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Related papers: Differencing and Coadding JWST Images with Matched…

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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

Optical astronomical images are strongly affected by the point spread function (PSF) of the optical system and the atmosphere (seeing) which blurs the observed image. The amount of blurring depends both on the observed band, and on the…

Instrumentation and Methods for Astrophysics · Physics 2023-08-31 Hong Wang , Sreevarsha Sreejith , Yuewei Lin , Nesar Ramachandra , Anže Slosar , Shinjae Yoo

Accessing the point-spread function (PSF) of a complex optical system is important for a variety of imaging applications. However, placing an invasive point source is often impractical, and estimating it blindly with multiple frames is slow…

Optics · Physics 2020-09-23 Tengfei Wu , Jonathan Dong , Sylvain Gigan

We report Spitzer 3.6 and 4.5 $\mu$m photometry of 11 bright stars relative to Sirius, exploiting the unique optical stability of the Spitzer Space Telescope point spread function (PSF). Spitzer's extremely stable beryllium optics in its…

Solar and Stellar Astrophysics · Physics 2022-01-12 Kate Y. L. Su , G. H. Rieke , M. Marengo , Everett Schlawin

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

We present a theoretical analysis of the measuring algorithm we use when applying the Diffracto-Astrometry technique to Hubble Space Telescope Wide Field Planetary Camera 2 (WFPC2) saturated stellar images. Theoretical Point Spread…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 A. Ruelas-Mayorga , L. J. Sanchez , J. Olivares , C. Allen , A. Poveda , R. Costero , A. Nigoche-Netro

Deblurring is a fundamental inverse problem in bioimaging. It requires modelling the point spread function (PSF), which captures the optical distortions entailed by the image formation process. The PSF limits the spatial resolution…

Image and Video Processing · Electrical Eng. & Systems 2019-03-04 Denis K. Samuylov , Prateek Purwar , Gábor Székely , Grégory Paul

We present an efficient Bayesian SED-fitting framework tailored to multiwavelength pixel photometry from the JWST Advanced Deep Extragalactic Survey (JADES). Our method employs simulation-based inference to enable rapid posterior sampling…

In this second paper in a series dedicated to developing efficient numerical techniques for the deblurring Cosmic Microwave Background (CMB) maps, we consider the case of asymmetric point spread functions (PSF). Although conceptually this…

Astrophysics · Physics 2009-11-10 R. Vio , J. G. Nagy , L. Tenorio , P. Andreani , C. Baccigalupi , W. Wamsteker

Context: in astronomy, observing large fractions of the sky within a reasonable amount of time implies using large field-of-view (fov) optical instruments that typically have a spatially varying Point Spread Function (PSF). Depending on the…

Computer Vision and Pattern Recognition · Computer Science 2017-03-20 F. M. Ngolè Mboula , J. -L. Starck

Difference imaging is a technique for obtaining precise relative photometry of variable sources in crowded stellar fields and, as such, constitutes a crucial part of the data reduction pipeline in surveys for microlensing events or…

Astrophysics · Physics 2009-11-11 Holger Israel , Frederic V. Hessman , Sonja Schuh

A main science goal for the Large Synoptic Survey Telescope (LSST) is to measure the cosmic shear signal from weak lensing to extreme accuracy. One difficulty, however, is that with the short exposure time ($\simeq$15 seconds) proposed, the…

Imaging with a layered superlens is a spatial filtering operation characterized by the point spread function (PSF). We show that in the same optical system the image of a narrow sub-wavelength Gaussian incident field may be surprisingly…

Optics · Physics 2010-04-08 Rafal Kotynski , Tomasz Stefaniuk

Removing the aberrations introduced by the Point Spread Function (PSF) is a fundamental aspect of astronomical image processing. The presence of noise in observed images makes deconvolution a nontrivial task that necessitates the use of…

Instrumentation and Methods for Astrophysics · Physics 2017-05-03 Samuel Farrens , Jean-Luc Starck , Fred Maurice Ngolè Mboula

We use JWST NIRCam short wavelength photometry to capture a transit lightcurve of the exoplanet HAT-P-14 b to assess performance as part of instrument commissioning. The short wavelength precision is 152 ppm per 27 second integration as…

W projection is a commonly-used approach to allow interferometric imaging to be accelerated by Fast Fourier Transforms (FFTs), but it can require a huge amount of storage for convolution kernels. The kernels are not separable, but we show…

Instrumentation and Methods for Astrophysics · Physics 2016-01-27 Bruce Merry

The point spread function (PSF) of a translation invariant imaging system is its impulse response, which cannot always be measured directly. This is the case in high energy X-ray radiography, and it must be estimated from images of…

Numerical Analysis · Mathematics 2017-09-27 Kevin T. Joyce , Johnathan M. Bardsley , Aaron Luttman

Pansharpening is a significant image fusion technique that merges the spatial content and spectral characteristics of remote sensing images to generate high-resolution multispectral images. Recently, denoising diffusion probabilistic models…

Computer Vision and Pattern Recognition · Computer Science 2024-04-18 Yu Zhong , Xiao Wu , Liang-Jian Deng , Zihan Cao

We study the problem of deconvolution for light-sheet microscopy, where the data is corrupted by spatially varying blur and a combination of Poisson and Gaussian noise. The spatial variation of the point spread function (PSF) of a…

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