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MagAO-X is the extreme coronagraphic adaptive optics (AO) instrument for the 6.5-meter Magellan Clay telescope and is currently undergoing a comprehensive batch of upgrades. One innovation that the instrument features is a deformable mirror…

We investigate the improvements in Shack-Hartmann wavefront sensor image processing that can be realised using total variation minimisation techniques to remove noise from these images. We perform Monte-Carlo simulation to demonstrate that…

Instrumentation and Methods for Astrophysics · Physics 2015-04-14 Alastair Basden

GRAVITY is a second generation instrument for the VLT Interferometer, designed to enhance the near-infrared astrometric and spectro-imaging capabilities of VLTI. Combining beams from four telescopes, GRAVITY will provide an astrometric…

EAGLE is the multi-object, spatially-resolved, near-IR spectrograph instrument concept for the E-ELT, relying on a distributed Adaptive Optics, so-called Multi Object Adaptive Optics. This paper presents the results of a phase A study.…

This paper describes the data preprocessing and reduction methods together with SLODAR analysis and wind profiling techniques for GeMS: the Gemini MCAO System. The wavefront gradient measurements of the five GeMS's Shack-Hartmann sensors,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Angela Cortés , Benoit Neichel , Andrés Guesalaga , James Osborn , Francois Rigaut , Dani Guzman

The exoplanetary science through direct imaging and spectroscopy will largely expand with the forthcoming development of new instruments at the VLT (SPHERE), Gemini (GPI), Subaru (HiCIAO), and Palomar (Project 1640) observatories. All these…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 P. Martinez , E. Aller-Carpentier , M. Kasper , A. Boccaletti , C. Dorrer , J. Baudrand

We propose to explore a cascade extreme Adaptive optics (ExAO) approach with a second stage based on a Zernike wavefront sensor (ZWFS) for exoplanet imaging and spectroscopy. Most exoplanet imagers currently use a single-stage ExAO to…

Instrumentation and Methods for Astrophysics · Physics 2023-09-20 Mamadou N'Diaye , Arthur Vigan , Byron Engler , Markus Kasper , Serban Leveratto , Johan Floriot , Michel Marcos , Christophe Bailet , Kjetil Dohlen

We investigate the focal plane wavefront sensing technique, known as Phase Diversity, at the scientific focal plane of a segmented mirror telescope with an adaptive optics (AO) system. We specifically consider an optical system imaging a…

Instrumentation and Methods for Astrophysics · Physics 2021-05-03 Masen Lamb , Carlos Correia , Suresh Sivanandam , Robin Swanson , Polina Zavyalova

Adaptive optics systems are critical in any application where highly resolved imaging or beam control must be performed through a dynamic medium. Such applications include astronomy and free-space optical communications, where light…

The Global-Multi Conjugated Adaptive Optics (GMCAO) approach offers an alternative way to correct an adequate scientific Field of View (FoV) using only natural guide stars (NGSs) to extremely large ground-based telescopes. Thus, even in the…

Instrumentation and Methods for Astrophysics · Physics 2020-07-01 Elisa Portaluri , Valentina Viotto , Roberto Ragazzoni , Carmelo Arcidiacono , Maria Bergomi , Marco Dima , Davide Greggio , Jacopo Farinato , Demetrio Magrin

Bright single and binary stars were observed at the 4.1-m telescope with a fast electron-multiplication camera in the regime of partial turbulence correction by the visible-light adaptive optics system. We compare the angular resolution…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 A. Tokovinin , R. Cantarutti , R. Tighe , P. Schurter , N. van der Bliek , M. Martinez , E. Mondaca

High throughput, low inner working angle (IWA) phase masks coronagraphs are essential to directly image and characterize (via spectroscopy) earth-like planets. However, the performance of low-IWA coronagraphs is limited by residual pointing…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Garima Singh , Olivier Guyon , Pierre Baudoz , Nemanja Jovanovic , Frantz Martinache , Tomoyuki Kudo , Eugene Serabyn , Jonas G Kuhn

The Santa Cruz Extreme AO Lab (SEAL) is a new visible-wavelength testbed designed to advance the state of the art in wavefront control for high contrast imaging on large, segmented, ground-based telescopes. SEAL provides multiple options…

We present a promising approach to the extremely fast sensing and correction of small wavefront errors in adaptive optics systems. As our algorithm's computational complexity is roughly proportional to the number of actuators, it is…

Instrumentation and Methods for Astrophysics · Physics 2016-11-26 Christoph U. Keller , Visa Korkiakoski , Niek Doelman , Rufus Fraanje , Raluca Andrei , Michel Verhaegen

A multi-object spectrograph on the forthcoming European Extremely Large Telescope will be required to operate with good sky coverage. Many of the interesting deep cosmological fields were deliberately chosen to be free of bright foreground…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 Alastair Basden , Chris Evans , Tim Morris

For ExAO instruments for the Giant Segmented Mirror Telescopes (GSMTs), alternative architectures of WFS are under consideration because there is a tradeoff between detector size, speed, and noise that reduces the performance of GSMT-ExAO…

Several Wide Field of view Adaptive Optics (WFAO) concepts like Multi-Conjugate AO (MCAO), Multi-Object AO (MOAO) or Ground-Layer AO (GLAO) are currently studied for the next generation of Extremely Large Telescopes (ELTs). All these…

Astrophysics · Physics 2009-11-13 B. Neichel , T. Fusco , J. -M. Conan

The ability to characterize exoplanets by spectroscopy of their atmospheres requires direct imaging techniques to isolate planet signal from the bright stellar glare. One of the limitations with the direct detection of exoplanets, either…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 Garima Singh , Julien Lozi , Olivier Guyon , Pierre Baudoz , Nemanja Jovanovic , Frantz Martinache , Tomoyuki Kudo , Eugene Serabyn , Jonas Kuhn

The optimization and scheduling of scientific observations done with instrumentation supported by adaptive optics could greatly benefit from the forecast of PSF figures of merit (FWHM, Strehl Ratio, Encircle Energy and contrast), that…

Instrumentation and Methods for Astrophysics · Physics 2020-12-15 A. Turchi , G. Agapito , E. Masciadri , O. Beltramo-Martin , E. Pinna , J. F. Sauvage , T. Fusco , B. Neichel , J. Milli

The direct imaging of potentially habitable Exoplanets is one prime science case for the next generation of high contrast imaging instruments on ground-based extremely large telescopes. To reach this demanding science goal, the instruments…