separately from CANARY. In this paper the progress on the design, procurement, andperformance of the CHOUGH sub-systems and the experiment as a whole is given. Attention is given to thealgorithms that will be used and the control methods that will be utilized on-sky. The modular nature of thedesign leads to potential upgrade paths and a brief discussion is made of new directions of on-sky research thatcould be carried out with replacement sub-systems and new instrumentation.

The requirements on the real-time control systems for ELT instruments strongly encourage an investigation of newly emerging hardware and an assessment of its suitability for the job. We have implemented the full AO data processing pipeline on Graphics Processing Units (GPUs), within the framework of Durham AO Real-time Controller (DARC). The pixel data are copied from the CPU memory to the GPU memory. On the GPU, the data are processed and the DM commands are copied back to the CPU. For a system of 80x80 subapertures, the highest rate achieved on a single GPU is 550 frames per second. When running on two or more GPUs, the kernel launching time limits the increase in frame rate. We have also implemented the correlation centroiding algorithm, which - when used - reduces the frame rate by about a factor of two.

MOSAIC is the proposed multiple object spectrograph for the E-ELT that will eventually combine two AO observing modes within a single instrument. MOSAIC will contain up to 20 open-loop multiple object AO channels feeding NIR IFUs in addition to up to 200 seeing-limited (or GLAO corrected) VIS – NIR fibre pickoffs. Wavefront tomography will be implemented using a combination of LGS and a few high-order NGS distributed across the field with the wavefront correction applied in a split open/closed loop configuration. MOSAIC will be the only E-ELT instrument planned that can utilize the full 10 arcminute diameter field of view, enabling highly efficient observing modes for this workhorse instrument. Use of the full E-ELT field inevitably requires a closer integration between the telescope control system and the instrument AO systems, however this can bring several potential benefits to overall system performance. Here we present the initial design concept and baseline performance of the MOSAIC instrument and AO system(s) taking advantage of the CANARY on-sky results and inheriting from the previous Phase A study of EAGLE. Finally, we will highlight areas of system performance and calibration that will require further analysis and trade-off during the course of the upcoming Phase A study.

We report the progress of the Canary High-Order Upgrade (CHOUGH) addition to the CANARY AO experimentat the 4.2m WHT telescope, ORM, La Palma. While CANARY has been developed to investigate severaltomographic congurations relevant to the E-ELT, it also has the ability to host guest AO instruments andprovide them with relevant infrastructure. CHOUGH is a self-contained AO bench that integrates into CANARY,via an external feed of light, to provide a Strehl 0:5 in the visible. Within CANARY, CHOUGH picks o lightafter a 240-actuator deformable mirror and delivers the on-axis beam into the internal relay which feeds varioussub-systems. These are include pick-o optics, a ADC, and 1k-actuator DM, all of which are part of an internalrelay to three instruments: a spatially-ltered SH WFS, a calibration interferometer, and a narrow-eld imagingcamera. As CHOUGH is constructed on a separate breadboard, the components are self-contained and can beintegrated and operated separately from CANARY. In this paper the progress on the design, procurement, andperformance of the CHOUGH sub-systems and the experiment as a whole is given. Attention is given to thealgorithms that will be used and the control methods that will be utilized on-sky. The modular nature of thedesign leads to potential upgrade paths and a brief discussion is made of new directions of on-sky research thatcould be carried out with replacement sub-systems and new instrumentation.

The requirements on the real-time control systems for ELT instruments strongly encourage an investigation of newly emerging hardware and an assessment of its suitability for the job. We have implemented the full AO data processing pipeline on Graphics Processing Units (GPUs), within the framework of Durham AO Real-time Controller (DARC). The pixel data are copied from the CPU memory to the GPU memory. On the GPU, the data are processed and the DM commands are copied back to the CPU. For a system of 80x80 subapertures, the highest rate achieved on a single GPU is 550 frames per second. When running on two or more GPUs, the kernel launching time limits the increase in frame rate. We have also implemented the correlation centroiding algorithm, which - when used - reduces the frame rate by about a factor of two.

The high control frequency required of planned E-ELT adaptive optics modules (from several hundreds of Hz tothousands and typically in the region of 500 Hz for first light E-ELT instruments such as HARMONI), along withthe high number of actuators, leads to very demanding computational needs for the real-time AO control (RTC)systems. The number of actuators, proportional the total area of the telescope primary mirror, will range fromseveral thousands to tens of thousands (typically 4-6 thousand for first light E-ELT instruments). TraditionalRTC architectures based on CPU only technologies are typically unable to achieve the required performancein a cost-effective and maintainable manner. Alternative hardware such as many-core hardware acceleratorsneed to be considered to deliver the computational power. These many-core processors offering a highly parallelenvironment, have the potential of coping with the high computational load and of accelerating parts of the AOcontrol loop. AO systems for the E-ELT however, also put heavy constrains on acceptable levels of jitter andlatency.In this paper, we investigate novel hardware that has the potential to accelerate wavefront reconstruction andwavefront pre-processing, respectively the Intel Xeon Phi and the TILERA TILE-Gx processors. We present adetailed performance analysis putting an emphasis on execution time, jitter (i.e. variation in execution time)and outliers (i.e. results significantly apart from mean). Results are explored both for specific first light E-ELTinstruments and, to stay as general as possible and fully appreciate scalability issues, for a much wider range ofAO system sizes. The paper also addresses anticipated near future hardware developments and examines theirsuitability for the E-ELT.

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.