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Related papers: Speckle Statistics in Adaptively Corrected Images

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Line intensity mapping (LIM) is an emerging observational method to study the large-scale structure of the Universe and its evolution. LIM does not resolve individual sources but probes the fluctuations of integrated line emissions. A…

Astrophysics of Galaxies · Physics 2020-06-03 Kana Moriwaki , Nina Filippova , Masato Shirasaki , Naoki Yoshida

Imaging through dynamic scattering media, such as biological tissue, presents a fundamental challenge due to light scattering and the formation of speckle patterns. These patterns not only degrade image quality but also decorrelate rapidly,…

Radiative transfer coupled with highly realistic simulations of the solar atmosphere is routinely used to infer the physical properties underlying solar observations. Due to its computational efficiency, the method of short-characteristics…

Solar and Stellar Astrophysics · Physics 2018-04-17 Courtney L. Peck , Serena Criscuoli , Mark P. Rast

Change detection plays an important role in most video-based applications. The first stage is to build appropriate background model, which is now becoming increasingly complex as more sophisticated statistical approaches are introduced to…

Computer Vision and Pattern Recognition · Computer Science 2014-05-27 Dong Liang , Shun'ichi Kaneko

Spectroscopy in the infrared provides a means to assess important properties of the plasma in gaseous nebulae. We present some of our own work that illustrates the need for interactions between the themes of this conference - astronomical…

Cosmic shear measurements rely on our ability to measure and correct the Point Spread Function (PSF) of the observations. This PSF is measured using stars in the field, which give a noisy measure at random points in the field. Using Wiener…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. Amara , A. Refregier , S. Paulin-Henriksson

A long-held vision has been to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, and reveal interacting gas flows in binary systems. An…

Instrumentation and Methods for Astrophysics · Physics 2015-08-12 Dainis Dravins , Tiphaine Lagadec , Paul D. Nuñez

High-contrast long-slit spectrographs can be used to characterize exoplanets. High-contrast long-slit spectroscopic data are however corrupted by stellar leakages which largely dominate other signals and make the process of extracting the…

Instrumentation and Methods for Astrophysics · Physics 2023-10-11 Samuel Thé , Éric Thiébaut , Loïc Denis , Thibault Wanner , Rémi Thiébaut , Maud Langlois , Ferréol Soulez

A new method which enables us to estimate the inclination of Class I young stellar objects is proposed. Since Class I objects are not spherically symmetric, it is likely that the observed feature is sensitive to the inclination of the…

Astrophysics · Physics 2009-11-07 T. Nakazato , T. Nakamoto , M. Umemura

A new theoretical technique for understanding, analyzing and developing optical systems is presented. The approach is statistical in nature, where information about an object under investigation is discovered, by examining deviations from a…

Optics · Physics 2016-09-20 Damien P. Kelly

Adaptive optics (AO) systems and image reconstruction algorithms are indispensable tools when it comes to high-precision astrometry. In this paper, we analyze the potential of combining both techniques, i.e. by applying image reconstruction…

Instrumentation and Methods for Astrophysics · Physics 2019-03-13 Felix Bosco , Jörg-Uwe Pott , Rainer Schödel

CONTEXT. Many massive stars have nearby companions whose presence hamper their characterization through spectroscopy. AIMS. We want to continue obtaining spatially resolved spectroscopy of close massive visual binaries to derive their…

Solar and Stellar Astrophysics · Physics 2021-02-03 J. Maíz Apellániz , R. H. Barbá , C. Fariña , A. Sota , M. Pantaleoni González , G. Holgado , I. Negueruela , S. Simón-Díaz

Speckle patterns are formed by random interferences of mutually coherent beams. While speckles are often considered as an unwanted noise in many areas, they also formed the foundation for the development of numerous speckle-based imaging,…

Optics · Physics 2022-07-26 Vijayakumar Anand

We derive general equations for non-linearity corrections and statistical uncertainty (variance) estimates for data acquired with near-infrared detectors employing correlated double sampling, multiple correlated double sampling (Fowler…

Astrophysics · Physics 2009-11-10 W. D. Vacca , M. C. Cushing , J. T. Rayner

Speckle-based phase-contrast X-ray imaging (SB-PCXI) can reconstruct high-resolution images of weakly-attenuating materials that would otherwise be indistinguishable in conventional attenuation-based imaging. The experimental setup of…

Medical Physics · Physics 2023-07-31 Samantha J. Alloo , Kaye S. Morgan , David M. Paganin , Konstantin M. Pavlov

Joint photocount distributions of a weak twin beam acquired by an iCCD camera are analyzed with respect to the beam spatial correlations. A method for extracting these correlations from the experimental joint photocount distributions is…

Quantum Physics · Physics 2018-12-11 Jan Perina , Vaclav Michalek , Ondrej Haderka

Light echoes give us a unique perspective on the nature of supernovae and non-terminal stellar explosions. Spectroscopy of light echoes can reveal details on the kinematics of the ejecta, probe asymmetry, and reveal details on its…

One of the main goals of modern observational cosmology is to map the large scale structure of the Universe. A potentially powerful approach for doing this would be to exploit three-dimensional spectral maps, i.e. the specific intensity of…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-18 Roland de Putter , Gilbert P. Holder , Tzu-Ching Chang , Olivier Dore

We have developed a new technique for weak lensing analysis, with which the effect of the point spread function (PSF) on small galaxy images can be corrected for accurately. Rather than relying on weighted second moments of detected images,…

Astrophysics · Physics 2016-08-30 Konrad Kuijken

We have developed photometric techniques that can be applied to images with highly-variable backgrounds, as well as to slightly-extended objects (object size comparable to or smaller than PSF size). We have shown that ordinary stellar…

Astrophysics · Physics 2009-11-07 Andrew E. Dolphin , Robert C. Kennicutt