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Multiple sites within Germany operate human MRI systems with magnetic fields either at 7 Tesla or 9.4 Tesla. In 2013, these sites formed a network to facilitate and harmonize the research being conducted at the different sites and make this technology available to a larger community of researchers and clinicians not only within Germany, but also worldwide. The German Ultrahigh Field Imaging (GUFI) network has defined a strategic goal to establish a 14 Tesla whole-body human MRI system as a national research resource in Germany as the next progression in magnetic field strength. This paper summarizes the history of this initiative, the current status, the motivation for pursuing MR imaging and spectroscopy at such a high magnetic field strength, and the technical and funding challenges involved. It focuses on the scientific and science policy process from the perspective in Germany, and is not intended to be a comprehensive systematic review of the benefits and technical challenges of higher field strengths.

Laser guide stars have been proposed to overcome a widely recognized limitation of adaptive optics: the need for bright reference sources for wavefront sensing nearby the scientific field of interest. The laser guide stars foreseen for the future Extremely Large Telescopes are based on the resonant back-scattering of a laser beam by the Sodium atoms concentrated in a ∼13 km thick layer at about 90 km above the ground. Such an artificial source, observed from a position laterally offset from the laser projector, appears elongated due to the finite thickness of the Sodium layer: on a 40-m class telescope with laser projector located on the primary mirror edge the image elongation may exceed 13 arcsec. In a Shack–Hartmann wavefront sensor, the elongated spots require the use of large detectors to avoid spot truncation and impose demanding requirements in terms of photon flux return with respect to smaller telescopes. We propose an alternative wavefront sensor concept intrinsically insensitive to the spot elongation, measuring the local wavefront slope in the direction orthogonal to the elongation itself; the full 2D slope measurements are retrieved by combining the signals from different laser guide stars, projected from different positions at the edge of the telescope. The performance of the new wavefront sensor is analysed in the framework of a ground-layer adaptive optics application. A possible extension to multiconjugate adaptive optics is also qualitatively described.

Prolonged human-crewed missions on the Moon are foreseen as a gateway for Mars and asteroid colonisation in the next decades. Health risks related to long-time permanence in space have been partially investigated. Hazards due to airborne biological contaminants represent a relevant problem in space missions. A possible way to perform pathogens’ inactivation is by employing the shortest wavelength range of Solar ultraviolet radiation, the so-called germicidal range. On Earth, it is totally absorbed by the atmosphere and does not reach the surface. In space, such Ultraviolet solar component is present and effective germicidal irradiation for airborne pathogens’ inactivation can be achieved inside habitable outposts through a combination of highly reflective internal coating and optimised geometry of the air ducts. The Solar Ultraviolet Light Collector for Germicidal Irradiation on the Moon is a project whose aim is to collect Ultraviolet solar radiation and use it as a source to disinfect the re-circulating air of the human outposts. The most favourable positions where to place these collectors are over the peaks at the Moon’s poles, which have the peculiarity of being exposed to solar radiation most of the time. On August 2022, NASA communicated to have identified 13 candidate landing regions near the lunar South Pole for Artemis missions. Another advantage of the Moon is its low inclination to the ecliptic, which maintains the Sun’s apparent altitude inside a reduced angular range. For this reason, Ultraviolet solar radiation can be collected through a simplified Sun’s tracking collector or even a static collector and used to disinfect the recycled air. Fluid-dynamic and optical simulations have been performed to support the proposed idea. The expected inactivation rates for some airborne pathogens, either common or found on the International Space Station, are reported and compared with the proposed device efficiency. The results show that it is possible to use Ultraviolet solar radiation directly for air disinfection inside the lunar outposts and deliver a healthy living environment to the astronauts.

