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One of the primary scientific limitations of adaptive optics (AO) has been the incomplete knowledge of the point spread function (PSF), which has made it difficult to use AO for accurate photometry and astrometry in both crowded and sparse fields, for extracting intrinsic morphologies and spatially resolved kinematics, and for detecting faint sources in the presence of brighter sources. To address this we initiated a program to determine and demonstrate PSF determination for science observations obtained with Keck AO. This paper aims to give a broad view of the progress achieved in implementing this capability for Keck AO science observations.The concept and the implementation are briefly described. The design and development of prototype operational tools for automated PSF reconstruction is presented in detail. On-sky performance of the technique is discussed by comparing the reconstructed PSFs to the NIRC2 science camera’s PSFs. The PSF algorithm development for this program is presented in this conference in a separate paper (Jolissaint et al. 2016).

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.

The advent of a new generation of Wide Field AO (WFAO) systems marks the beginning of a new era in high spatial resolution imaging. By using multiple Laser Guide Stars, WFAO significantly increases the field of view of the AOcorrected images, and the fraction of the sky that can benefit from such correction. The newly commissioned Gemini South Multi-Conjugate Adaptive Optics System (GeMS) combined with the infrared camera GSAOI is delivering almost di raction-limited images over a field of 2 arc-minutes across. In this paper, we first present recent observations of the young star-forming region N159W located in the Large Magellanic Cloud. We obtained deep JHKs images from the GeMS/ GSAOI instrument and developed reduction tools, in order to photometrically study the properties of the stellar members of the cluster and to bring new elements to our understanding of the process of massive star formation. However, despite the excellent performance of the GeMS/ GSAOI system, some variable residues are still limiting the correction quality over the field. In particular, GSAOI is severely a ected by distortion that can strongly degrade the resolution when combining multiple frames and can consequently reduce the sensitivity. The accuracy of the distortion correction of an instrument is critical for its use for high- precision astrometry and photometry. In a second part of this paper, we investigate an optimal way to correct for the distortion following an inverse problem approach. The formalism as well as first simulation results are presented.

The advent of a new generation of Wide Field AO (WFAO) systems marks the beginning of a new era in high spatial resolution imaging. By using multiple Laser Guide Stars, WFAO significantly increases the field of view of the AOcorrected images, and the fraction of the sky that can benefit from such correction. The newly commissioned Gemini South Multi-Conjugate Adaptive Optics System (GeMS) combined with the infrared camera GSAOI is delivering almost di raction-limited images over a field of 2 arc-minutes across. In this paper, we first present recent observations of the young star-forming region N159W located in the Large Magellanic Cloud. We obtained deep JHKs images from the GeMS/ GSAOI instrument and developed reduction tools, in order to photometrically study the properties of the stellar members of the cluster and to bring new elements to our understanding of the process of massive star formation. However, despite the excellent performance of the GeMS/ GSAOI system, some variable residues are still limiting the correction quality over the field. In particular, GSAOI is severely a ected by distortion that can strongly degrade the resolution when combining multiple frames and can consequently reduce the sensitivity. The accuracy of the distortion correction of an instrument is critical for its use for high- precision astrometry and photometry. In a second part of this paper, we investigate an optimal way to correct for the distortion following an inverse problem approach. The formalism as well as first simulation results are presented.

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.

One of the primary scientific limitations of adaptive optics (AO) has been the incomplete knowledge of the point spread function (PSF), which has made it difficult to use AO for accurate photometry and astrometry in both crowded and sparse fields, for extracting intrinsic morphologies and spatially resolved kinematics, and for detecting faint sources in the presence of brighter sources. To address this we initiated a program to determine and demonstrate PSF determination for science observations obtained with Keck AO. This paper aims to give a broad view of the progress achieved in implementing this capability for Keck AO science observations.The concept and the implementation are briefly described. The design and development of prototype operational tools for automated PSF reconstruction is presented in detail. On-sky performance of the technique is discussed by comparing the reconstructed PSFs to the NIRC2 science camera’s PSFs. The PSF algorithm development for this program is presented in this conference in a separate paper (Jolissaint et al. 2016).

