English
Related papers

Related papers: Stray-light contamination and spatial deconvolutio…

200 papers

Radio telescopes with off-axis feeds, such as the (E)VLA, suffer from "beam squint" in which the two orthogonal circular polarizations sampled have different pointing centers on the sky. Its effects are weak near the beam center but become…

Astrophysics · Physics 2008-07-02 Juan M. Uson , W. D. Cotton

High-contrast scattered light observations have revealed the surface morphology of several dozens of protoplanetary disks at optical and near-infrared wavelengths. Inclined disks offer the opportunity to measure part of the phase function…

Earth and Planetary Astrophysics · Physics 2016-12-07 T. Stolker , C. Dominik , M. Min , A. Garufi , G. D. Mulders , H. Avenhaus

We describe a rapid and direct method for regularizing, post-facto, the point-spread function (PSF) of a telescope or other imaging instrument, across its entire field of view. Imaging instruments in general blur point sources of light by…

Instrumentation and Methods for Astrophysics · Physics 2023-03-20 J. M. Hughes , C. E. DeForest , D. B. Seaton

In this paper we propose a blind deconvolution method which applies to data perturbed by Poisson noise. The objective function is a generalized Kullback-Leibler divergence, depending on both the unknown object and unknown point spread…

Instrumentation and Methods for Astrophysics · Physics 2013-11-25 M. Prato , A. La Camera , S. Bonettini , M. Bertero

We consider the best today available observations of the Sun free of turbulent Earth atmospheric effects, taken with the Solar Optical Telescope (SOT) onboard the Hinode spacecraft. Both the instrumental smearing and the observed stray…

Solar and Stellar Astrophysics · Physics 2015-06-30 Hadis Goodarzi , Serge Koutchmy , Ali Adjabshirizadeh

This paper addresses the problem of high-resolution Doppler blood flow estimation from an ultrafast sequence of ultrasound images. Formulating the separation of clutter and blood components as an inverse problem has been shown in the…

Image and Video Processing · Electrical Eng. & Systems 2020-07-13 Duong-Hung Pham , Adrian Basarab , Ilyess Zemmoura , Jean-Pierre Remenieras , Denis Kouame

The ultimate goal of the "Pi of the Sky" apparatus is observation of optical flashes of astronomical origin and other light sources variable on short timescales. We search mainly for optical emission of Gamma Ray Bursts, but also for…

Instrumentation and Methods for Astrophysics · Physics 2011-11-02 Lech Wiktor Piotrowski

Light-matter interaction in solvents has attracted continuous attention for theoretical prediction and experimental measure, due in part to the simple curiosity to nature, and in part to increasing calls from solvent-involved applications.…

Chemical Physics · Physics 2020-09-01 Jiangbo , Zhao , Cong Qi , Guangrui Li , Markus A. Schmidt

Ptychography involves a sample being illuminated by a coherent, localised probe of illumination. When the probe interacts with the sample, the light is diffracted and a diffraction pattern is detected. Then the probe or sample is shifted…

Numerical Analysis · Mathematics 2023-05-09 Mark Philip Roach

Spectroastrometry is a technique which has the potential to resolve flux distributions on scales of milliarcseconds. In this study, we examine the application of spectroastrometry to binary point sources which are spatially unresolved due…

Astrophysics · Physics 2009-11-10 John M. Porter , Rene D. Oudmaijer , Debbie Baines

The MOST, CoRoT, and Kepler space missions led to the discovery of a large number of intriguing, and in some cases unique, objects among which are pulsating stars, stars hosting exoplanets, binaries, etc. Although the space missions deliver…

Solar and Stellar Astrophysics · Physics 2015-06-17 A. Tkachenko , T. Van Reeth , V. Tsymbal , C. Aerts , O. Kochukhov , J. Debosscher

Spectrograph slit is conventionally used to enhance the spectral resolution and manage how much light can be allowed to enter spectrograph. A narrower slit provides a higher resolution but sacrifices efficiency of spectrograph and results…

Instrumentation and Methods for Astrophysics · Physics 2013-06-10 FengFei Wang , HaoTong Zhang , A-Li Luo , ZhongRui Bai , Bing Du , YongHeng Zhao

In weak lensing investigations, galaxy shapes are deconvolved for the effects of the point spread function (PSF) using stellar images. In this paper we use physical models of the telescope optics to understand the spatial variation of the…

Astrophysics · Physics 2008-10-02 Mike Jarvis , Paul Schechter , Bhuvnesh Jain

The accurate modelling of the Point Spread Function (PSF) is of paramount importance in astronomical observations, as it allows for the correction of distortions and blurring caused by the telescope and atmosphere. PSF modelling is crucial…

Instrumentation and Methods for Astrophysics · Physics 2023-09-25 Tobias Liaudat , Jean-Luc Starck , Martin Kilbinger

Reconstruction of the point spread function (PSF) plays an important role in many areas of astronomy, including photometry, astrometry, galaxy morphology, and shear measurement. The atmospheric and instrumental effects are the two main…

Instrumentation and Methods for Astrophysics · Physics 2024-04-25 Pedro Alonso , Jun Zhang , Cong Liu

We present a simple, effective approach for estimating the on-order backgrounds of spectra taken with the highest-resolution modes of the Space Telescope Imaging Spectrograph (STIS) on-board the Hubble Space Telescope. Our scheme for…

Astrophysics · Physics 2009-10-31 J. Christopher Howk , Kenneth R. Sembach

The spectral region around 10 micrometer, showing prominent dust emission bands, is commonly used to derive the chemical composition of protoplanetary dust. Different analysis methods have been proposed for this purpose, but so far, no…

Earth and Planetary Astrophysics · Physics 2014-11-18 Attila Juhasz , Thomas Henning , Jeroen Bouwman , Cornelis Dullemond , Ilaria Pascucci , Daniel Apai

We investigate the ellipticity of the point-spread function (PSF) produced by imaging an unresolved source with a telescope, subject to the effects of atmospheric turbulence. It is important to quantify these effects in order to understand…

Astrophysics · Physics 2011-02-11 W. H. de Vries , S. S. Olivier , S. J. Asztalos , L. J. Rosenberg , K. L. Baker

We present STARRED, a Point Spread Function (PSF) reconstruction, two-channel deconvolution, and light curve extraction method designed for high-precision photometric measurements in imaging time series. An improved resolution of the data…

Instrumentation and Methods for Astrophysics · Physics 2024-07-25 Martin Millon , Kevin Michalewicz , Frédéric Dux , Frédéric Courbin , Philip J. Marshall