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Related papers: Disentangling flows in the solar transition region

200 papers

We present a detailed analysis of a 3D MHD simulation of a subset of the magnetic flux in an active region. The simulation models the generation of nanoflares and response of the plasma to imposed photospheric motions. Our study focuses on…

Solar and Stellar Astrophysics · Physics 2025-09-26 Shanwlee Sow Mondal , Lars K. S. Daldorff , James A. Klimchuk , Craig D. Johnston

What physical mechanisms heat the outer solar or stellar atmosphere to million-Kelvin temperatures is a fundamental but long-standing open question. In particular, the solar corona in active region cores contains an even hotter component…

Solar and Stellar Astrophysics · Physics 2024-04-09 Zekun Lu , Feng Chen , M. D. Ding , Can Wang , Yu Dai , Xin Cheng

Context. Supra-arcade downflows (SADs) have been frequently observed during the gradual phase of solar flares near the limb. In coronal emission lines sensitive to flaring plasmas, they appear as tadpole-like dark voids against the diffuse…

Solar and Stellar Astrophysics · Physics 2017-10-18 Xin Chen , Rui Liu , Na Deng , Haimin Wang

The atmosphere of the Sun is highly structured and dynamic in nature. From the photosphere and chromosphere into the transition region and the corona plasma-$\beta$ changes from above to below one, i.e. while in the lower atmosphere the…

Astrophysics · Physics 2008-11-26 H. Peter

Long-time high-resolution simulations of the dynamics of a coronal loop in cartesian geometry are carried out, within the framework of reduced magnetohydrodynamics (RMHD), to understand coronal heating driven by motion of field lines…

Astrophysics · Physics 2008-11-26 A. F. Rappazzo , M. Velli , G. Einaudi , R. B. Dahlburg

EUV imaging observations from several space missions (SOHO/EIT, TRACE, and SDO/AIA) have revealed a presence of propagating intensity disturbances in solar coronal loops. These disturbances are typically interpreted as slow magnetoacoustic…

Solar and Stellar Astrophysics · Physics 2018-01-24 Elena Provornikova , Leon Ofman , Tongjiang Wang

We conducted a high-resolution numerical simulation of the solar corona above a stable active region. The aim is to test the field-line braiding mechanism for a sufficient coronal energy input. We also check the applicability of scaling…

Solar and Stellar Astrophysics · Physics 2018-05-17 Philippe-A. Bourdin , Sven Bingert , Hardi Peter

The heating of the plasma in the solar atmosphere is discussed within both frameworks of fluid and kinetic drift wave theory. We show that the basic ingredient necessary for the heating is the presence of density gradients in the direction…

Solar and Stellar Astrophysics · Physics 2015-05-13 J. Vranjes , S. Poedts

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

Solar flares are explosive events in the solar corona, representing fast conversion of magnetic energy into thermal and kinetic energy, and hence radiation, due to magnetic reconnection. Modelling is essential for understanding and…

Solar and Stellar Astrophysics · Physics 2019-02-13 M. Gordovskyy , P. K. Browning , R. F. Pinto

Solar wind models predict that the mass flux carried away from the Sun in the solar wind should be extremely sensitive to the temperature in the corona, where the solar wind is accelerated. We perform a direct test of this prediction in…

Solar and Stellar Astrophysics · Physics 2021-06-02 D. Stansby , L. Berčič , L. Matteini , C. J. Owen , R. French , D. Baker , S. T. Badman

Observations on 2011 August 9 of an X6.9-class flare in active region (AR) 11263 by the Atmospheric Imaging Assembly (AIA) on-board the Solar Dynamics Observatory (SDO), were followed by a rare detection of vertical kink oscillations in a…

Solar and Stellar Astrophysics · Physics 2015-10-14 Leon Ofman , Marzia Parisi , Abhishek K. Srivastava

The formation of the MFRs in the pre-flare stage, and how this leads to coronal rain in a post-eruption magnetic loop is not fully understood. We explore the formation, and eruption of MFRs, followed by the appearance of coronal rain in the…

Solar and Stellar Astrophysics · Physics 2024-08-07 Samrat Sen , Avijeet Prasad , Valeriia Liakh , Rony Keppens

We study the propagation properties of slow magneto-acoustic waves in a multi-thermal coronal loop using a 3D MHD model, for the first time. A bundle of 33 vertical cylinders, each of 100{\,}km radius, randomly distributed over a circular…

Solar and Stellar Astrophysics · Physics 2024-06-06 S. Krishna Prasad , T. Van Doorsselaere

3D simulations of magnetic flux emergence are carried out in a computational domain spanning the upper layers of the convection zone to the lower corona. We use the Oslo Staggered Code to solve the full MHD equations with non-grey and NLTE…

Solar and Stellar Astrophysics · Physics 2009-08-11 J. Martinez-Sykora , V. Hansteen , M. Carlsson

Constraining the processes that drive coronal heating from observations is a difficult task due to the complexity of the solar atmosphere. As upcoming missions such as MUSE will provide coronal observations with unprecedented spatial and…

Solar and Stellar Astrophysics · Physics 2024-05-03 C. A. Breu , I. De Moortel , P. Testa

Solar variability investigations that include magnetic energy coupling are paramount to solving many key solar/stellar physics problems, particularly for understanding the temporal variability of magnetic energy redistribution and heating…

Solar and Stellar Astrophysics · Physics 2016-12-28 N. Brice Orange , David L. Chesny , Bruce Gendre , David C. Morris , Hakeem M. Oluseyi

This work addresses the effect of travelling thermal waves applied at the fluid layer surface, on the formation of global flow structures in 2D and 3D convective systems. For a broad range of Rayleigh numbers ($10^3\leq Ra \leq 10^7$) and…

Fluid Dynamics · Physics 2020-12-22 Philipp Reiter , Xuan Zhang , Rodion Stepanov , Olga Shishkina

The heating and structure of the solar chromosphere depends on the underlying magnetic field, among other parameters. The lowest magnetic flux of the solar atmosphere is found in the quiet Sun internetwork and is thought to be provided by…

Solar and Stellar Astrophysics · Physics 2025-11-19 D. Przybylski , R. Cameron , S. K. Solanki , M. Rempel , S. Danilovic , J. Leenaarts

Coronal rain, observed in 3D spine-fan magnetic configurations, results from thermal instability in the solar corona, where runaway in-situ cooling causes plasma to condense and drain along the magnetic lines. The reconnection of the…

Solar and Stellar Astrophysics · Physics 2025-06-18 Beatrice Popescu Braileanu , Rony Keppens