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Related papers: Long-lived coronal loops in solar active regions

200 papers

The ubiquity of recently discovered low-amplitude decayless kink oscillations of plasma loops allows for the seismological probing of the corona on a regular basis. In particular, in contrast to traditionally applied seismology which is…

Solar and Stellar Astrophysics · Physics 2019-11-06 Sergey A. Anfinogentov , Valery. M. Nakariakov

The 1998 April 20 spectral line data from the Coronal Diagnostics Spectrometer (CDS) on the {\it Solar and Heliospheric Observatory} (\SOHO) shows a coronal loop on the solar limb. Our original analysis of these data showed that the plasma…

Astrophysics · Physics 2009-11-11 J. T. Schmelz , K. Nasraoui , V. L. Richardson , P. J. Hubbard , C. R. Nevels , J. E. Beene

The quiet solar corona consists of myriads of loop-like features, with magnetic fields originating from network and internetwork regions on the solar surface. The continuous interaction between these different magnetic patches leads to…

Solar and Stellar Astrophysics · Physics 2021-04-13 L. P. Chitta , H. Peter , P. R. Young

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

Coronal loops exist ubiquitously in the solar atmosphere. These loops puzzle astronomers over half a century. Solar magneto-seismology (SMS) provides a unique way to constrain the physical parameters of coronal loops. Here, we study the…

Solar and Stellar Astrophysics · Physics 2018-03-20 W. Su , Y. Guo , R. Erdélyi , Z. J. Ning , M. D. Ding , X. Cheng , B. L. Tan

Aims: Emission line profiles from solar coronal loops exhibit properties that are unexplained by current models. We investigate the non-thermal broadening associated with plasma heating in coronal loops that is induced by magnetic field…

Solar and Stellar Astrophysics · Physics 2020-08-28 D. I. Pontin , H. Peter , L. P. Chitta

In solar coronal loops, thermal non-equilibrium (TNE) is a phenomenon that can occur when the heating is both highly-stratified and quasi-constant. Unambiguous observational identification of TNE would thus permit to strongly constrain…

Solar and Stellar Astrophysics · Physics 2017-02-08 Clara Froment , Frédéric Auchère , Guillaume Aulanier , Zoran Mikić , Karine Bocchialini , Eric Buchlin , Jacques Solomon

The structure of the solar corona is dominated by the magnetic field because the magnetic pressure is about four orders of magnitude higher than the plasma pressure. Due to the high conductivity the emitting coronal plasma (visible e.g. in…

Astrophysics · Physics 2009-06-25 T. Wiegelmann , B. Inhester , A. Lagg , S. K. Solanki

Context. Recent observations by the Extreme Ultraviolet Imager (EUI) on board Solar Orbiter have characterized prevalent small-scale transient brightenings in the corona above the quiet Sun termed campfires. Aims. In this study we search…

Solar and Stellar Astrophysics · Physics 2021-12-15 Yajie Chen , Damien Przybylski , Hardi Peter , Hui Tian , F. Auchère , D. Berghmans

Oscillations are abundant in the solar corona. Coronal loop oscillations are typically studied using highly idealised models of magnetic flux tubes. In order to improve our understanding of coronal oscillations, it is necessary to consider…

Solar and Stellar Astrophysics · Physics 2023-08-02 P. Kohutova , P. Antolin , M. Szydlarski , M. Carlsson

We study a series of relations between physical parameters in coronal loops of the quiet Sun reconstructed by combining tomographic techniques and modeling of the coronal magnetic field. We use differential emission measure tomography…

Solar and Stellar Astrophysics · Physics 2022-06-22 C. Mac Cormack , M. López Fuentes , C. H. Mandrini , D. G. Lloveras , M. Poisson , A. M. Vásquez

In this paper we further develop a model for the heating of coronal loops by Alfven wave turbulence (AWT). The Alfven waves are assumed to be launched from a collection of kilogauss flux tubes in the photosphere at the two ends of the loop.…

Solar and Stellar Astrophysics · Physics 2017-11-08 Adriaan A. van Ballegooijen , Mahboubeh Asgari-Targhi , Alexander Voss

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

Within the quiet Sun corona imaged at 1 MK, much of the field of view consists of diffuse emission that appears to lack the spatial structuring that is so evident in coronal loops or bright points. We seek to determine if these diffuse…

It is largely agreed that many coronal loops---those observed at a temperature of about 1 MK--- are bundles of unresolved strands that are heated by storms of impulsive nanoflares. The nature of coronal heating in hotter loops and in the…

Solar and Stellar Astrophysics · Physics 2015-05-28 Nicholeen M. Viall , James A. Klimchuk

Context: Long-period intensity pulsations were recently detected in the EUV emission of coronal loops, and have been attributed to cycles of plasma evaporation and condensation driven by thermal non-equilibrium (TNE). Numerical simulations…

Solar and Stellar Astrophysics · Physics 2020-02-12 Gabriel Pelouze , Frédéric Auchère , Karine Bocchialini , Clara Froment , Susanna Parenti , Elie Soubrié

Coronal fan loops rooted in sunspot umbra show outward propagating waves with subsonic phase speed and period around 3-min. However, their source region in the lower atmosphere is still ambiguous. We performed multi-wavelength observations…

Solar and Stellar Astrophysics · Physics 2023-09-06 Ananya Rawat , Girjesh Gupta

We report on the discovery of periodic coronal rain in an off-limb sequence of {\it Solar Dynamics Observatory}/Atmospheric Imaging Assembly images. The showers are co-spatial and in phase with periodic (6.6~hr) intensity pulsations of…

Solar and Stellar Astrophysics · Physics 2018-02-21 F. Auchère , C. froment , E. Soubrié , P. Antolin , R. Oliver , G. Pelouze

We investigate a possibility of heating of the loops and other closed magnetic structures in active regions of the solar corona by the flow of solar wind (plus other flows that may be present) across the magnetic field lines (that are…

Astrophysics · Physics 2007-05-23 David Tsiklauri

We have expanded upon earlier work that investigates the relative importance of coronal loops with isothermal $versus$ multithermal cross-field temperature distributions. These results are important for determining if loops have…

Solar and Stellar Astrophysics · Physics 2017-05-29 J. T. Schmelz , G. M. Christian , R. A. Chastain