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Related papers: SFADI: the Speckle-Free Angular Differential Imagi…

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Coded aperture snapshot spectral imaging (CASSI) is a technique used to reconstruct three-dimensional hyperspectral images (HSIs) from one or several two-dimensional projection measurements. However, fewer projection measurements or more…

Image and Video Processing · Electrical Eng. & Systems 2024-10-28 Qile Zhao , Xianhong Zhao , Xu Ma , Xudong Chen , Gonzalo R. Arce

Direct imaging of exoplanets requires very high contrast levels, which are obtained using coronagraphs. But residual quasi-static aberrations create speckles in the focal plane downstream of the coronagraph which mask the planet. This…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 J. Mazoyer , P. Baudoz , R. Galicher , M. Mas , G. Rousset

Direct imaging of circumstellar disks requires high-contrast and high-resolution techniques. The angular differential imaging (ADI) technique is one of them, initially developed for point-like sources but now increasingly applied to…

Earth and Planetary Astrophysics · Physics 2015-06-05 J. Milli , D. Mouillet , A. M. Lagrange , A. Boccaletti , D. Mawet , G. Chauvin , M. Bonnefoy

The direct detection of exoplanets has been the subject of intensive research in the recent years. Data obtained with future high-contrast imaging instruments optimized for giant planets direct detection are strongly limited by the speckle…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Arthur Vigan , Claire Moutou , Maud Langlois , France Allard , Anthony Boccaletti , Marcel Carbillet , David Mouillet , Isabelle Smith

So far, most of the about 5700 exoplanets have been discovered mainly with radial velocity and transit methods. These techniques are sensitive to planets in close orbits, not being able to probe large star--planet separations. $\mu$-lensing…

Instrumentation and Methods for Astrophysics · Physics 2025-01-15 Riccardo Claudi , Dino Mesa

Although many exoplanets have been indirectly detected over the last years, direct imaging of them with ground-based telescopes remains challenging. In the presence of atmospheric fluctuations, it is ambitious to resolve the high brightness…

Instrumentation and Methods for Astrophysics · Physics 2023-02-08 Jakob Roth , Gianluca Li Causi , Vincenzo Testa , Philipp Arras , Torsten A. Enßlin

Direct imaging of exoplanets requires establishing and maintaining a high contrast dark field (DF) within the science image to a high degree of precision (10^-10). Current approaches aimed at establishing the DF, such as electric field…

Instrumentation and Methods for Astrophysics · Physics 2017-09-26 Kelsey Miller , Olivier Guyon , Jared R Males

Context. Since 1995 and the first discovery of an exoplanet orbiting a main-sequence star, 4000 exoplanets have been discovered using several techniques. However, only a few of these exoplanets were detected through direct imaging. Indeed,…

Instrumentation and Methods for Astrophysics · Physics 2020-07-01 Axel Potier , Raphaël Galicher , Pierre Baudoz , Elsa Huby , Julien Milli , Zahed Wahhaj , Anthony Boccaletti , Arthur Vigan , Mamadou N'Diaye , Jean-François Sauvage

CONTEXT: Combining high-contrast imaging with high-resolution spectroscopy offers a powerful way to detect and characterize exoplanets around nearby stars, despite challenges linked to their faintness. Instruments like VLT/SPHERE are state…

Instrumentation and Methods for Astrophysics · Physics 2025-04-10 S. Martos , A. Bidot , A. Carlotti , D. Mouillet

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…

We present a new method to achieve high-contrast images using segmented and/or on-axis telescopes. Our approach relies on using two sequential Deformable Mirrors to compensate for the large amplitude excursions in the telescope aperture due…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Laurent Pueyo , Colin Norman

The next generation of ground-based instruments aims to break through the knowledge we have on exoplanets by imaging circumstellar environments always closer to the stars. However, direct imaging requires an AO system and high-contrast…

Instrumentation and Methods for Astrophysics · Physics 2019-10-22 A. Potier , P. Baudoz , R. Galicher , E. Huby , G. Singh

We present observations with the planet finder SPHERE of a selected sample of the most promising radial velocity (RV) companions for high-contrast imaging. Using a Monte Carlo simulation to explore all the possible inclinations of the orbit…

High-contrast imaging for the detection and characterization of exoplanets relies on the instrument's capability to block out the light of the host star. Some current post-processing methods for calibrating out the residual speckles use…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Marie Ygouf , Laurent M. Mugnier , David Mouillet , Thierry Fusco , Jean-Luc Beuzit

We present an extension of the spectral deconvolution method (Sparks & Ford 2002) to achieve very high contrast at small inner working radii. We apply the method to the specific case of ground based adaptive optics fed integral field…

Angular and spectral differential imaging is an observational technique of choice to investigate the immediate vicinity of stars. The relative angular motion and spectral scaling between on-axis and off-axis sources are exploited by…

Instrumentation and Methods for Astrophysics · Physics 2024-10-04 Olivier Flasseur , Loïc Denis , Éric Thiébaut , Maud Langlois

The second derivative image (SDI) method is widely applied to sharpen dispersive data features in multi-dimensional spectroscopies such as angle resolved photoemission spectroscopy (ARPES). Here, the SDI function is represented in Fourier…

Detecting small moving targets accurately in infrared (IR) image sequences is a significant challenge. To address this problem, we propose a novel method called spatial-temporal local feature difference (STLFD) with adaptive background…

Computer Vision and Pattern Recognition · Computer Science 2023-09-06 Yongkang Zhao , Chuang Zhu , Yuan Li , Shuaishuai Wang , Zihan Lan , Yuanyuan Qiao

Direct imaging of extra-solar planets is now a reality, especially with the deployment and commissioning of the first generation of specialized ground-based instruments such as the Gemini Planet Imager and SPHERE. These systems will allow…

Instrumentation and Methods for Astrophysics · Physics 2016-01-20 Sandrine J. Thomas , Ruslan Belikov , Eduardo Bendek

Context. Direct imaging of exoplanets takes advantage of state-of-the-art adaptive optics (AO) systems, coronagraphy, and post-processing techniques. Coronagraphs attenuate starlight to mitigate the unfavorable flux ratio between an…

Instrumentation and Methods for Astrophysics · Physics 2022-09-21 Axel Potier , Johan Mazoyer , Zahed Wahhaj , Pierre Baudoz , Gael Chauvin , Raphael Galicher , Garreth Ruane