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Related papers: Segmentation of Loops from Coronal EUV Images

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One of the major discoveries of the Extreme ultraviolet Imaging Telescope (EIT) on SOHO were intensity enhancements propagating over a large fraction of the solar surface. The physical origin(s) of the so-called `EIT' waves is still…

Solar and Stellar Astrophysics · Physics 2015-05-13 S. Patsourakos , A. Vourlidas , Y. -M. Wang , G. Stenborg , A. Thernisien

Data from recent numerical simulations of the solar corona and transition region are analysed and the magnetic field connection between the low corona and the photosphere is found to be close to that of a potential field. The fieldline to…

Astrophysics · Physics 2014-10-13 B. V. Gudiksen , Å. Nordlund

We study the effect of the coronal background in the determination of the diameter of EUV loops, and we analyze the suitability of the procedure followed in a previous paper (L\'opez Fuentes, Klimchuk & D\'emoulin 2006) for characterizing…

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

Extreme-ultraviolet (EUV) waves are one of the large-scale phenomena on the Sun. They are defined as large propagating fronts in the low corona with speeds ranging from a few tens km/s to a multiple of 1000 km/s. They are often associated…

Solar and Stellar Astrophysics · Physics 2023-10-20 Ramesh Chandra , Pooja Devi , P. F. Chen , Brigitte Schmieder , Reetika Joshi , Bhuwan Joshi , Arun Kumar Awasthi

Intravascular Ultrasound (IVUS) is an intra-operative imaging modality that facilitates observing and appraising the vessel wall structure of the human coronary arteries. Segmentation of arterial wall boundaries from the IVUS images is not…

Computer Vision and Pattern Recognition · Computer Science 2018-06-12 Mehdi Faraji , Irene Cheng , Iris Naudin , Anup Basu

We present preliminary reconstructions of the EUV from 26 to 34\,nm from February 1997 to May 2005, covering most of solar cycle 23. The reconstruction is based on synthetic EUV spectra calculated with the spectral synthesis code Solar…

Solar and Stellar Astrophysics · Physics 2015-06-05 Margit Haberreiter

Previous solar observations have shown that coronal loops near 1 MK are difficult to reconcile with simple heating models. These loops have lifetimes that are long relative to a radiative cooling time, suggesting quasi-steady heating. The…

We search for EUV brightenings in TRACE 171 {\AA} images and HXR bursts observed during failed eruptions. We expect that if an eruption is confined due to interaction with overlying magnetic structures then we should observe effects…

Solar and Stellar Astrophysics · Physics 2015-06-11 A. Netzel , T. Mrozek , S. Kolomanski , S. Gburek

Seismic maps of the Sun's far hemisphere, computed from Doppler data from the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) are now being used routinely to detect strong magnetic regions on the far…

Solar and Stellar Astrophysics · Physics 2017-10-11 P. C. Liewer , J. Qiu , C. Lindsey

Coronal loop observations have existed for many decades yet the precise shape of these fundamental coronal structures is still widely debated since the discovery that they appear to undergo negligible expansion between their footpoints and…

Solar and Stellar Astrophysics · Physics 2021-09-29 Thomas Williams , Robert W. Walsh , Huw Morgan

Coronal Holes (CHs) are large-scale, low-density regions in the solar atmosphere which may expel high-speed solar wind streams that incite hazardous, geomagnetic storms. Coronal and solar wind models can predict these high-speed streams and…

Using detrended fluctuation analysis (DFA) and rescaled range (R/S) analysis, we investigate the scaling properties of EUV intensity fluctuations of low-latitude coronal holes (CHs) and neighboring quiet-Sun (QS) regions in signals obtained…

Solar and Stellar Astrophysics · Physics 2020-01-08 Ana Cristina Cadavid , Mari Paz Miralles , Kristine Romich

There is a pressing need to model X-ray Ultra-Violet (XUV: 1-30 nm) stellar irradiances, given the scarcity of current measurements. One of the measurable effects of a stellar cycle is the significant (more than one order of magnitude)…

Solar and Stellar Astrophysics · Physics 2025-04-14 E. Deliporanidou , G. Del Zanna , T. N. Woods , D. Woodraska

The $\textrm{HRI}_\textrm{EUV}$ telescope was calibrated on ground at the Physikalisch-Technische Bundesanstalt (PTB), Germany's national metrology institute, using the Metrology Light Source (MLS) synchrotron in April 2017 during the…

We investigate the coronal imaging capabilities of the Solar UltraViolet Imager (SUVI) on the Geostationary Operational Environmental Satellite-R series spacecraft. Nominally Sun-pointed, SUVI provides solar images in six Extreme…

Understanding the initiation of solar flares and coronal mass ejections (CMEs) is essential for improving forecasts of extreme space weather. Soft X-ray (SXR) and Extreme Ultraviolet (EUV) observations provide critical diagnostics of the…

One puzzling observed property of coronal loops is that they are of roughly constant thickness along their length. Various studies have found no consistent pattern of width variation along the length of loops observed by TRACE and SOHO.…

Solar and Stellar Astrophysics · Physics 2009-11-13 Joseph E. Plowman , Charles C. Kankelborg , Dana W. Longcope

Current coronal holes segmentation methods typically rely on image thresholding and require non-trivial image pre- and post-processing. We have trained a neural network that accurately isolates CHs from SDO/AIA 193 Angstrom solar disk…

Solar and Stellar Astrophysics · Physics 2018-10-17 E. Illarionov , A. Tlatov

Filaments may be mistaken for coronal holes when observed in extreme ultraviolet (EUV) images; however, a closer and more careful look reveals that their photometric properties are different. The combination of EUV images with photospheric…

Solar and Stellar Astrophysics · Physics 2017-04-04 Judith Palacios , Consuelo Cid , Elena Saiz , Yolanda Cerrato , Antonio Guerrero

This thesis strives to improve our understanding of solar activity, specifically the behaviour of solar flares and coronal mass ejections. An investigation into the hydrodynamic evolution of a confined solar flare was carried out using…

Solar and Stellar Astrophysics · Physics 2012-10-19 Claire L. Raftery