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Related papers: Angular Differential Imaging: a Powerful High-Cont…

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An adaptive optics (AO) system based on stochastic parallel gradient descent (SPGD) algorithm is proposed to reduce the speckle noises in the optical system of stellar coronagraph in order to further improve the contrast. The principle of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Bing Dong , Deqing Ren , Xi Zhang

Context. The direct detection of exoplanets with high-contrast imaging requires advanced data processing methods to disentangle potential planetary signals from bright quasi-static speckles. Among them, angular differential imaging (ADI)…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 F. Cantalloube , D. Mouillet , L. M. Mugnier , J. Milli , O. Absil , C. A. Gomez Gonzalez , G. Chauvin , J. -L Beuzit , A. Cornia

Optical stellar interferometers have demonstrated milli-arcsecond resolution with few apertures spaced hundreds of meters apart. To obtain rich direct images, many apertures will be needed, for a better sampling of the incoming wavefront.…

Instrumentation and Methods for Astrophysics · Physics 2014-09-17 Arun Surya , Swapan K. Saha , Antoine Labeyrie

Most of the high-contrast imaging (HCI) data-processing techniques used over the last 15 years have relied on the angular differential imaging (ADI) observing strategy, along with subtraction of a reference point spread function (PSF) to…

Instrumentation and Methods for Astrophysics · Physics 2021-12-08 Carl-Henrik Dahlqvist , Faustine Cantalloube , Olivier Absil

Hyperspectral images are high-dimensional datasets comprising hundreds of contiguous spectral bands, enabling detailed analysis of materials and surfaces. Hyperspectral anomaly detection (HAD) refers to the technique of identifying and…

Computer Vision and Pattern Recognition · Computer Science 2025-07-14 Aayushma Pant , Arbind Agrahari Baniya , Tsz-Kwan Lee , Sunil Aryal

We describe a new instrument that forms the core of a long-term high contrast imaging program at the 200-inch Hale Telescope at Palomar Observatory. The primary scientific thrust is to obtain images and low-resolution spectroscopy of brown…

Direct exoplanet detection is limited by speckle noise in the point spread function (PSF) of the central star. This noise can be reduced by subtracting PSF images obtained simultaneously in adjacent narrow spectral bands using a…

We present a method for speckle holography that is optimised for crowded fields. Its two key features are an iterativ improvement of the instantaneous Point Spread Functions (PSFs) extracted from each speckle frame and the (optional)…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 R. Schoedel , S. Yelda , A. Ghez , J. H. V. Girard , L. Labadie , R. Rebolo , A. Perez-Garrido , M. R. Morris

High-contrast imaging presents us with the opportunity to study circumstellar disks and the planets still embedded within them -- providing key insights into the formation and evolution of planetary systems. However, the post-processing…

Earth and Planetary Astrophysics · Physics 2022-08-31 Kellen Lawson , Thayne Currie , John Wisniewski , Tyler Groff , Michael McElwain , Joshua Schlieder

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

Aims: In this work, we discuss a way to combine High Dispersion Spectroscopy and High Contrast Imaging (HDS+HCI). For a planet located at a resolvable angular distance from its host star, the starlight can be reduced up to several orders of…

Spectral and grating-based differential phase-contrast X-ray imaging are two emerging technologies that offer additional information compared with conventional attenuation-based X-ray imaging. In the case of spectral imaging,…

Medical Physics · Physics 2020-01-31 Korbinian Mechlem , Thorsten Sellerer , Manuel Viermetz , Julia Herzen , Franz Pfeiffer

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

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…

The speed and quality of single-pixel imaging (SPI) are fundamentally limited by image modulation frequency and by the levels of optical noise and compression noise. In an approach to come close to these limits, we introduce a SPI…

Optics · Physics 2022-05-25 Anna Pastuszczak , Rafał Stojek , Piotr Wróbel , Rafał Kotyński

Deconvolution of the telescope Point Spread Function (PSF) is necessary for even moderate dynamic range imaging with interferometric telescopes. The process of deconvolution can be treated as a search for a model image such that the…

Astrophysics · Physics 2009-11-10 S. Bhatnagar , T. J. Cornwell

Speckle Noise is the dominant source of error in high contrast imaging with adaptive optics system. We discuss the potential for wavefront sensing telemetry to calibrate speckle noise with sufficient precision and accuracy so that it can be…

ADI and SDI are well-established high-contrast imaging techniques, but their application is challenging for companions at small angular separations. The aim of this paper is to investigate to what extent adaptive-optics assisted,…

Earth and Planetary Astrophysics · Physics 2018-10-03 H. J. Hoeijmakers , H. Schwarz , I. A. G. Snellen , R. J. de Kok , M. Bonnefoy , G. Chauvin , A. M. Lagrange , J. H. Girard

Change detection is a widely adopted technique in remote sense imagery (RSI) analysis in the discovery of long-term geomorphic evolution. To highlight the areas of semantic changes, previous effort mostly pays attention to learning…

Computer Vision and Pattern Recognition · Computer Science 2023-05-31 Supeng Wang , Yuxi Li , Ming Xie , Mingmin Chi , Yabiao Wang , Chengjie Wang , Wenbing Zhu

The Planetary Systems Imager (PSI) is a proposed instrument for the Thirty Meter Telescope (TMT) that provides an extreme adaptive optics (AO) correction to a multi-wavelength instrument suite optimized for high contrast science. PSI's…