The crossed-sine wavefront sensor (WFS) is a pupil plane wavefront sensor that measures the first derivatives of the wavefront. It is made by three main components: a gradient transmission filter (GTF) built from a product of sine functions rotated by 45 degrees around the optical axis, a 2x2 mini-lens array (MLA) at the focus of the tested optical system and a detector array located on a plane conjugated to the pupil. The basic principle consists in acquiring four pupil images simultaneously, each image being observed from different points located behind the GTF. After the simulation work which demonstrated the wavefront reconstruction capability, we are now in the phase of implementation of the prototype in the lab. The crossed-sine WFS could achieve a simultaneous high spatial resolution at the pupil of the tested optics and absolute measurement accuracy comparable to that attained by laser-interferometers. In this paper we introduce seven customized phase masks and make measurements of them.First tests and resultsare demonstrated, based on which we explore the performance of our crossed-sine WFS and make comparisons with that of the laser-interferomete

In this article we address the question of whether age stereotypes impact cognitive performance in a consumer behavioral context. We assume that in consumer decision-making contexts, the elderly are affected by negative (vs. positive) age stereotypes, leading to less self-efficacy and thus a decrease in cognitive performance. We extend prior research by also asking whether perceived time pressure can reinforce the effects of age stereotypes on the elderly’s self-efficacy, which can in turn influence cognitive performance. The results of our experiment reveal that priming with negative (vs. positive) stereotypes leads to decreased cognitive performance among the elderly. This relationship is mediated by self-efficacy. Furthermore, self-perception of aging serves as a mediator for the effect of self-efficacy and cognitive performance. The effect of self-efficacy on cognitive performance is reinforced when consumers feel that they are under time pressure. The results of our investigation have importa...

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Ariel, the Atmospheric Remote-sensing Infrared Exoplanet Large-survey, was adopted as the fourth medium-class mission in ESA's Cosmic Vision programme to be launched in 2029. During its 4-year mission, Ariel will study what exoplanets are made of, how they formed and how they evolve, by surveying a diverse sample of about 1000 extrasolar planets, simultaneously in visible and infrared wavelengths. It is the first mission dedicated to measuring the chemical composition and thermal structures of hundreds of transiting exoplanets, enabling planetary science far beyond the boundaries of the Solar System. The payload consists of an off-axis Cassegrain telescope (primary mirror 1100 mm x 730 mm ellipse) and two separate instruments (FGS and AIRS) covering simultaneously 0.5-7.8 micron spectral range. The satellite is best placed into an L2 orbit to maximise the thermal stability and the field of regard. The payload module is passively cooled via a series of V-Groove radiators; the detectors for the AIRS are the only items that require active cooling via an active Ne JT cooler. The Ariel payload is developed by a consortium of more than 50 institutes from 16 ESA countries, which include the UK, France, Italy, Belgium, Poland, Spain, Austria, Denmark, Ireland, Portugal, Czech Republic, Hungary, the Netherlands, Sweden, Norway, Estonia, and a NASA contribution., Comment: Ariel Definition Study Report, 147 pages. Reviewed by ESA Science Advisory Structure in November 2020. Original document available at: https://www.cosmos.esa.int/documents/1783156/3267291/Ariel_RedBook_Nov2020.pdf/

Multi-conjugated adaptive optics (MCAO) is essential for performing astrometry with the Extremely Large Telescope (ELT). Unlike most of the 8-m class telescopes, the ELT will be a fully adaptive telescope, and a significant portion of the adaptive optics (AO) dynamic range will be depleted by the correction and stabilization of the telescope aberrations and instabilities. MCAO systems are of particular interest for ground-based astrometry since they stabilize the low-order field distortions and transient plate scale instabilities, which originate from the telescope and in the instrument. All instruments have several optical elements relatively far away from the pupil that can potentially challenge the astrometric precision of the observations with their residual mid-spatial frequencies errors. Using a combined simulation of ray tracing and AO numerical codes, we assess the impact of these systematic errors at different field-of-view (FoV) scales and fitting scenarios. The distortions have been assessed at different sky position angles (PA) and indicate that over large FoVs only small PA ranges (±1 deg to 3 deg) are accessible with astrometric residuals ≤50 μas. A full compliance with the astrometric requirement, at any PA, is achievable for 2 arc sec2 FoV patches already with a third-order polynomial. The natural partition of the optical system into three segments, i.e., the ELT, the MAORY MCAO module, and the MICADO instrument, resembles a splitting of the astrometric problem into the three subsystems that are characterized by different distortion amplitudes and calibration strategies. The result is a family portrait of the different optical segments with their specifications, dynamic motions, conjugation height, and AO correctability, leading to tracing their role in the bigger puzzle of the 50-μas as astrometric endeavor.

