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The Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) contains the only currently operating coronagraph in space that is not trained on the Sun. In an era of extreme--adaptive-optics--fed coronagraphs, and with the…

Instrumentation and Methods for Astrophysics · Physics 2019-05-17 J. H. Debes , B. Ren , G. Schneider

For direct imaging of exoplanets, a stellar coronagraph helps to remove the image of an observed bright star by attenuating the diffraction effects caused by the telescope aperture of diameter D. The Dual Zone Phase Mask (DZPM) coronagraph…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 M. N'Diaye , K. Dohlen , S. Cuevas , R. Soummer , C. Sánchez-Pérez , F. Zamkotsian

We present the results of the first laboratory experiment of checkerboard shaped pupil binary mask coronagraphs using visible light, in the context of the R&D activities for future mid-infrared space missions such as the 3.5 m SPICA…

Astrophysics · Physics 2009-11-11 K. Enya , S. Tanaka , L. Abe , T. Nakagawa

The behavior of an adaptive optics (AO) system for ground-based high contrast imaging (HCI) dictates the achievable contrast of the instrument. In conditions where the coherence time of the atmosphere is short compared to the speed of the…

Instrumentation and Methods for Astrophysics · Physics 2021-08-23 Maaike A. M. van Kooten , Rebecca Jensen-Clem , Sylvain Cetre , Sam Ragland , Charlotte Z. Bond , J. Fowler , Peter Wizinowich

In a previous paper, we discussed an original solution to improve the performances of coronagraphs by adding, in the optical scheme, an adaptive hologram removing most of the residual speckle starlight. In our simulations, the detection…

Instrumentation and Methods for Astrophysics · Physics 2011-02-17 Davide Ricci , Hervé Le Coroller , Antoine Labeyrie , Pierre Piron

Direct imaging of exo-Earths and search for life is one of the most exciting and challenging objectives for future space observatories. Segmented apertures in space will be required to reach the needed large diameters beyond the…

Project 1640 is a high-contrast imaging instrument recently commissioned at Palomar observatory. A combination of a coronagraph with an integral field spectrograph (IFS), Project 1640 is designed to detect and characterize extrasolar…

Holographic displays are a promising technology for immersive visual experiences, and their potential for compact form factor makes them a strong candidate for head-mounted displays. However, at the short propagation distances needed for a…

One of the key science goals for extremely large telescopes (ELTs) is the detailed characterization of already known directly imaged exoplanets. The typical adaptive optics (AO) Nyquist control region for ELTs is ~0.4 arcseconds, placing…

Instrumentation and Methods for Astrophysics · Physics 2016-11-23 Benjamin L. Gerard , Christian Marois

As the performance of coronagraphs improves, the achievable contrast is more and more dependent of the shape of the pupil. The future generation of space and ground based coronagraphic instruments will have to achieve high contrast levels…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 Johan Mazoyer , Laurent Pueyo , Colin Norman , Mamadou N'Diaye , Dimitri Mawet , Rémi Soummer , Marshall Perrin , Élodie Choquet , Alexis Carlotti

High-contrast imaging observations of large angular diameter stars enable complementary science questions to be addressed compared to the baseline goals of proposed missions like the Terrestrial Planet Finder-Coronagraph, New World's…

Earth and Planetary Astrophysics · Physics 2015-05-14 Justin R. Crepp , Suvrath Mahadevan , Jian Ge

Context. Several exoplanet direct imaging instruments will soon be in operation. They use an extreme adaptive optics (XAO) system to correct the atmospheric turbulence and provide a highly-corrected beam to a near-infrared (NIR) coronagraph…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 M. N'Diaye , K. Dohlen , T. Fusco , B. Paul

In Europe the 20% of the CT scans cover the thoracic region. The acquired images contain information about the cardiovascular system that often remains latent due to the lack of contrast in the cardiac area. On the other hand, the contrast…

Computer Vision and Pattern Recognition · Computer Science 2018-07-06 Gianmarco Santini , Lorena M. Zumbo , Nicola Martini , Gabriele Valvano , Andrea Leo , Andrea Ripoli , Francesco Avogliero , Dante Chiappino , Daniele Della Latta

High contrast imaging using coronagraphy is one of the main avenues to enable the search for life on extrasolar Earth analogs. The HiCAT testbed aims to demonstrate coronagraphy and wavefront control for segmented on-axis space telescopes…

Instrumentation and Methods for Astrophysics · Physics 2019-03-11 Christopher Moriarty , Keira Brooks , Remi Soummer , Marshall Perrin , Thomas Comeau , Gregory Brady , Rob Gontrum , Peter Petrone

Direct imaging of exoplanets is crucial for advancing our understanding of planetary systems beyond our solar system, but it faces significant challenges due to the high contrast between host stars and their planets. Wavefront aberrations…

Earth and Planetary Astrophysics · Physics 2025-01-06 Brandon Y. Feng , Rodrigo Ferrer-Chávez , Aviad Levis , Jason J. Wang , Katherine L. Bouman , William T. Freeman

Digital imaging sensor technology has continued to outpace development in optical technology in modern imaging systems. The resulting quality loss attributable to lateral chromatic aberration is becoming increasingly significant as sensor…

Computer Vision and Pattern Recognition · Computer Science 2021-10-11 Daniel J. Blueman

Context: High contrast imaging is a powerful technique to detect and characterize planetary companions at large orbital separations from their parent stars. Aims: We aim at studying the limiting magnitude of the VLT/SPHERE Adaptive Optics…

Instrumentation and Methods for Astrophysics · Physics 2022-11-30 M. I. Jones , J. Milli , I. Blanchard , Z. Wahhaj , R. de Rosa , C. Romero

High precision differential astrometry assesses the positions, distances, and motions of celestial objects in relation to the stars. The focal plane of such space telescope must be calibrated with a precision down to the level of 1e-5 pixel…

Instrumentation and Methods for Astrophysics · Physics 2024-10-30 Fabrice Pancher , Sebastien Soler , Fabien Malbet , Manon Lizzana , Pierre Kern , Thierry Lepine , Alain Leger

Characterization of directly imaged exoplanets is one of the most eagerly anticipated science functions of the James Webb Space Telescope. MIRI, the mid-IR instrument has the capability to provide unique spatially resolved photometric data…

We present here new experimental results on high contrast imaging of 10^{-7} at 4.5Lambda/D (Lambda = 0.820 microns) by combining a circular focal plane mask (coronagraph) of 2.5Lambda/D diameter and a multi-Gaussian pupil plane mask. Both…

Astrophysics · Physics 2009-11-10 Abhijit Chakraborty , Laird A. Thompson , Mike Rogosky
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