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Digital aberration measurement and removal play a prominent role in computational imaging platforms aimed at achieving simple and compact optical arrangements. A recent important class of such platforms is Fourier ptychography, which is…

Fabry-P\'erot interferometers (FPIs) have become very popular in solar observations because they offer a balance between cadence, spatial resolution, and spectral resolution through a careful design of the spectral sampling scheme according…

Solar and Stellar Astrophysics · Physics 2023-05-03 C. J. Díaz Baso , L. Rouppe van der Voort , J. de la Cruz Rodríguez , J. Leenaarts

The integral-field unit (IFU) spectrometers on board the James Webb Space Telescope (JWST) undersample the nearly diffraction-limited point spread function provided by the telescope optics. This undersampling produces large oscillating…

Instrumentation and Methods for Astrophysics · Physics 2026-03-31 David R. Law , Melanie Clarke

We study the extent to which Milne-Eddington inversions are able to retrieve and characterize the magnetic landscape of the solar poles from observations by the spectropolarimeter onboard Hinode. In particular, we evaluate whether a…

Solar and Stellar Astrophysics · Physics 2023-07-05 Rebecca Centeno , Ivan Milić , Matthias Rempel , Nariaki V. Nitta , Xudong Sun

X-ray polarization is a powerful tool for unveiling the anisotropic characteristics of high-energy celestial objects. We present a novel imaging reconstruction method designed for hard X-ray polarimeters employing a Si CMOS sensor and coded…

Instrumentation and Methods for Astrophysics · Physics 2024-07-09 Tsubasa Tamba , Hirokazu Odaka , Taihei Watanabe , Toshiya Iwata , Tomoaki Kasuga , Atsushi Tanimoto , Satoshi Takashima , Masahiro Ichihashi , Hiromasa Suzuki , Aya Bamba

In this paper we present new optimization strategies for the reconstruction of X-ray images of solar flares by means of the data collected by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). The imaging concept of the…

Instrumentation and Methods for Astrophysics · Physics 2014-06-26 S. Bonettini , M. Prato

In dynamic scenes, images often suffer from dynamic blur due to superposition of motions or low signal-noise ratio resulted from quick shutter speed when avoiding motions. Recovering sharp and clean results from the captured images heavily…

Computer Vision and Pattern Recognition · Computer Science 2022-03-24 Cheng Zhang , Shaolin Su , Yu Zhu , Qingsen Yan , Jinqiu Sun , Yanning Zhang

Context. The Spectrometer/Telescope for Imaging X-rays (STIX) is one of 6 remote sensing instruments on-board Solar Orbiter. It provides hard X-ray imaging spectroscopy of solar flares by sampling the Fourier transform of the incoming flux.…

Astronomical spectropolarimeters can be subject to many sources of systematic error which limit the precision and accuracy of the instrument. We present a calibration method for observing high-resolution polarized spectra using chromatic…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 D. M. Harrington , J. R. Kuhn , C. Sennhauser , E. J. Messersmith , R. J. Thornton

In this paper, we investigate the impact of survey strategy on the performance of self-calibration when the goal is to produce accurate photometric catalogs from wide-field imaging surveys. This self-calibration technique utilizes multiple…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Rory Holmes , David W. Hogg , Hans-Walter Rix

Spectrographs nominally contain a degree of quasi-static optical aberrations resulting from the quality of manufactured component surfaces, imperfect alignment, design residuals, thermal effects, and other other associated phenomena…

Instrumentation and Methods for Astrophysics · Physics 2021-07-28 Eric B. Bechter , Andrew J. Bechter , Justin R. Crepp , Jonathan Crass

Scanning probe microscopy (SPM) is ubiquitous in nanoscale science allowing the observation of features in real space down to the angstrom resolution. The scanning nature of SPM, wherein a sharp tip rasters the surface during which a…

Instrumentation and Detectors · Physics 2024-11-20 Maxime Le Ster , Sławomir Pawłowski , Iaroslav Lutsyk , Paweł Janusz Kowalczyk

High-contrast imaging presents us with the opportunity to study circumstellar disks and the planets still embedded within them -- providing key insights into the formation and evolution of planetary systems. However, the post-processing…

Earth and Planetary Astrophysics · Physics 2022-08-31 Kellen Lawson , Thayne Currie , John Wisniewski , Tyler Groff , Michael McElwain , Joshua Schlieder

This paper investigates the possibility of improving radio interferometric images using an algorithm inspired by an optical method known as "lucky imaging", which would give more weight to the best-calibrated visibilities used to make a…

Instrumentation and Methods for Astrophysics · Physics 2018-07-18 Etienne Bonnassieux , Cyril Tasse , Oleg Smirnov , Philippe Zarka

We investigate a region of the quiet solar photosphere exhibiting three-lobed Stokes V profiles in the Fe I spectral line at 15648 Angstroem. The data were acquired with the GRIS spectropolarimeter attached to the GREGOR telescope. We aim…

Solar and Stellar Astrophysics · Physics 2018-08-29 Christoph Kiess , Juan Manuel Borrero , Wolfgang Schmidt

Aima. To determine to what extent the problem of forward fitting visibilities measured by the Spectrometer/Telescope Imaging X-rays (STIX) on-board Solar Orbiter is more challenging with respect to the same problem in the case of previous…

In multi-photon microscopy (MPM), a recent in-vivo fluorescence microscopy system, the task of image restoration can be decomposed into two interlinked inverse problems: firstly, the characterization of the Point Spread Function (PSF) and…

Image and Video Processing · Electrical Eng. & Systems 2024-11-08 Julien Ajdenbaum , Emilie Chouzenoux , Claire Lefort , Ségolène Martin , Jean-Christophe Pesquet

The Herschel SPIRE instrument consists of an imaging photometric camera and an imaging Fourier Transform Spectrometer (FTS), both operating over a frequency range of 450-1550 GHz. In this paper, we briefly review the FTS design, operation,…

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

The direct detection of circumstellar discs through high-contrast imaging provides key insights into the history and dynamics of planetary systems. Pole-on discs, especially faint debris discs, are difficult to detect and require careful…

Earth and Planetary Astrophysics · Physics 2025-09-04 S. Stasevic , J. Milli , J. Mazoyer , A. -M. Lagrange , S. Bergeon
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