The Starfinder code has been one of the first attempts to face with the typical adaptive optics structured Point Spread Function (PSF) in dense star fields to accomplish astrometric and photometric analysis. The last release of the software can also handle a variation of the PSF across the Field of View (FoV). The PSF can be either extracted numerically from the brightest stars in the science field or computed externally and provided as an input in the form of a single image or a cube of images. This feature makes this software suitable to work with PSF models obtained by PSF reconstruction techniques. Starfinder also accepts as an input a user-defined parametric model and a variable pointing the PSF auxiliary data required by the parametric-model. This variable might containing also information about the spatial variation across the FoV. In this paper we describe the next release of Starfinder reporting also some examples and we give the recipe to use the tool for variable PSF.

The crossed-sine wavefront sensor (WFS), which is based on a gradient transmission filter (GTF) and a 2´2 minilens array (MLA), enables simultaneous achromatic imaging at a high spatial resolution. The GTF is formed by four circular sub-apertures with the crossed-sine pattern for spatial filtering, producing four initial images. The 2´2 MLA, which is placed on the image plane of the optical system, is adjusted to transfer the image of the exit pupil onto the detector array. In this paper, we present the design of the GTF and MLA, and some preliminary experimental tests of the crossed-sine WFS system. For the first prototype, a spatial light modulator (SLM) is utilized to simulate the GTF functions, and an achromat is applied to transfers the pupil images instead of the MLA. The pupil image and the wavefront error have been obtained. This crossed-sine WFS imaging system is user-friendly and will serve a large range of high throughput applications in astronomy, biomedicine and metrology.

MCAO is essential to perform astrometry with the Extremely Large Telescope (ELT). Differently from the 8m class telescopes, the ELT will be a fully adaptive telescope, and a significant portion of the Adaptive Optics (AO) dynamic range will be absorbed by the correction and stabilization of the telescope aberrations and instabilities. Of particular interest for the ground-based astrometry is the use of Multi-Conjugated AO systems that allow to stabilize the low order field distortions against the transient plate scale instabilities of different origin occurring at the telescope and in the instrument. The instruments have several optical elements relatively far away from the pupil that can potentially challenge the astrometric precision of the observations with their residual mid-spatial frequencies errors. Using a combined simulation of ray tracing and AO numerical codes we assess the impact of these systematic errors at different field of view scales and fitting scenarios. The distortions have been assessed at different sky Position Angles (PA) and indicate that over large field of views only small PA ranges (±1°-3°) are accessible with astrometric residuals 50 µas. A full compliance, at any PA is achievable for 2 arcsec2 FoV patches already with a 3rd order polynomial. The natural partition of the optical system in three segments, ELT-MAORY-MICADO, respectively telescope, MCAO module and instrument, resembles also a splitting of the astrometric problem in the three subsystems that are characterized by different distortion amplitudes and calibration strategies. The result is a family portrait of the different optical segments with their prescription, dynamic motions, conjugation height and AO correctability, leading to trace their role in the bigger puzzle of the 50 μas astrometric endeavor.

