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We present the development of a data-driven, AI-based model of the Point Spread Function (PSF) that achieves higher accuracy than the current state-of-the-art approach, "PSF in the Full Field-of-View'' (PIFF). PIFF is widely used in leading…

Instrumentation and Methods for Astrophysics · Physics 2026-02-18 Dayana Andrea Henao Arbeláez , Pierre-François Léget , Andrés Alejandro Plazas Malagón

One of the possible approaches to detecting optical counterparts of GRBs requires monitoring large parts of the sky. This idea has gained some instrumental support in recent years, such as with the "Pi of the Sky" project. The broad sky…

Modeling the Point Spread Function (PSF) of wide-field surveys is vital for many astrophysical applications and cosmological probes including weak gravitational lensing. The PSF smears the image of any recorded object and therefore needs to…

Instrumentation and Methods for Astrophysics · Physics 2018-07-26 Jörg Herbel , Tomasz Kacprzak , Adam Amara , Alexandre Refregier , Aurelien Lucchi

Point-spread function (PSF) estimation in spatially undersampled images is challenging because large pixels average fine-scale spatial information. This is problematic when fine-resolution details are necessary, as in optimal photometry…

Instrumentation and Methods for Astrophysics · Physics 2021-02-03 Teresa Symons , Michael Zemcov , James Bock , Yun-Ting Cheng , Brendan Crill , Christopher Hirata , Stephanie Venuto

We present the result of a systematic study of pileup phenomena seen in the X-ray Imaging Spectrometer, an X-ray CCD instrument, onboard the Suzaku observatory. Using a data set of observed sources in a wide range of brightness and spectral…

We present revised point-spread functions (PSFs) for the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). These PSFs provide a robust estimate of the light diffracted by the meshes holding the entrance and…

Solar and Stellar Astrophysics · Physics 2025-02-26 Stefan Hofmeister , Daniel Wolf Savin , Michael Hahn

We make the in-orbit calibration to the point-spread functions (PSFs) of the collimators of the Hard X-ray Modulation Telescope with the scanning observation of the Crab. We construct the empirical adjustments to the theoretically…

Instrumentation and Methods for Astrophysics · Physics 2020-02-05 Yi Nang , Jin-Yuan Liao , Na Sai , Chen Wang , Ju Guan , Cheng-Kui Li , Cheng-Cheng Guo , Yuan Liu , Jing Jin , Xiao-Bo Li , Shu Zhang , Shuang-Nan Zhang

Field distortion is widespread in imaging systems. If it cannot be measured and corrected well, it will affect the accuracy of photogrammetry. To this end, we proposed a general field distortion model based on Fredholm integration, which…

Image and Video Processing · Electrical Eng. & Systems 2022-05-19 Yunqi Sun , Jianfeng Zhou

The use of strongly bent crystals in spectrometers for pulses of a hard x-ray free-electron laser is explored theoretically. Diffraction is calculated in both dynamical and kinematical theories. It is shown that diffraction can be treated…

Instrumentation and Detectors · Physics 2019-05-28 Vladimir Kaganer , Ilia Petrov , Liubov Samoylova

Spectropolarimetry from the near IR to the far UV of light scattered by dust provides a valuable diagnostic of the dust composition, grain size distribution and spatial distribution. To facilitate the use of this diagnostic, we present…

Astrophysics · Physics 2009-10-31 Victor G. Zubko , Ari Laor

Reconstruction of the point spread function (PSF) is a critical process in weak lensing measurement. We develop a real-data based and galaxy-oriented pipeline to compare the performances of various PSF reconstruction schemes. Making use of…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-24 Tianhuan Lu , Jun Zhang , Fuyu Dong , Yingke Li , Dezi Liu , Liping Fu , Guoliang Li , Zuhui Fan

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

Fluorescence imaging is an essential diagnostic tool in many fields, but diffraction-limited optical imaging at depth is limited by scattering. Here, we present a method based on multiple random illuminations, combined with a computational…

Optics · Physics 2026-03-30 Lei Zhu , Tengfei Wu , Bernhard Rauer , Hilton B. de Aguiar , Sylvain Gigan

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

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

Fresnel theory is used to derive the complex electric-fields above and below an X-ray reflecting interface that separates two materials with differing indices of refraction. The interference between the incident and reflected waves produces…

Materials Science · Physics 2009-08-17 Michael J. Bedzyk

Elemental mapping images can be achieved through step scanning imaging using pinhole optics or micro pore optics (MPO), or alternatively by full-field X-ray fluorescence imaging (FF-XRF). X-ray optics for FF-XRF can be manufactured with…

Image and Video Processing · Electrical Eng. & Systems 2023-01-25 Siwen An , David Krapohl , Benny Thörnberg , Romain Roudot , Emile Schyns , Börje Norlin

One of the most important parameters defining the angular resolution of an X-ray optical module is its Half-Energy Width (HEW) as a function of the photon energy. Future X-ray telescopes with imaging capabilities (SIMBOL-X, Constellation-X,…

Instrumentation and Methods for Astrophysics · Physics 2015-09-10 D. Spiga

We develop a comprehensive approach to simulate the deformation of mirrors and lenses due to thermal and mechanical stresses that couples efficiently to photon-based optics simulations. This expands upon previous work where we demonstrated…

Instrumentation and Methods for Astrophysics · Physics 2019-03-20 J. R. Peterson , E. Peng , C. J. Burke , G. Sembroski , J. Cheng

The convolution of galaxy images by the point-spread function (PSF) is the dominant source of bias for weak gravitational lensing studies, and an accurate estimate of the PSF is required to obtain unbiased shape measurements. The PSF…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-16 Martin Eriksen , Henk Hoekstra
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