ARGOS is the laser guide star facility of the Large Binocular Telescope (LBT). It implements a Rayleigh Laser Guide Star system that provides Ground Layer Adaptive Optics (GLAO) correction for the LUCIs, the 2 wide- field near-infrared imagers and multi-object spectrographs installed on the 2 eyes of LBT. In this paper we describe how LBT’s adaptive optics operations have been tailored to ARGOS’s use cases based on the experience developed during over the ARGOS commissioning. We focus on all the aspects that are influenced by the use of the Laser Guide Stars, from collimation to acquisition and LGS guiding and we details the sequences to start, pause and resume the adaptive correction.

The laser guide star (LGS) adaptive optics (AO) system on the Keck II telescope has been upgraded with a Center Launch Laser System (CLS) and a next generation laser (NGL; i.e. a TOPTICA/MPBC laser) is being implemented. The purpose of the CLS upgrade is to improve the performance of the existing Keck II LGS AO system by reducing the perspective elongation of the LGS as seen by the AO wavefront sensor and hence the measurement error, one of the largest terms in the current error budget. This performance improvement is achieved by projecting the laser from behind the Keck telescope’s secondary mirror instead of from the side of the Keck telescope. The purpose of the NGL upgrade is to increase the laser return and improve laser operability for science operation. The higher return from the NGL would open up new possibilities for further AO upgrades such as a laser asterism to reduce the focal anisoplanatism, and to increase the wavefront sensor (WFS) sampling rate to reduce the bandwidth error in addition to reducing the measurement error.The CLS transitioned to science operation in June 2015. The NGL with the CLS had first light on Dec. 1, 2015 and is being optimized to support transitioning to science operations in April 2016. This paper provides an overview of the design, implementation and on-sky performance of the new launch system and laser. The results are discussed in the context of AO for extremely large telescopes.

We present in this paper preliminary simulation results aimed at validating the GMT piston control strategy. Wewill in particular consider an observing mode in which an Adaptive Optics (AO) system is providing fast on-axisWF correction with the Adaptive Secondary Mirror (ASM), while the phasing system using multiple SegmentPiston Sensors (SPS) makes sure that the seven GMT segments remain phased. Simulations have been performedwith the Dynamic Optical Simulation (DOS) tool developed at the GMT Project Oce, which integrates theoptical and mechanical models of GMT. DOS fast ray-tracing capabilities allows us to properly simulate theeect of eld-dependent aberrations, and in particular, the so-called Field Dependent Segment Piston (FDSP)mode arising when a segment tilt on M1 is compensated on-axis by a segment tilt on M2. We will show thatwhen using an asterism of SPS, our scheme can properly control both segment piston and the FDSP mode.

NFIRAOS, the first light AO system for the Thirty Meter Telescope, will include a natural guide star (NGS) pyramidwave-front sensor (PWFS). This WFS will have two functions: (i) when there is a bright enough NGS within the sciencefield and the lasers are turned off, the PWFS will act as the fast high order WFS driving the SCAO loop (e.g. for highcontrastimaging); and (ii) when the lasers are in use and the system operates in MCAO mode, the PWFS will act as aslow truth WFS (e.g. to measure drifts in the structure of the sodium layer). The decision to select a PWFS instead of amore conventional Shack-Hartmann WFS (SHWFS) is the outcome of a detailed trade study. In this paper, wesummarize the results of this trade study. These include extensive simulation work, which shows that, in the expectedoperating conditions of NFIRAOS, the PWFS will bring significant performance improvements, including higher Strehlratio, higher limiting magnitude and lower residual speckle levels for high contrast imaging, even when the system hasto correct for significant levels of non-common path aberrations. Our simulation results also provides new insights onthe properties of the PWFSs. We also report on opto-mechanical design work, which shows that, with the PWFS, the twofunctions (i) and (ii) can actually be combined into a single optical path, thus reducing the complexity in terms ofnumber of mechanisms and optical elements. Finally, we discuss the impacts of switching to a PWFS on the otheralready designed NFIRAOS sub-systems (e.g. the real-time computer), which we have found to be very modest.