International audience; Determining the PSF remains a key challenge for post adaptive-optics (AO) observations regarding the spatial, temporal and spectral variabilities of the AO PSF, as well as itx complex structure. This paper aims to provide a non-exhaustive but classified list of techniques and references that address this issue of PSF determination, with a particular scope on PSF reconstruction, or more generally pupil-plane-based approaches. We have compiled a large amount of references to synthesize the main messages and kept them at a top level. We also present applications of PSF reconstruction/models to post-processing, more especially PSF-fitting and deconvolution for which there is a fast progress in the community.

We present a novel analysis of a young star cluster in the Large Magellanic cloud, R136-like, as seen by the Extremely Large Telescope (ELT). The main aim of this study is to quantify precision and accuracy of stellar proper motion measurements in crowded field when using an ELT working at its diffraction limit. This can serve as a reference study for future development of ELT scientific cases. In particular, we investigate our future ability to detect the dynamical signature of intermediate-mass black holes (IMBHs) with mass ∼104 M⊙ through detailed measurements of stellar proper motions. We have simulated two N-body dynamical cluster models with and without an IMBH. For each model, we have chosen two snapshots temporally spaced by 5 yr. Stellar fluxes in IJHK filters and star positions have been used to create ELT mock images for both single- and multiconjugate adaptive optics observing modes following the requierements given by ESO technical specifications for the first light imager. These images have been analysed using a classical software for seeing-limited data reduction, daophot/allstar. We make accurate photometry till the very faint pre-main-sequence stars, i.e. depending on the adaptive optics (AO) mode, magnitudes down to K ∼ 24 mag (single-conjugate AO) or K ∼ 22 mag (multiconjugate AO) in a total integration time of 20 min on target. Although daophot suite of programs is not devoted to precise astrometry, the astrometric accuracy is impressive, reaching few μas yr−1 or km s−1. In these assumptions, we are able to detect the IMBH signature at the centre of the cluster.

The new class of large telescopes, as the future ELT, are designed to work with Laser Guide Star (LGS) tuned to a resonance of atmosphere sodium atoms. This wavefront sensing technique presents complex issues for an application to big telescopes due to many reasons mainly linked to the finite distance of the LGS, the launching angle, Tip-tilt indetermination and focus anisoplanatism. The implementation of a laboratory Prototype for LGS wavefront sensor (WFS) at the beginning of the phase study of MAORY, the Multi-conjugate Adaptive Optics RelaY for the ELT first light, has been indispensable to investigate specific mitigation strategies to the LGS WFS issues. This paper shows the test results of LGS WFS Prototype under different working conditions. The accuracy within which the LGS images are generated on the Shack-Hartmann (SH) WFS has been cross-checked with the MAORY simulation code. The experiments show the effect of noise on the centroiding precision, the impact of LGS image truncation on the wavefront sensing accuracy as well as the temporal evolution of sodium density profile and LGS image under-sampling.

MAO (MAORY Adaptive Optics) is the a developed numerical simulation tool for adaptive optics. It was created especially to simulate the performance of the MAORY MCAO module of the Extremely Large Telescope. It is a full end-to-end Monte-Carlo code able to perform different flavors of adaptive optics simulation. We used it to investigate the performance of a the MAORY and some specific issue related to calibration, acquisition and operation strategies. As, MAORY, MAO will implement Multi-conjugate Adaptive Optics combining Laser Guide Stars (LGS) and Natural Guide Stars (NGS) measurements. The implementation of the reference truth WFS completes the scheme. The simulation tool implements the various aspect of the MAORY in an end to end fashion. The code has been developed using IDL and use libraries in C++ and CUDA for efficiency improvements. Here we recall the code architecture, we describe the modeled instrument components and the control strategies implemented in the code.

MAORY is one of the approved instruments for the European Extremely Large Telescope. It is an adaptive optics module, enabling high-angular resolution observations in the near infrared by real-time compensation of the wavefront distortions due to atmospheric turbulence and other disturbances such as wind action on the telescope. An overview of the instrument design is given in this paper.

