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A new coronagraphic instrument for the Large Binocular Telescope (LBT) has successfully passed the conceptual design phase. SHARK-NIR channel will be installed in one arm of the Large Binocular Telescope and it is designed to use different coronagraphic techniques, both to match as much as possible the different requirements of the different science cases and to explore the capabilities of such techniques for the next-generation of ELTs. By exploiting the combination with SHARK-VIS channel mounted at the other LBT arm, the instrument will offer simultaneous coronagraphic observations at different wavelengths, characterized by high contrast, even for relatively faint targets. This will be achievable thanks to the very efficient Adaptive Optics (AO) systems already operating at LBT (First Light AO, FLAO). Furthermore, the latter will be soon upgraded with new detectors, promising even better performance in terms of limiting magnitude. In this paper we present the status of the SHARK-NIR channel design.

Enabling accurate morphological and photometric analysis across a wide Field of View (FoV) is one of the keyscience requirement for multi-conjugate adaptive optics systems. With this motivation we present a study aimedat the investigation of the performance of Global-MCAO (GMCAO). Such an innovative concept, based onnatural guide stars in a wide technical FoV, addresses the need for an increase of the sky coverage, which is akey ingredient for future MCAO-based VLT instruments and for the forthcoming E-ELT. Using a tomographicsimulation tool, we compute a map of the Strehl Ratio in a 250′′ × 250′′ area, matching the Chandra Deep FieldSouth survey. Mock images of star and galactic fields are then built using such a map and analyzed as if theywere real and observed with the E-ELT instrumentation. We perform the source detection and two-dimensionallight-profile modeling using the IRAF/ELLIPSE code and we then compare the recovered parameters with theintrinsic data. The good match of our results claims that GMCAO is a reliable approach that can rebuild theAO concepts and can provide a frame of reference for a number of science cases.

In this paper, we discuss the feasibility and the performance assessment of a possible MCAO system for E-ELT, basedon the novel concept of Global MCAO, which takes advantage of a very wide technical FoV to perform adaptive opticscorrection using only natural guide stars, with the aim to increase the sky coverage. The technique envisages thedefinition of Virtual-DMs, as tools for the global reconstruction. This investigation has been carried out during afeasibility study we performed for ESO, in which we combined computations, simulations and literature. The aim of thisanalysis is to identify and review the main parameters and the technical issues, which would act as error sources in a realGMCAO system, evaluating their contribution to the overall performance. The study involves both issues related to thePyramid WFS in general, and to the GMCAO case in particular, including the wavelength and FoV size selection, thenumber of guide stars and reconstructed Virtual-DMs, and actual components parameters.

This article presents a proposal aimed at investigating the technical feasibility and the scientific capabilities of high contrast cameras to be implemented at LBT. Such an instrument will fully exploit the unique LBT capabilities in Adaptive Optics (AO) as demonstrated by the First Light Adaptive Optics (FLAO) system, which is obtaining excellent results in terms of performance and reliability. The aim of this proposal is to show the scientific interest of such a project, together with a conceptual opto-mechanical study which shows its technical feasibility, taking advantage of the already existing AO systems, which are delivering the highest Strehl experienced in nowadays existing telescopes. Two channels are foreseen for SHARK, a near infrared channel (2.5-0.9 um) and a visible one (0.9 – 0.6 um), both providing imaging and coronagraphic modes. The visible channel is equipped with a very fast and low noise detector running at 1.0 kfps and an IFU spectroscopic port to provide low and medium resolution spectra of 1.5 x 1.5 arcsec fields. The search of extra solar giant planets is the main science case and the driver for the technical choices of SHARK, but leaving room for several other interesting scientific topics, which will be briefly depicted here.