English
Related papers

Related papers: Coronal Cells in Coronal Holes: Systematic Analysi…

200 papers

The interaction of open and closed field lines at coronal hole boundaries is widely accepted to be due to interchange magnetic reconnection. To date, it is unclear how the boundaries vary on short timescales and at what velocity this…

Solar and Stellar Astrophysics · Physics 2015-05-27 Larisza D. Krista , Peter T. Gallagher , D. Shaun Bloomfield

The solar magnetic field is the primary agent that drives solar activity and couples the Sun to the Heliosphere. Although the details of this coupling depend on the quantitative properties of the field, many important aspects of the corona…

Astrophysics · Physics 2009-11-13 S. K. Antiochos , C. R. DeVore , J. T. Karpen , Z. Mikic

We developed a new numerical code that is able to perform 2.5D simulations of a magnetohydrodynamic (MHD) wave propagation in the corona, and its interaction with a low density region, such as a coronal hole (CH). We show that the impact of…

It has long been known that the high-speed stream (HSS) peak velocity at Earth directly depends on the area of the coronal hole (CH) on the Sun. Different degrees of association between the two parameters have been shown by many authors. In…

The solar coronal heating in quiet Sun (QS) and coronal holes (CH), including solar wind formation, are intimately tied by magnetic field dynamics. Thus, a detailed comparative study of these regions is needed to understand the underlying…

Solar and Stellar Astrophysics · Physics 2022-02-23 Vishal Upendran , Durgesh Tripathi

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

Spectroscopic observations at extreme and far ultraviolet wavelengths have revealed systematic upflows in the solar transition region and corona. These upflows are best seen in the network structures of the quiet Sun and coronal holes,…

Solar and Stellar Astrophysics · Physics 2021-03-17 Hui Tian , Louise Harra , Deborah Baker , David H. Brooks , Lidong Xia

Two of the most important features of the solar atmosphere are its hot, smooth coronal loops and the concentrations of magnetic shear, known as filament channels, that reside above photospheric polarity inversion lines (PILs). The shear…

Solar and Stellar Astrophysics · Physics 2016-06-30 Kalman J. Knizhnik

We report on the merging between the southern polar coronal hole and an adjacent coronal dimming induced by a coronal mass ejection on 2022 March 18, resulting in the merged region persisting for at least 72 hrs. We use remote sensing data…

Solar and Stellar Astrophysics · Physics 2023-06-28 Nawin Ngampoopun , David M. Long , Deborah Baker , Lucie M. Green , Stephanie L. Yardley , Alexander W. James , Andy S. H. To

Recent advances have made it possible to obtain two-dimensional line-of-sight magnetic field maps of the solar corona from spectropolarimetric observations of the Fe XIII 1075 nm forbidden coronal emission line. Together with the linear…

Astrophysics · Physics 2009-11-13 Yu Liu , Haosheng Lin

We present a rare observation of direct magnetic interaction between an activating filament and a coronal hole (CH). The filament was a quiescent one located at the northwest of the CH. It underwent a nonradial activation, during which…

Solar and Stellar Astrophysics · Physics 2014-04-30 Ma Lin , Qu Zhong-Quan , Yan Xiao-Li , Xue Zhi-Ke

The origin and evolution of the magnetic helicity in the solar corona are not well understood. For instance, the magnetic helicity of an active region is often about $10^{42}$ Mx$^2$ ($10^{26}$ Wb$^{2}$), but the observed processes whereby…

Solar and Stellar Astrophysics · Physics 2009-11-13 S. Regnier

Solar atmosphere is a single system unified by the presence of large-scale magnetic fields. Topological changes in magnetic fields that occur in one place may have consequences for coronal heating and eruptions for other, even remote…

Solar and Stellar Astrophysics · Physics 2013-02-05 Alexei A. Pevtsov

Coronal plumes are narrow, collimated structures that are primarily viewed above the solar poles and in coronal holes in the extreme ultraviolet, but also in sunspots. Open questions remain about plume formation, including the role of…

Solar and Stellar Astrophysics · Physics 2025-07-24 Ayla Weitz , Sanjiv K. Tiwari , Gianna Cauzzi , Kevin P. Reardon , Bart De Pontieu

Coronal jets are short-lived eruptive features commonly observed in polar coronal holes and are thought to play a key role in the transfer of mass and energy into the solar corona. We describe unique contemporaneous observations of a…

Poynting flux generated by random shuffling of photospheric magnetic footpoints is transferred through the upper atmosphere of the Sun where the plasma is heated to over 1 MK in the corona. High spatiotemporal resolution observations of the…

Solar and Stellar Astrophysics · Physics 2024-11-20 L. P. Chitta , M. van Noort , H. N. Smitha , E. R. Priest , L. H. M. Rouppe van der Voort

Magnetic loops filled with hot plasma are the main building blocks of the solar corona. Usually they have lengths of the order of the barometric scale height in the corona that is 50 Mm. Previously it has been suggested that miniature…

Solar and Stellar Astrophysics · Physics 2017-03-15 Krzysztof Barczynski , Hardi Peter , Sabrina L. Savage

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

Arch-like loop structures filled with million Kelvin hot plasma form the building blocks of the quiet-Sun corona. Both high-resolution observations and magnetoconvection simulations show the ubiquitous presence of magnetic fields on the…

Magnetism defines the complex and dynamic solar corona. Twists and tangles in coronal magnetic fields build up energy and ultimately erupt, hurling plasma into interplanetary space. These coronal mass ejections (CMEs) are transient riders…

Solar and Stellar Astrophysics · Physics 2017-11-28 Sarah Gibson