MAORY will be the multi-adaptive optics module feeding the high resolution camera and spectrograph MICADO at the Extremely Large Telescope (ELT) first light. In order to ensure high and homogeneous image quality over the MICADO field of view and high sky coverage, the baseline is to operate wavefront sensing using six Sodium Laser Guide Stars. The Laser Guide Star Wavefront Sensor (LGS WFS) is the MAORY sub-system devoted to real-time measurement of the high order wavefront distortions. In this paper we describe the MAORY LGS WFS current design, including opto-mechanics, trade-offs and possible future improvements.

MAORY is the ELT-MCAO system providing first-light wide-field correction for the near infrared imager and spectrograph MICADO. This paper provides an overview of the systems engineering processes and tools implemented to MAORY project during preliminary design phase and it illustrates, with some practical examples, the role of MAORY technical budgets to derive requirements on subsystems. One of the critical activities in systems engineering is the requirements managing. In line with this, the MAORY team devotes a significant effort to this activity, which follows a well-established process. This involves the MAORY requirements break-down to subsystems level and from here down to subsystems procurements specifications. This paper also presents an overview of the MAORY Technical Budgets. One task of the System Engineering is to manage the technical budgets at system level combining the contributors at subsystems level to meet the overall requirements.

MAORY is the Multi-conjugate Adaptive Optics module for the Extremely Large Telescope and it will be located on the Nasmyth platform of the telescope to feed scientific instruments. MAORY will re-image the telescope focal plane providing multi-conjugate adaptive optics correction of the wavefront distortion induced by the atmosphere. The system is based on six laser guide stars and three natural guide stars for sensing the wavefront distortion and three deformable mirrors for correcting it. We will show the current status of the preliminary design of the Real Time Computer in charge of carrying out all the calculations based on the measurements of the guide stars wavefront sensors. The hard real time (primary) loops are in charge of controlling the deformable mirrors and the lasers jitter compensation while the soft real- time (secondary) loops are in charge of updating the primary loops parameters as well as measuring or estimating the atmospheric parameters and the system performance. Telemetry data management/recording and calibration are the other tasks carried out by the real time computer.

The next generation of large aperture ground based telescopes will offer the opportunity to perform accurate stellar photometry in very crowded fields. This future capability will allow one to study in detail the stellar population in distant galaxies. In this paper we explore the effect of photometric errors on the stellar metallicity distribution derived from the color distribution of the Red Giant Branch stars in the central regions of galaxies at the distance of the Virgo cluster. We focus on the analysis of the Color-Magnitude Diagrams at different radii in a typical giant Elliptical galaxy obtained from synthetic data constructed to exemplify observations of the European Extremely Large Telescope. The simulations adopt the specifications of the first light high resolution imager MICADO and the expected performance of the Multi-Conjugate Adaptive Optics Module MAORY. We find that the foreseen photometric accuracy allows us to recover the shape of the metallicity distribution with a resolution $\lesssim 0.4$ dex in the inner regions ($\mu_{\rm B}$ = 20.5 mag arcsec$^{-2}$) and $\simeq 0.2$ dex in regions with $\mu_{\rm B}$ = 21.6 mag arcsec$^{-2}$, that corresponds to approximately half of the effective radius for a typical giant elliptical in Virgo. At the effective radius ($\mu_{\rm B} \simeq 23$ mag arcsec$^{-2}$), the metallicity distribution is recovered with a resolution of $\simeq 0.1$ dex. It will thus be possible to study in detail the metallicity gradient of the stellar population over (almost) the whole extension of galaxies in Virgo. We also evaluate the impact of moderate degradations of the Point Spread Function from the assumed optimal conditions and find similar results, showing that this science case is robust.

