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Planned wide-field weak lensing surveys are expected to reduce the statistical errors on the shear field to unprecedented levels. In contrast, systematic errors like those induced by the convolution with the point spread function (PSF) will…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-23 M. Gentile , F. Courbin , G. Meylan

Point Spread Function (PSF) modeling is a central part of any astronomy data analysis relying on measuring the shapes of objects. It is especially crucial for weak gravitational lensing, in order to beat down systematics and allow one to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 Joel Bergé , Sedona Price , Adam Amara , Jason Rhodes

Imaging devices exploit the Nyquist-Shannon sampling theorem to avoid both aliasing and redundant oversampling by design. Conversely, in medical image resampling, images are considered as continuous functions, are warped by a spatial…

Image and Video Processing · Electrical Eng. & Systems 2021-01-19 M. Jorge Cardoso , Marc Modat , Tom Vercauteren , Sebastien Ourselin

In order to enhance accuracy of astrophysical estimates obtained on Adaptive-optics (AO) images, such as photometry and astrometry, we investigate a new concept to constrain the Point Spread Function (PSF) model called PSF Reconstruction…

Instrumentation and Methods for Astrophysics · Physics 2019-06-26 O. Beltramo-Martin , C. M. Correia , S. Ragland , L. Jolissaint , B. Neichel , T. Fusco , P. L. Wizinowich

Point spread function (PSF) reconstruction (PSF-R) is a well established technique to determine reliably and accurately the PSF from Adaptive Optics (AO) control loop data. We have successfully applied this technique to improve the…

Instrumentation and Methods for Astrophysics · Physics 2020-04-15 Olivier Beltramo-Martin , Antonino Marasco , Thierry Fusco , Davide Massari , Julien Milli , Giuliana Fiorentino , B. Neichel

Precise knowledge of the point spread function (PSF) underpins many data analysis steps in astronomy, from photometry and astrometry to source de-blending and deconvolution. In adaptive optics (AO) observations, however, the PSF is highly…

Instrumentation and Methods for Astrophysics · Physics 2026-04-02 Arseniy Kuznetsov , Benoit Neichel , Sylvain Oberti , Thierry Fusco

Our aim is to evaluate fundamental parameters from the analysis of the electromagnetic spectra of stars. We may use $10^3$-$10^5$ spectra; each spectrum being a vector with $10^2$-$10^4$ coordinates. We thus face the so-called "curse of…

Instrumentation and Methods for Astrophysics · Physics 2017-06-08 V. Watson , JF. Trouilhet , F. Paletou , S. Girard

Accurate modelling of redshift-space distortions (RSD) is challenging in the non-linear regime for two-point statistics e.g. the two-point correlation function (2PCF). We take a different perspective to split the galaxy density field…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-14 Enrique Paillas , Yan-Chuan Cai , Nelson Padilla , Ariel Sánchez

We describe the time- and position-dependent point spread function (PSF) variation of the Wide Field Channel (WFC) of the Advanced Camera for Surveys (ACS) with the principal component analysis (PCA) technique. The time-dependent change is…

Astrophysics · Physics 2009-11-13 M. J. Jee , J. P. Blakeslee , M. Sirianni , A. R. Martel , R. L. White , H. C. Ford

Precise photometric and astrometric measurements on astronomical images require an accurate knowledge of the Point Spread Function (PSF). When the PSF cannot be modelled directly from the image, PSF-reconstruction techniques become the only…

Instrumentation and Methods for Astrophysics · Physics 2020-02-05 D. Massari , A. Marasco , O. Beltramo-Martin , J. Milli , G. Fiorentino , E. Tolstoy , F. Kerber

We introduce a new framework for point-spread function (PSF) subtraction based on the spatio-temporal variation of speckle noise in high-contrast imaging data where the sampling timescale is faster than the speckle evolution timescale. One…

Instrumentation and Methods for Astrophysics · Physics 2023-01-23 Briley L. Lewis , Michael P. Fitzgerald , Rupert H. Dodkins , Kristina K. Davis , Jonathan Lin

Here we propose FastFCA-AS, an accelerated algorithm for Full-rank spatial Covariance Analysis (FCA), which is a robust audio source separation method proposed by Duong et al. ["Under-determined reverberant audio source separation using a…

Sound · Computer Science 2018-05-25 Nobutaka Ito , Tomohiro Nakatani

Increasing the imaging speed is a central aim in photoacoustic tomography. This issue is especially important in the case of sequential scanning approaches as applied for most existing optical detection schemes. In this work we address this…

Numerical Analysis · Mathematics 2016-11-23 Markus Haltmeier , Thomas Berer , Sunghwan Moon , Peter Burgholzer

The problem of recovering a mixture of spike signals convolved with distinct point spread functions (PSFs) lying on a parametric manifold, under the assumption that the spike locations are known, is studied. The PSF unmixing problem is…

Signal Processing · Electrical Eng. & Systems 2025-09-30 Santos Michelena , Maxime Ferreira Da Costa , José Picheral

We present a general framework for matching the point-spread function (PSF), photometric scaling, and sky background between two images, a subject which is commonly referred to as difference image analysis (DIA). We introduce the new…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 D. M. Bramich , Keith Horne , M. D. Albrow , Y. Tsapras , C. Snodgrass , R. A. Street , M. Hundertmark , Noe Kains , A. Arellano Ferro , R. Figuera Jaimes , Sunetra Giridhar

Current measurements of the weak lensing signal induced by large scale structure provide useful constraints on a range of cosmological parameters. However, the ultimate succes of this technique depends on the accuracy with which one can…

Astrophysics · Physics 2009-11-07 Henk Hoekstra

We present a new technique for monitoring microlensing activity even in highly crowded fields, and use this technique to place limits on low-mass MACHOs in the haloes of M31 and the Galaxy. Unlike present Galactic microlensing surveys, we…

Astrophysics · Physics 2009-09-28 Austin B. Tomaney , Arlin P. S. Crotts

Ultrasound imaging systems rely on accurate point spread function (PSF) estimation to support advanced image quality enhancement techniques such as deconvolution and speckle reduction. Phase aberration, caused by sound speed inhomogeneity…

Signal Processing · Electrical Eng. & Systems 2025-02-24 Wei-Hsiang Shen , Yu-An Lin , Meng-Lin Li

Video synthetic aperture radar (SAR) is attracting more attention in recent years due to its abilities of high resolution, high frame rate and advantages in continuous observation. Generally, the polar format algorithm (PFA) is an efficient…

Computer Vision and Pattern Recognition · Computer Science 2024-01-22 Jiawei Jiang , Yinwei Li , Shaowen Luo , Ping Li , Yiming Zhu

In preparation of future Multi-Object Spectrographs (MOS) whose one of the major role is to provide an extensive statistical studies of high redshifted galaxies surveyed, the demonstrator Canary has been designed to tackle technical…

Instrumentation and Methods for Astrophysics · Physics 2016-11-23 O. A. Martin , C. M. Correia , E. Gendron , G. Rousset , D. Gratadour , F. Vidal , T. J. Morris , A. G. Basden , R. M. Myers , B. Neichel , T. Fusco
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