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Related papers: Segmentation of Loops from Coronal EUV Images

200 papers

Coronal loops are plasma structures in the solar atmosphere with temperatures reaching millions of Kelvin, shaped and sustained by the magnetic field. However, their morphology and fundamental nature remain subjects of debate. By studying…

Solar and Stellar Astrophysics · Physics 2026-01-14 N. Vasantharaju , H. Peter , L. P. Chitta , S. Mandal

The 3D magnetic topology of a solar active region (NOAA 10956) was reconstructed using a linear force-free field extrapolation constrained using the twin perspectives of \emph{STEREO}. A set of coronal field configurations was initially…

Solar and Stellar Astrophysics · Physics 2015-05-18 Paul A. Conlon , Peter T. Gallagher

Precise localisation and characterization of active regions and coronal holes as observed by EUV imagers are crucial for a wide range of solar and helio-physics studies. We describe a segmentation procedure, the SPOCA-suite, that produces…

Instrumentation and Methods for Astrophysics · Physics 2012-08-08 Véronique Delouille , Benjamin Mampaey , Cis Verbeeck , Ruben de Visscher

Recent progress in obtaining high spatial resolution images of the solar corona in the extreme-ultraviolet (EUV) with Hinode, TRACE, SDO and recent Hi-C missions and soft X-ray (SXR) bands opened a new avenue in understanding the solar…

Solar and Stellar Astrophysics · Physics 2014-09-16 V. S. Airapetian , J. Allred

Coronal loops, seen in solar coronal images, are believed to represent emission from magnetic flux tubes with compact cross-sections. We examine the 3D structure of plasma above an active region in a radiative magnetohydrodynamic simulation…

Solar and Stellar Astrophysics · Physics 2022-03-09 A. Malanushenko , M. C. M. Cheung , C. E. DeForest , J. A. Klimchuk , M. Rempel

We report for the first time the detection of thermal free-free emission from post-flare loops at 34GHz in images from the Nobeyama Radioheliograph (NoRH). We studied 8 loops, 7 of which were from regions with extremely strong coronal…

Solar and Stellar Astrophysics · Physics 2024-06-24 Costas E. Alissandrakis , Gregory D. Fleishman , Viktor V. Fedenev , Stephen M. White , Alexander T. Altyntsev

The \textit{Sun Watcher using Active Pixel system detector and Image Processing}(SWAP) on board the \textit{PRoject for OnBoard Autonomy\todash 2} (PROBA\todash 2) spacecraft provides images of the solar corona in EUV channel centered at…

Solar and Stellar Astrophysics · Physics 2012-06-11 K. Chandrashekhar , S. Krishna Prasad , D. Banerjee , B. Ravindra , Daniel B. Seaton

Standard visualizations of Extreme Ultraviolet (EUV) solar imagery often fail to convey the full complexity of the Sun's corona, especially in faint off-limb regions. This can leave the misleading impression of the Sun as a bright ball in a…

Solar and Stellar Astrophysics · Physics 2025-11-05 Chris Gilly , Steven Cranmer

Observations from the two STEREO-spacecraft give us for the first time the possibility to use stereoscopic methods to reconstruct the 3D solar corona. Classical stereoscopy works best for solid objects with clear edges. Consequently an…

Solar and Stellar Astrophysics · Physics 2015-05-14 T. Wiegelmann , B. Inhester , L. Feng

Magnetic field extrapolation is an important tool to study the three-dimensional (3D) solar coronal magnetic field which is difficult to directly measure. Various analytic models and numerical codes exist but their results often drastically…

Solar and Stellar Astrophysics · Physics 2017-06-28 Aiying Duan , Chaowei Jiang , Qiang Hu , Huai Zhang , G. Allen Gary , S. T. Wu , Jinbin Cao

Many edge and contour detection algorithms give a soft-value as an output and the final binary map is commonly obtained by applying an optimal threshold. In this paper, we propose a novel method to detect image contours from the extracted…

Computer Vision and Pattern Recognition · Computer Science 2021-05-12 Zahra Mousavi Kouzehkanan , Reshad Hosseini , Babak Nadjar Araabi

Understanding the relationship between the magnetic field and coronal heating is one of the central problems of solar physics. However, studies of the magnetic properties of impulsively heated loops have been rare. We present results from a…

Solar and Stellar Astrophysics · Physics 2019-06-12 Ignacio Ugarte-Urra , Nicholas A. Crump , Harry P. Warren , Thomas Wiegelmann

Microscopy with extreme ultraviolet (EUV) radiation holds promise for high-resolution imaging with excellent material contrast, due to the short wavelength and numerous element-specific absorption edges available in this spectral range. At…

Decaying active region 10942 is investigated from 4:00-16:00 UT on February 24, 2007 using a suite of EUV observing instruments. Results from Hinode/EIS, STEREO and TRACE show that although the active region has decayed and no sunspot is…

Solar and Stellar Astrophysics · Physics 2015-05-30 Jason Scott , P. C. H. Martens , David McKenzie

We used data from the Helioseismic and Magnetic Imager (HMI), and Atmospheric Imaging Assembly (AIA) on the \textit{Solar Dynamics Observatory} (SDO) to study coronal loops at small scales, emerging in the quiet Sun. With HMI line-of-sight…

Solar and Stellar Astrophysics · Physics 2013-04-15 LP. Chitta , R. Kariyappa , A. A. van Ballegooijen , E. E. DeLuca , S. S. Hasan , A. Hanslmeier

We analyse imaging (EUV, X-ray) and spectral (radio, X-ray) data obtained by ground based and space instruments on board space missions both on Earth (Fermi, Hinode, Solar Dynamics Observatory) and solar orbit (Solar Orbiter, STEREO-A),…

In this study we have compared coronal loops in the Extreme ultraviolet Imaging Telescope (EIT) on-board the Solar and Heliospheric Observatory (SOHO) with coronal loops from the Transition Region and Coronal Explorer (TRACE). The purpose…

Solar and Stellar Astrophysics · Physics 2017-05-22 S. I. Chastain , J. T. Schmelz

Coronal Holes (CHs) are regions of open magnetic field lines, resulting in high speed solar wind. Accurate detection of CHs is vital for space weather prediction. This paper presents an intramethod ensemble for coronal hole detection based…

Solar and Stellar Astrophysics · Physics 2024-11-08 Jeremy A. Grajeda , Laura E. Boucheron , Michael S. Kirk , Andrew Leisner , C. Nick Arge

X-ray and EUV observations are an important diagnostic of various plasma parameters of the solar atmosphere during solar flares. Soft X-ray and EUV observations often show coronal sources near the top of flaring loops, while hard X-ray…

Solar and Stellar Astrophysics · Physics 2015-06-11 Marina Battaglia , Eduard P. Kontar

The theoretical expectation that coronal loops should expand with height contrasts with observations that typically show constant cross-sections. We investigate the idea that this discrepancy results from loops being composed of fine…

Solar and Stellar Astrophysics · Physics 2025-12-16 David H. Brooks , Harry P. Warren