We overview the current status of photometric analyses of images collected with Multi Conjugate Adaptive Optics (MCAO) at 8-10m class telescopes that operated, or are operating, on sky. Particular attention will be payed to resolved stellar population studies. Stars in crowded stellar systems, such as globular clusters or in nearby galaxies, are ideal test particles to test AO performance. We will focus the discussion on photometric precision and accuracy reached nowadays. We briefly describe our project on stellar photometry and astrometry of Galactic globular clusters using images taken with GeMS at the Gemini South telescope. We also present the photometry performed with DAOPHOT suite of programs into the crowded regions of these globulars reaching very faint limiting magnitudes Ks ~21.5 mag on moderately large fields of view (~1.5 arcmin squared). We highlight the need for new algorithms to improve the modeling of the complex variation of the Point Spread Function across the field of view. Finally, we outline the role that large samples of stellar standards plays in providing a detailed description of the MCAO performance and in precise and accurate colour{magnitude diagrams., 17 pages, 12 figures, SPIE 2016

MAORY will be the multi-conjugate adaptive optics module for the E-ELT first light. The baseline is to operate wavefront sensing using 6 Sodium Laser Guide Stars and 3 Natural Guide Stars to solve intrinsic limitations of artificial beacons and to mitigate the impact of the sodium layer structure and variability. In particular, some critical components of MAORY require to be designed and dimensioned in order to reduce the spurious effects arising from the Sodium Layer density distribution and variation. The MAORY end-to-end simulation code has been designed to accurately model the Laser Guide Star image in the Shack-Hartmann wavefront sensor sub-apertures and to allow sodium profile temporal evolution. The fidelity with which the simulation code translates the sodium profiles in Laser Guide Star images at the wavefront sensor focal plane has been verified using a laboratory Prototype.

MICADO is the E-ELT first-light imager, working at the diffraction limit in the near-infrared. Multi-conjugate adaptive optics (MCAO) will be the primary AO mode of MICADO, driving the design of the instrument. It will be provided by MAORY, the E-ELT first-light AO module. MICADO will also come with a SCAO capability, jointly developed by MICADO and MAORY. SCAO will be the first AO mode to be tested at the telescope, in a phased approach of AO integration at the E-ELT. We present in the following the MICADO-MAORY SCAO specifications, the current SCAO prototyping activities at LESIA for E-ELT scale pyramid wavefront sensor (WFS) and real-time computer (RTC), our activities on end-to-end AO simulations and the current preliminary design of SCAO subsystems. We finish by presenting the implementation and current design studies for the high-contrast imaging mode of MICADO, which will make use of the SCAO correction offered to the instrument.

MAORY is one of the four instruments for the E-ELT approved for construction. It is an adaptive optics module offering two compensation modes: multi-conjugate and single-conjugate adaptive optics. The project has recently entered its phase B. A system-level overview of the current status of the project is given in this paper.

The MAORY system is the Multi-Adaptive Optics module for the European Extremely Large Telescope first light. MAORY should provide high and homogeneous image quality over the MICADO Field of View (about 1 arcmin diameter) and still an acceptable correction up to the 3 arcmin technical Field of View. The baseline of MAORY is therefore to rely upon the use of multiple Laser Guide Stars (6), multiple Natural Guide Stars (3) and multiple Deformable Mirrors correction. The Real-Time Computer is a key sub-system of MAORY. It must collect the measurements from various sensing devices and drive thousands of actuators. Many correction loops are foreseen with different update rates. The main requirements concerning the system dimensioning and Real-Rime performance depend on the sensors and on the actuators interface and on the Real-Time Data Processing. In this paper we give a preliminary description of the MAORY Real-Time Control system functional requirements derived from the system baseline at the beginning of the instrument Phase B.

