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Related papers: Measuring angular diameters of extended sources

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When measuring diameters of partially resolved sources like planetary nebulae, H II regions or galaxies, often a technique called gaussian deconvolution is used. This technique yields a gaussian diameter which subsequently has to be…

Astrophysics · Physics 2007-05-23 P. A. M. van Hoof

A simple Gaussian size deconvolution method is routinely used to remove the blur of observed images caused by insufficient angular resolutions of existing telescopes, thereby to estimate the physical sizes of extracted sources and…

Instrumentation and Methods for Astrophysics · Physics 2023-07-26 Alexander Men'shchikov

A fast and practical method is described for calculating the microlensed flux variance of an arbitrary source by uncorrelated stars. The required inputs are the mean convergence and shear due to the smoothed potential of the lensing galaxy,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Jeremy Goodman , Ai-Lei Sun

We present a new method to derive reliable photometry of extended spherically symmetric sources from {\it HST} images (WFPC2, ACS/WFC and NICMOS/NIC2 cameras), extending existing studies of point sources and marginally resolved sources. We…

Astrophysics · Physics 2012-01-30 P. Anders , M. Gieles , R. de Grijs

Extended source effects can be seen in gravitational lensing events when sources cross critical lines. Those events probe the stellar intensity profile and could be used to measure limb darkening coefficients to test stellar model…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 Hans J. Witt , F. Atrio-Barandela

A method for spatial deconvolution of spectra is presented. It follows the same fundamental principles as the ``MCS image deconvolution algorithm'' (Magain, Courbin, Sohy, 1998) and uses information contained in the spectrum of a reference…

Astrophysics · Physics 2009-10-31 F. Courbin , P. Magain , M. Kirkove , S. Sohy

We introduce a novel method for weak-lensing measurements, which is based on a mathematically exact deconvolution of the moments of the apparent brightness distribution of galaxies from the telescope's PSF. No assumptions on the shape of…

Instrumentation and Methods for Astrophysics · Physics 2012-04-24 Peter Melchior , Massimo Viola , Björn Malte Schäfer , Matthias Bartelmann

In this paper, we propose a novel design of image deblurring in the form of one-shot convolution filtering that can directly convolve with naturally blurred images for restoration. The problem of optical blurring is a common disadvantage to…

Image and Video Processing · Electrical Eng. & Systems 2019-07-22 Mahdi S. Hosseini , Konstantinos N. Plataniotis

We introduce a method to constrain the characteristic angular size of the brightest cosmic-ray sources observed above 57 \times 1018 eV. By angular size of a source, we mean the effective angular extent over which cosmic-rays from that…

High Energy Astrophysical Phenomena · Physics 2011-09-28 Patrick Younk

In this work we derive analytic expressions and numerical recipes for finding the effective observed position of sources close enough on sky that their Point Spread Functions (PSF), modelled as Gaussian profiles, overlap. In particularly we…

Solar and Stellar Astrophysics · Physics 2026-03-24 Zephyr Penoyre

In camera measurement systems, specialized equipment such as telecentric lenses is often employed to measure parts with narrow tolerances. However, despite the use of such equipment, measurement errors can occur due to mechanical and…

Computer Vision and Pattern Recognition · Computer Science 2025-08-11 Ahmet Gokhan Poyraz , Ahmet Emir Dirik , Hakan Gurkan , Mehmet Kacmaz

We studied both theoretically and experimentally the intensity distribution of a Gaussian laser beam when it was focussed by an objective lens with its numerical-aperture (NA) up to 0.95. Approximate formulae for full widths at half maximum…

Strong gravitational lens systems with extended sources are of special interest because they provide additional constraints on the models of the lens systems. To use a gravitational lens system for measuring the Hubble constant, one would…

Astrophysics · Physics 2009-11-11 S. H. Suyu , P. J. Marshall , M. P. Hobson , R. D. Blandford

(Abridged) We present a new method for detecting and measuring compact sources in conditions of intense, and highly variable, fore/background. While all most commonly used packages carry out the source detection over the signal image, our…

Gravitationally lensed extragalactic sources are often subject to statistical microlensing by stars in the galaxy or cluster lens. Accurate models of the flux statistics are required for inferring source and lens properties from flux…

Astrophysics of Galaxies · Physics 2021-04-27 Liang Dai , Massimo Pascale

This paper develops a density deconvolution estimator that assumes the density of interest is a member of the generalized skew-symmetric (GSS) family of distributions. Estimation occurs in two parts: a skewing function, as well as location…

Methodology · Statistics 2017-06-07 Cornelis J. Potgieter

First, we have generalized the notion of Franhoufer diffraction of temporal coherent light from a single slit to the case of arbitrary n-slits. The diffraction pattern is investigated for different values of recently [19] introduced…

Optics · Physics 2023-10-20 E. Koushki , S. A. Alavi

A new method is presented for determining the Point Spread Function (PSF) of images that lack bright and isolated stars. It is based on the same principles as the MCS (Magain, Courbin, Sohy, 1998) image deconvolution algorithm. It uses the…

Astrophysics · Physics 2009-11-11 P. Magain , F. Courbin , M. Gillon , S. Sohy , G. Letawe , V. Chantry , Y. Letawe

Reproducing an all-in-focus image from an image with defocus regions is of practical value in many applications, eg, digital photography, and robotics. Using the output of some existing defocus map estimator, existing approaches first…

Computer Vision and Pattern Recognition · Computer Science 2018-08-29 Guodong Xu , Chaoqiang Liu , Hui Ji

Ground-based astronomical observations will continue to produce resolution-limited images due to atmospheric seeing. Deconvolution reverses such effects and thus can benefit extracted science in multifaceted ways. We apply the Scaled…

Instrumentation and Methods for Astrophysics · Physics 2025-11-04 Yash Gondhalekar , Richard M. Feder , Matthew J. Graham , Ajit K. Kembhavi , Margarita Safonova , Snehanshu Saha , Ashish A. Mahabal
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