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Related papers: Segmentation of Loops from Coronal EUV Images

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We present the first reconstruction of the three-dimensional shape of magnetic loops in an active region from two different vantage points based on simultaneously recorded images. The images were taken by the two EUVI telescopes of the…

Astrophysics · Physics 2008-02-07 L. Feng , B. Inhester , S. K. Solanki , T. Wiegelmann , B. Podlipnik , R. A. Howard , J. -P. Wuelser

Active region EUV loops are believed to trace a subset of magnetic field lines through the corona. Malanushenko et al. (2009) proposed a method, using loop images and line-of-sight photospheric magnetograms, to infer the three-dimensional…

Solar and Stellar Astrophysics · Physics 2021-05-27 Marika I. McCarthy , Dana W. Longcope , Anna Malanushenko

Extracting the temperature of coronal loops is effective in the analysis of solar active region's loops and helps in better understanding of coronal events. To this end, various methods have already been developed like the method developed…

Solar and Stellar Astrophysics · Physics 2019-08-30 Narges Fathalian

Coronal holes (CHs) are magnetically open regions that allow hot coronal plasma to escape from the Sun and form the high-speed solar wind. This wind can interact with Earth's magnetic field. For this reason, developing an accurate…

Solar and Stellar Astrophysics · Physics 2025-09-16 Jeremy A. Grajeda , Laura E. Boucheron , Michael S. Kirk , Andrew Leisner , C. Nick Arge , Jaime A. Landeros

Network loops are a common feature in the quiet Sun. The physical processes sustaining their energy budget is still under discussion. We rely on a multi-instrumental (Solar Orbiter/EUI, Solar Orbiter/PHI, IRIS) observation of a six hours…

Solar and Stellar Astrophysics · Physics 2026-03-31 A. Dolliou , H. Peter , S. Mandal , L. P. Chitta , L. Teriaca , Y. Chen , D. Calchetti

Coronal holes are the source regions of the fast solar wind, which fills most of the solar system volume near the cycle minimum. Removing stray light from extreme ultraviolet (EUV) images of the Sun's corona is of high astrophysical…

Solar and Stellar Astrophysics · Physics 2013-02-05 Paul Shearer , Richard A. Frazin , Alfred O. Hero , Anna C. Gilbert

We demonstrate the use of machine learning algorithms in combination with segmentation techniques in order to distinguish coronal holes and filaments in SDO/AIA EUV images of the Sun. Based on two coronal hole detection techniques…

Previous studies have found that coronal loops have a nearly uniform thickness, which seems to disagree with the characteristic expansion of active region magnetic fields. This is one of the most intriguing enigmas in solar physics. We here…

Astrophysics · Physics 2009-11-13 M. C. Lopez Fuentes , J. A. Klimchuk , P. Demoulin

We test the feasibility of 3D coronal-loop tracing in stereoscopic EUV image pairs, with the ultimate goal of enabling efficient 3D reconstruction of the coronal magnetic field that drives flares and coronal mass ejections (CMEs). We…

Solar and Stellar Astrophysics · Physics 2015-11-04 Markus J. Aschwanden , Carolus J. Schrijver , Anna Malanushenko

We developed an automated pattern recognition code that is particularly well suited to extract one-dimensional curvi-linear features from two-dimensional digital images. A former version of this {\sl Oriented Coronal CUrved Loop Tracing…

Solar and Stellar Astrophysics · Physics 2013-08-05 Markus J. Aschwanden , Bart De Pontieu , Eugene A. Katrukha

We propose and test a wavelet transform modulus maxima method for the au- tomated detection and extraction of coronal loops in extreme ultraviolet images of the solar corona. This method decomposes an image into a number of size scales and…

Solar and Stellar Astrophysics · Physics 2010-02-17 R. T. James McAteer , Pierre Kestener , Alain Arneodo , Andre Khalil

We present the observations of an extreme-ultraviolet (EUV) wave, which originated from the active region (AR) NOAA 12887 on 28 October 2021 and its impact on neighbouring loops. The event was observed by the Atmospheric Imaging Assembly…

Solar and Stellar Astrophysics · Physics 2022-12-21 Pooja Devi , Ramesh Chandra , Arun Kumar Awasthi , Brigitte Schmieder , Reetika Joshi

Due to their characteristic temperature and density, loop structures in active regions (ARs) can be seen bright in extreme ultraviolet (EUV) and soft X-ray images. The semiempirical determination of the three-dimensional (3D) distribution…

Solar and Stellar Astrophysics · Physics 2020-12-16 F. A. Nuevo , C. Mac Cormack , M. López Fuentes , A. M. Vásquez , C. H. Mandrini

The identification of large numbers of localised transient EUV brightenings, with small spatial scales, in the quiet-Sun corona has been one of the key early results from Solar Orbiter. However, much is still unknown about these events.…

The variation of the vector magnetic field along structures in the solar corona remains unmeasured. Using a unique combination of spectropolarimetry and stereoscopy, we infer and compare the vector magnetic field structure and…

Solar and Stellar Astrophysics · Physics 2016-12-14 Thomas A. Schad , Matthew J. Penn , Haosheng Lin , Philip G. Judge

The High Resolution Imager (HRI_EUV) telescope of the Extreme Ultraviolet Imager (EUI) instrument onboard Solar Orbiter has observed EUV brightenings, so-called campfires, as fine-scale structures at coronal temperatures. The goal of this…

Solar and Stellar Astrophysics · Physics 2022-10-18 Krzysztof Barczynski , Karen A. Meyer , Louise K. Harra , Duncan H. Mackay , Frederic Auchere , David Berghmans

We describe a method for the automatic mapping of coronal holes (CH) using simultaneous multi-instrument EUV imaging data. Synchronized EUV images from STEREO/EUVI A&B 195A and SDO/AIA 193A are preprocessed, including PSF deconvolution and…

Solar and Stellar Astrophysics · Physics 2016-05-26 R. M. Caplan , C. Downs , J. L. Linker

We performed for the first time stereoscopic triangulation of coronal loops in active regions over the entire range of spacecraft separation angles ($\alpha_{sep}\approx 6^\circ, 43^\circ, 89^\circ, 127^\circ$, and $170^\circ$). The…

Solar and Stellar Astrophysics · Physics 2015-06-05 Markus J. Aschwanden , Jean-Pierre Wülser , Nariaki Nitta , James Lemen

Coronal holes (CH) are regions of open magnetic field lines in the solar corona and the source of fast solar wind. Understanding the evolution of coronal holes is critical for solar magnetism as well as for accurate space weather forecasts.…

Space Physics · Physics 2018-05-02 Amr Hamada , Timo Asikainen , Ilpo Virtanen , Kalevi Mursula

A previous work of ours found the best agreement between EUV light curves observed in an active region core (with evidence of super-hot plasma) and those predicted from a model with a random combination of many pulse-heated strands with a…

Solar and Stellar Astrophysics · Physics 2016-01-27 E. Tajfirouze , F. Reale , G. Peres , P. Testa
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