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Accurate measurement of polarization in spectral lines is important for the reliable inference of magnetic fields on the Sun. For ground based observations, polarimetric precision is severely limited by the presence of Earth's atmosphere.…

Instrumentation and Detectors · Physics 2012-11-05 K. Nagaraju , Alex Feller

Astronomical telescopes suffer from a tradeoff between field of view (FoV) and image resolution: increasing the FoV leads to an optical field that is under-sampled by the science camera. This work presents a novel computational imaging…

Instrumentation and Methods for Astrophysics · Physics 2025-08-07 Robin Swanson , Esther Y. H. Lin , Masen Lamb , Suresh Sivanandam , Kiriakos N. Kutulakos

Optical beams and starlight distorted by atmospheric turbulence can be corrected with adaptive optics systems to enable efficient coupling into single-mode fibers. Deformable mirrors, used to flatten the wavefront in astronomical…

Silicon-based micro-electromechanical systems (MEMS) can be fabricated using bulk and surface micromachining technology. A micro mirror designed as an oscillatory MEMS constitutes a prominent example. Typically, in order to minimize energy…

Mesoscale and Nanoscale Physics · Physics 2018-06-14 Ulrike Nabholz , Wolfgang Heinzelmann , Jan E. Mehner , Peter Degenfeld-Schonburg

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

We use data from the Transiting Exoplanet Survey Satellite (TESS) to search for, and set limits on, optical to near-infrared photometric variability of the well-vetted, candidate James Webb Space Telescope (JWST) spectrophotometric…

The current direct observations of brown dwarfs and exoplanets have been obtained using instruments not specifically designed for overcoming the large contrast ratio between the host star and any wide-separation faint companions. However,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 Sasha Hinkley

This paper is a response to a call for white papers solicited by Gemini Observatory and its Science and Technology Advisory Committee, to help define the science case and requirements for a new Gemini instrument, envisaged to consist of a…

Wide Field Adaptive Optics (WFAO) systems are among the most sophisticated AO systems available today on large telescopes. The knowledge of the vertical spatio-temporal distribution of the wind speed (WS) and direction (WD) are fundamental…

Instrumentation and Methods for Astrophysics · Physics 2018-01-25 G. Sivo , A. Turchi , E. Masciadri , A. Guesalga , B. Neichel

Future high-contrast imagers on ground-based extremely large telescopes will have to deal with the segmentation of the primary mirrors. Residual phase errors coming from the phase steps at the edges of the segments will have to be minimized…

Instrumentation and Methods for Astrophysics · Physics 2020-12-08 A. Vigan , M. Postnikova , A. Caillat , J. -F. Sauvage , K. Dohlen , K. El Hadi , T. Fusco , M. Lamb , M. N'Diaye

Atmospheric optical turbulence seriously limits the performance of high angular resolution instruments. An 8-night campaign of measurements was carried out at the LAMOST site in 2011, to characterize the optical turbulence. Two instruments…

Instrumentation and Methods for Astrophysics · Physics 2015-05-21 L. -Y. Liu , C. Giordano , Y. -Q. Yao , J. Vernin , M. Chadid , H. -S. Wang , J. Yin , Y. -P. Wang

For extremely large telescopes, adaptive optics will be required to correct the Earth's turbulent atmosphere. The performance of tomographic adaptive optics is strongly dependent on the vertical distribution (profile) of this turbulence. An…

Instrumentation and Methods for Astrophysics · Physics 2019-06-26 O. J. D. Farley , J. Osborn , T. Morris , T. Fusco , B. Neichel , C. Correia , R. W. Wilson

We present a new method to probe atmospheric pressure on Earthlike planets using (O2-O2) dimers in the near-infrared. We also show that dimer features could be the most readily detectable biosignatures for Earthlike atmospheres, and may…

Earth and Planetary Astrophysics · Physics 2014-05-21 Amit Misra , Victoria Meadows , Mark Claire , Dave Crisp

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

The Mid-infrared ELT Imager and Spectrograph (METIS) is a first-generation instrument for the Extremely Large Telescope (ELT), Europe's next-generation 39 m ground-based telescope for optical and infrared wavelengths. METIS will offer…

Sensors and actuators based on resonant micro-electro-mechanical systems (MEMS), such as scanning micro mirrors, are well-established in automotive and consumer products. As the areas of application broaden, the requirements for the MEMS…

Applied Physics · Physics 2020-02-07 Ulrike Nabholz , Florian Stockmar , Jan E. Mehner , Peter Degenfeld-Schonburg

Future large space- or ground-based telescopes will offer the resolution and sensitivity to probe the habitable zone of a large sample of nearby stars for exo-Earth imaging. To this end, such facilities are expected to be equipped with a…

Instrumentation and Methods for Astrophysics · Physics 2020-10-12 M. Beaulieu , P. Martinez , L. Abe , C. Gouvret , P. Baudoz , R. Galicher

Real-time seeing and outer scale estimation at the location of the focus of a telescope is fundamental for the adaptive optics systems dimensioning and performance prediction, as well as for the operational aspects of instruments. This…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Patrice Martinez

Stellar coronagraphs rely on deformable mirrors (DMs) to correct wavefront errors and create high contrast images. Imperfect control of the DM limits the achievable contrast and, therefore, the DM control electronics must provide fine…

This paper presents a study of the atmospheric refraction and its effect on the light coupling efficiency in an instrument using single-mode optical fibers. We show the analytical approach which allowed us to assess the need to correct the…

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