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Related papers: On the continuum intensity distribution of the sol…

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We present the initial results of an observational study into the variation of the dominant length-scale of quiet solar emission: supergranulation. This length-scale reflects the radiative energy in the plasma of the upper solar…

Solar and Stellar Astrophysics · Physics 2015-05-27 Scott W. McIntosh , Robert J. Leamon , Rachel A. Hock , Mark P. Rast , Roger K. Ulrich

Continuum emission from a solar flare observed with the Extreme ultraviolet Imaging Spectrometer (EIS) on board the Hinode satellite is used to obtain the radiometric calibration of the instrument. The flare had a GOES class of M8, and…

Solar and Stellar Astrophysics · Physics 2026-05-07 Peter R. Young , Biswajit Mondal

We report a point spread function (PSF) and deconvolution procedure to remove stray light from the Helioseismic and Magnetic Imager (HMI) data. Pre-launch calibration observations, post-launch Venus transit and lunar transit data were used…

Solar and Stellar Astrophysics · Physics 2025-11-18 A. A. Norton , T. L. Duvall, , J. Schou , R. S. Bogart , J. Zhao , C. Rabello-Soares , P. J. Levens , J. T. Hoeksema , C. S. Baldner

We present the point-spread function (PSF) of the Extreme Ultraviolet High-Resolution Imager (HRIEUV) onboard Solar Orbiter, which observes the Sun at 174 Angstrom. This PSF provides a quantitative description of light diffracted by the…

We have carried out numerical simulation based on the equations of radiation magnetohydrodynamics to study the interaction of solar granules and small-scale magnetic fields in photospheric regions with various magnetic fluxes. Four…

Solar and Stellar Astrophysics · Physics 2010-11-09 I. N. Atroshchenko , V. A. Sheminova

In order to assure a stable series of recorded images of sufficient quality for further scientific analysis, an objective image quality measure is required. Especially when dealing with ground-based observations, which are subject to…

Solar and Stellar Astrophysics · Physics 2020-11-11 Robert Jarolim , Astrid Veronig , Werner Pötzi , Tatiana Podladchikova

The irradiance of the Sun is modulated on all time scales. Small-scale solar magnetic elements composed of quiet-Sun network and active region plages contribute to this modulation on solar cycle time scales. The evaluation of their contrast…

Solar and Stellar Astrophysics · Physics 2021-09-02 Fatima Kahil

Hydrodynamic simulations of granular convection predict the existence of supersonic flows covering ~3-4% of the solar surface at any time, but these flows have not been detected unambigously as yet. Using data from the spectropolarimeter…

Solar and Stellar Astrophysics · Physics 2009-07-22 L. R. Bellot Rubio

The observations of solar photosphere from the ground encounter significant problems due to the presence of Earth's turbulent atmosphere. Prior to applying image reconstruction techniques, the frames obtained in most favorable atmospheric…

Instrumentation and Methods for Astrophysics · Physics 2017-12-20 Adam Popowicz , Krystian Radlak , Krzysztof Bernacki , Valeri Orlov

Although the magnetic fields in the quiet Sun account for the majority of the magnetic energy in the solar photosphere, inferring their exact spatial distribution, origin, and evolution poses an important challenge because the signals lie…

Solar and Stellar Astrophysics · Physics 2024-10-03 Elias Ebert , Ivan Milic , Juan Manuel Borrero

Reduction of images and science analysis from ground-based telescopes such as the LSST requires detailed knowledge of the PSF of the image, which includes components attributable to the instrument as well as components attributable to the…

Instrumentation and Methods for Astrophysics · Physics 2017-04-26 Craig Lage , Andrew Bradshaw , J. Anthony Tyson

Solar wind turbulence is often perceived as weakly compressible and the density fluctuations remain poorly understood both theoretically and observationally. Compressible magnetohydrodynamic simulations provide useful insights into the…

Space Physics · Physics 2023-04-12 Senbei Du , Hui Li , Zhaoming Gan , Xiangrong Fu

The weak, turbulent magnetic fields that supposedly permeate most of the solar photosphere are difficult to observe, because the Zeeman effect is virtually blind to them. The Hanle effect, acting on the scattering polarization in suitable…

Solar and Stellar Astrophysics · Physics 2015-05-19 F. Snik , A. G. de Wijn , K. Ichimoto , C. E. Fischer , C. U. Keller , B. W. Lites

A parametric model of granulation employing a small number of parameters was developed. Synthetic spectra calculated using this model closely match observed spectra and, in particular, reproduce the asymmetries observed in spectral lines.…

Solar and Stellar Astrophysics · Physics 2017-08-23 Timo A. Nieminen

Solar granules are bright patterns surrounded by dark channels called intergranular lanes in the solar photosphere and are a manifestation of overshooting convection. Observational studies generally find stronger upflows in granules and…

Solar and Stellar Astrophysics · Physics 2017-11-01 T. Oba , T. L. Riethmüller , S. K. Solanki , Y. Iida , C. Quintero Noda , T. Shimizu

We performed a 3D radiative MHD simulation of the solar atmosphere. This simulation shows a jet-like feature that shows similarities to the type II spicules observed for the first time with Hinode. Rapid Blueshifted Events (RBEs) on the…

The chromosphere of the quiet Sun is a highly intermittent and dynamic phenomenon. Three-dimensional radiation (magneto-)hydrodynamic simulations exhibit a mesh-like pattern of hot shock fronts and cool expanding post-shock regions in the…

Astrophysics · Physics 2009-11-13 Sven Wedemeyer-Böhm , Friedrich Wöger

This paper investigates the conditions for producing rapid variations of solar ener- getic particle (SEP) intensity commonly known as dropouts. In particular, we use numerical model simulations based on solving the focused transport…

Solar and Stellar Astrophysics · Physics 2015-06-19 Y. Wang , G. Qin , M. Zhang , S. Dalla

The number of satellites on low orbit has dramatically increased over the past years, raising concerns among the astronomical community about their impact on observations. Spectroscopic observations represent a large fraction of…

Instrumentation and Methods for Astrophysics · Physics 2024-01-19 Olivier R. Hainaut Sabine Moehler

Results from initial helioseismic observations by Solar Optical Telescope onboard Hinode are reported. It has been demonstrated that intensity oscillation data from Broadband Filter Imager can be used for various helioseismic analyses. The…