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Related papers: Miniature loops in the solar corona

200 papers

The solar corona has been revealed in the past decade to be a highly dynamic nonequilibrium plasma environment. Both the loop-filled coronal base and the extended acceleration region of the solar wind appear to be strongly turbulent, but…

Astrophysics · Physics 2008-11-26 Steven R. Cranmer

Spicules have been proposed as significant contributors to the mass and energy balance of the corona. While previous observations have provided a glimpse of short-lived transient brightenings in the corona that are associated with spicules,…

Solar and Stellar Astrophysics · Physics 2017-10-19 Bart De Pontieu , Ineke De Moortel , Juan Martinez-Sykora , Scott McIntosh

The profiles of emission lines formed in the corona contain information on the dynamics and the heating of the hot plasma. Only recently has data with sufficiently high spectral resolution become available for investigating the details of…

Solar and Stellar Astrophysics · Physics 2015-05-18 H. Peter

The plasma-$\beta$ is an important fundamental physical quantity in solar plasma physics, which determines the dominating process in the solar atmosphere, i.e., magnetic or thermodynamic processes. Here, for the first time, we provide…

Solar and Stellar Astrophysics · Physics 2025-07-23 Ananya Rawat , Girjesh Gupta , Tom Van Doorsselaere , S. Krishna Prasad , Robertus Erdélyi

Magnetic flux ropes are bundles of twisted magnetic field enveloping a central axis. They harbor free magnetic energy and can be progenitors of coronal mass ejections (CMEs), but identifying flux ropes on the Sun can be challenging. One of…

We investigate the fine structure of magnetic fields in the atmosphere of the quiet Sun. We use photospheric magnetic field measurements from {\sc Sunrise}/IMaX with unprecedented spatial resolution to extrapolate the photospheric magnetic…

A theory for the heating of coronal magnetic flux ropes is developed. The dissipated magnetic energy has two distinct contributions: (1) energy injected into the corona as a result of granule-scale, random footpoint motions, and (2) energy…

Astrophysics · Physics 2009-11-13 A. A. van Ballegooijen , S. R. Cranmer

We present a statistical analysis for the characteristics and radial evolution of linear magnetic holes (LMHs) in the solar wind from 0.166 to 0.82 AU using Parker Solar Probe observations of the first two orbits. It is found that the LMHs…

Space Physics · Physics 2021-02-17 L. Yu , S. Y. Huang , Z. G. Yuan , K. Jiang , Q. Y. Xiong , S. B. Xu , Y. Y. Wei , J. Zhang , Z. H. Zhang

A model interpreting variations of EUV brightness upward propagating in solar coronal loops as slow magnetoacoustic waves is developed. A loop is considered to have a non-zero plane inclination angle and offset of circular loop centre from…

Astrophysics · Physics 2009-11-07 D. Tsiklauri , V. M. Nakariakov

Coronal heating through the explosive release of magnetic energy remains an open problem in solar physics. Recent hydrodynamical models attempt an investigation by placing swarms of 'nanoflares' at random sites and times in modeled…

Solar and Stellar Astrophysics · Physics 2016-11-30 K. Moraitis , A. Toutountzi , H. Isliker , M. Georgoulis , L. Vlahos , G. Chintzoglou

In this paper, we study in detail the evolution of a mini-sigmiod originating in a cross-equatorial coronal hole, where the magnetic field is mostly open and seriously distinct from the closed background field above active-region sigmoids.…

Solar and Stellar Astrophysics · Physics 2019-12-24 Z. W. Huang , X. Cheng , Y. N. Su , T. Liu , M. D. Ding

We use full-disk, SOHO/EIT 195 $\AA$ calibrated images to measure latitudinal and day to day variations of area and average photon fluxes of the near equatorial coronal holes. In addition, energy emitted by the coronal holes with their…

Solar and Stellar Astrophysics · Physics 2022-04-12 K. M. Hiremath , Manjunath Hegde

We carry out a study of the global three-dimensional (3D) structure of the electron density and temperature of the quiescent inner solar corona ($r<1.25 R_\odot$) by means of tomographic reconstructions and magnetohydrodynamic simulations.…

Solar and Stellar Astrophysics · Physics 2020-06-17 D. G. Lloveras , A. M. Vásquez , F. A. Nuevo , C. Mac Cormack , N. Sachdeva , W. Manchester , B. Van der Holst , R. A. Frazin

Solar coronal loops show significant plasma motions during their formation and eruption stages. Dynamic cool coronal structures, on the other hand, are often observed to propagate along coronal loops. In this paper, we report on the…

Space Physics · Physics 2015-05-14 J. Zhang , L. P. Li

We investigate the thermal, kinematic and magnetic structure of small-scale heating events in an emerging flux region (EFR). We use high-resolution multi-line observations (including Ca II 8542~\AA, Ca II K, and Fe I 6301~\AA line pair) of…

Solar and Stellar Astrophysics · Physics 2023-09-14 Rahul Yadav , Maria D. Kazachenko , Andrey N. Afanasyev , Jaime de la Cruz Rodríguez , Jorrit Leenaarts

A wide variety of phenomena such as gentle but persistent brightening, dynamic slender features (~100 km), and compact (~1'') ultraviolet (UV) bursts are associated with the heating of the solar chromosphere. High spatio-temporal resolution…

Solar and Stellar Astrophysics · Physics 2018-10-03 H. N. Smitha , L. P. Chitta , T. Wiegelmann , S. K. Solanki

Context. The structure and heating of coronal loops are investigated since decades. Established scaling laws relate fundamental quantities like the loop apex temperature, pressure, length, and the coronal heating. Aims. We test such scaling…

Solar and Stellar Astrophysics · Physics 2017-09-19 Philippe-A. Bourdin , Sven Bingert , Hardi Peter

Low-lying loops have been discovered at the solar limb in transition region temperatures by the Interface Region Imaging Spectrograph (IRIS). They do not appear to reach coronal temperatures, and it has been suggested that they are the…

Solar and Stellar Astrophysics · Physics 2018-04-11 Tiago M. D. Pereira , Luc Rouppe van der Voort , Viggo H. Hansteen , Bart De Pontieu

In coronal loop modeling, it is commonly assumed that the loops are semi-circular with a uniform cross-sectional area. However, observed loops are rarely semi-circular, and extrapolations of the magnetic field show that the field strength…

Solar and Stellar Astrophysics · Physics 2022-07-20 Jeffrey W. Reep , Ignacio Ugarte-Urra , Harry P. Warren , Will T. Barnes

We report preliminary results from a series of numerical simulations of the reduced magnetohydrodynamic equations, used to describe the dynamics of magnetic loops in active regions of the solar corona. A stationary velocity field is applied…

Astrophysics · Physics 2009-10-31 Pablo Dmitruk , Daniel Gomez