The Multiconjugate Adaptive Optics RelaY (MAORY) is and Adaptive Optics module to be mounted on the ESO European-Extremely Large Telescope (E-ELT). It is a hybrid Natural and Laser Guide System that will perform the correction of the atmospheric turbulence volume above the telescope feeding the Multi-AO Imaging Camera for Deep Observations Near Infrared spectro-imager (MICADO). We developed an end-to-end Monte- Carlo adaptive optics simulation tool to investigate the performance of a the MAORY and the calibration, acquisition, operation strategies. MAORY will implement Multiconjugate Adaptive Optics combining Laser Guide Stars (LGS) and Natural Guide Stars (NGS) measurements. The simulation tool implements the various aspect of the MAORY in an end to end fashion. The code has been developed using IDL and uses libraries in C++ and CUDA for efficiency improvements. Here we recall the code architecture, we describe the modeled instrument components and the control strategies implemented in the code., Comment: 6 pages, 1 figure, Proceeding 9909 310 of the conference SPIE Astronomical Telescopes + Instrumentation 2016, 26 June 1 July 2016 Edinburgh, Scotland, UK

Over the last few years increasing consideration has been given to the study of Laser Guide Stars (LGS) for the measurement of the disturbance introduced by the atmosphere in optical and near-infrared astronomical observations from the ground. A possible method for the generation of a LGS is the excitation of the Sodium layer in the upper atmosphere at approximately 90 km of altitude. Since the Sodium layer is approximately 10 km thick, the artificial reference source looks elongated, especially when observed from the edge of a large aperture. The spot elongation strongly limits the performance of the most common wavefront sensors. The centroiding accuracy in a Shack-Hartmann wavefront sensor, for instance, decreases proportionally to the elongation (in a photon noise dominated regime). To compensate for this effect a straightforward solution is to increase the laser power, i.e. to increase the number of detected photons per subaperture. The scope of the work presented in this paper is twofold: an analysis of the performance of the Weighted Center of Gravity algorithm for centroiding with elongated spots and the determination of the required number of photons to achieve a certain average wavefront error over the telescope aperture., 10 pages, 14 figures

Multi-Conjugate Adaptive Optics systems based on sodium Laser Guide Stars may exploit Natural Guide Stars to solve intrinsic limitations of artificial beacons (tip-tilt indetermination and anisoplanatism) and to mitigate the impact of the sodium layer structure and variability. The sodium layer may also have transverse structures leading to differential effects among Laser Guide Stars. Starting from the analysis of the input perturbations related to the Sodium Layer variability, modeled directly on measured sodium layer profiles, we analyze, through a simplified end-to-end simulation code, the impact of the low/medium orders induced on global performance of the European Extremely Large Telescope Multi-Conjugate Adaptive Optics module MAORY., 7 pages, 5 figures, SPIE conference Proceeding

The novel and freely available ‘Patch’ software package can be used to deconvolve images that have spatially variable point spread functions.

We present a general method, based on controlled static aberrations induced in the reflectors, to boost receiver performances in solar concentrators. Imaging mirrors coupled with dense arrays suffer from severe performance degradation since the solar irradiance distribution is bell-shaped: mismatch losses occur in particular when the cells are series connected. The method consists in computing static deformations of the reflecting surfaces that can produce, for an adopted concentration ratio, a light spot matching the receiver features better than conventional reflectors. The surfaces and the deformations have been analytically described employing the Zernike polynomials formalism. The concept here described can be applied to a variety of optical configurations and collecting areas. As an example, we extensively investigated a dense array photovoltaic concentrator, dimensioned for a nominal power of about 10 kWe. The ‘‘flat’’ distribution of light we obtain can exploit the PV device cells close to their efficiency limit. A significant gain is thus obtained, with no need of secondary optics or complex dish segmentation and of special features in the receiver electrical scheme. In the design, based on seven 2.6 m mirrors, we addressed also non-optical aspects as the receiver and the supporting mechanics. Optical and mechanical tolerances are demonstrated not to exceed accurate, but conventional, industrial standards. 2015 Elsevier Ltd.

