English
Related papers

Related papers: Automated Coronal Hole Identification via Multi-Th…

200 papers

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

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…

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

An application of active contours without edges is presented as an efficient and effective means of extracting and characterizing coronal holes. Coronal holes are regions of low-density plasma on the Sun with open magnetic field lines. As…

Solar and Stellar Astrophysics · Physics 2016-10-05 L. E. Boucheron , M. Valluri , R. T. J. McAteer

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

We identify coronal holes using a histogram-based intensity thresholding technique and compare their properties to fast solar wind streams at three different points in the heliosphere. The thresholding technique was tested on EUV and X-ray…

Solar and Stellar Astrophysics · Physics 2009-05-13 Larisza D. Krista , Peter T. Gallagher

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

Coronal holes (CH) emit significantly less at coronal temperatures than quiet-Sun regions (QS), but can hardly be distinguished in most chromospheric and lower transition region lines. A key quantity for the understanding of this phenomenon…

Astrophysics · Physics 2009-06-25 T. Wiegelmann , S. K. Solanki

Coronal holes are large-scale structures in the solar atmosphere that feature a reduced temperature and density in comparison to the surrounding quiet Sun and are usually associated with open magnetic fields. We perform a differential…

Solar and Stellar Astrophysics · Physics 2021-03-01 Stephan G. Heinemann , Jonas Saqri , Astrid M. Veronig , Stefan J. Hofmeister , Manuela Temmer

Solar image analysis relies on the detection of coronal holes for predicting disruptions to earth's magnetic field. The coronal holes act as sources of solar wind that can reach the earth. Thus, coronal holes are used in physical models for…

Solar and Stellar Astrophysics · Physics 2022-07-21 Venkatesh Jatla

Through its magnetic activity, the Sun governs the conditions in Earth's vicinity, creating space weather events, which have drastic effects on our space- and ground-based technology. One of the most important solar magnetic features…

Solar and Stellar Astrophysics · Physics 2022-05-18 Fadil Inceoglu , Yuri Y. Shprits , Stephan G. Heinemann , Stefano Bianco

Coronal holes are usually defined as dark structures as seen in the extreme ultraviolet and X-ray spectrum which are generally associated with open magnetic field. Deriving reliably the coronal hole boundary is of high interest, as its…

Identification of solar coronal holes (CHs) provides information both for operational space weather forecasting and long-term investigation of solar activity. Source data for the first problem are typically most recent solar disk…

Solar and Stellar Astrophysics · Physics 2020-11-18 Egor Illarionov , Alexander Kosovichev , Andrey Tlatov

Many scientists use coronal hole (CH) detections to infer open magnetic flux. Detection techniques differ in the areas that they assign as open, and may obtain different values for the open magnetic flux. We characterize the uncertainties…

Coronal holes (CHs) are low-activity, low-density solar coronal regions with open magnetic field lines (Cranmer 2009). In the extreme ultraviolet (EUV) spectrum, CHs appear as dark patches. Using daily hand-drawn maps from the Space Weather…

Instrumentation and Methods for Astrophysics · Physics 2025-11-19 Cutter Beck , Evan Smith , Khagendra Katuwal , Rudra Kafle , Jacob Whitehill

The paper presents the results from a multi-year effort to develop and validate image processing methods for selecting the best physical models based on solar image observations. The approach consists of selecting the physical models based…

Image and Video Processing · Electrical Eng. & Systems 2022-01-06 V. Jatla , M. S. Pattichis , C. N. Arge

Coronal holes are the observational manifestation of the solar magnetic field open to the heliosphere and are of pivotal importance for our understanding of the origin and acceleration of the solar wind. Observations from space missions…

The detection and analysis of the solar coronal holes (CHs) is an important field of study in the domain of solar physics. Mainly, it is required for the proper prediction of the geomagnetic storms which directly or indirectly affect…

Solar and Stellar Astrophysics · Physics 2024-03-28 Sanmoy Bandyopadhyay , Suman Kundu

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…

Coronal holes (CHs) regions are dark in comparison to the quiet-Sun (QS) at the coronal temperatures. However, at chromospheric and transition region (TR) temperatures, QS and CHs are hardly distinguishable. In this study we have used the…

Solar and Stellar Astrophysics · Physics 2018-11-21 Pradeep Kayshap , Durgesh Tripathi , Sami K. Solanki , Hardi Peter
‹ Prev 1 2 3 10 Next ›