LINC-NIRVANA is a Fizeau (imaging) interferometer exploiting the full spatial resolution of a 23 m class telescope in the combined beam of the Large Binocular Telescope supported through Multi-Conjugated Adaptive Optics (MCAO). By means of science cases, we show how LINC-NIRVANA takes advantage of the MCAO, increasing the sky coverage of the instrument and the field of view for the Fringe and Flexure tracker. We introduce the MCAO system of LINC-NIRVANA in detail, which in a first step will be installed with two deformable mirrors per arm and has the provision to be upgraded with a third mirror. The MCAO system implements several novel concepts proposed for extremely large telescopes, such as layer oriented MCAO, optical co-adding of guide stars, or Multiple Field of View sensing. LINC-NIRVANA will demonstrate some of the concepts for the first time on sky. To cite this article: W. Gaessler et. al., C. R. Physique 6 (2005).

We present a method for the restoration of astronomical images obtained with Adaptive Optics (AO) systems. In order to maximize the scientific return from AO data and, in general, from the data of the next generation telescopes, we developed a restoration method based on deconvolution for the de-blurring of images degraded by a spatially variable PSF. The deconvolution method is based on a partition of the image domain in partially overlapping sub-domains where the PSF can be assumed to be space invariant. The software, called Patch, is written in IDL language and is freely distributed to the community. Here we report a general description of the method and of its graphical interface. The potentiality of the Software Patch have been tested on two completely different astrophysical scenarios: a crowded stellar field and an extended galaxy. Despite the very conservative assumptions made on the Point Spread Function (assumed to be strongly variable across the field of view), we obtained good results in terms of image reconstruction both for the stellar (point-like) case and for the extended galaxy.

The Multi-Conjugate Adaptive Optics module for the European Extremely Large Telescope has been designed to achieve uniform compensation of the atmospheric turbulence effects on a wide field of view in the near infrared. The design realized in the Phase A of the project is undergoing major revision in order to define a robust baseline in view of the next phases of the project. An overview of the on-going activities is presented.

MAORY is the adaptive optics module of the E-ELT that will feed the MICADO imaging camera through a gravity invariant exit port. MAORY has been foreseen to implement MCAO correction through three high order deformable mirrors driven by the reference signals of six Laser Guide Stars (LGSs) feeding as many Shack-Hartmann Wavefront Sensors. A three Natural Guide Stars (NGSs) system will provide the low order correction. We develop a code for the end-to-end simulation of the MAORY adaptive optics (AO) system in order to obtain high-delity modeling of the system performance. It is based on the IDL language and makes extensively uses of the GPUs. Here we present the architecture of the simulation tool and its achieved and expected performance., Comment: 8 pages, 4 figures, presented at SPIE Astronomical Telescopes + Instrumentation 2014 in Montr\'eal, Quebec, Canada, with number 9148-251

LINC-NIRVANA (LN) is the near-infrared, Fizeau-type imaging interferometer for the Large Binocular Telescope (LBT) on Mt. Graham, Arizona, USA (3267m of elevation). The instrument is currently being built by a consortium of German and Italian institutes under the leadership of the Max Planck Institute for Astronomy (MPIA) in Heidelberg, Germany. It will combine the radiation from both 8.4m primary mirrors of LBT in such a way that the sensitivity of a 11.9m telescope and the spatial resolution of a 22.8m telescope will be obtained within a 10.5arcsec x 10.5arcsec scientific field of view. Interferometric fringes of the combined beams are tracked in an oval field with diameters of 1 and 1.5arcmin. In addition, both incoming beams are individually corrected by LN’s multi-conjugate adaptive optics (MCAO) system to reduce atmospheric image distortion over a circular field of up to 6arcmin in diameter. This paper gives a comprehensive technical overview of the instrument comprising the detailed design of LN’s four major systems for interferometric imaging and fringe tracking, both in the NIR range of 1 - 2.4μm, as well as atmospheric turbulence correction at two altitudes, both in the visible range of 0.6 - 0.9μm. The resulting performance capabilities and a short outlook of some of the major science goals will be presented. In addition, the roadmap for the related assembly, integration and verification (AIV) process will be discussed. To avoid late interface-related risks, strategies for early hardware as well as software interactions with the telescope have been elaborated. The goal is to ship LN to the LBT in 2014.