Heating Effects from Driven Transverse and Alfvén Waves in Coronal Loops
| Autor: | Tom Van Doorsselaere, Ineke De Moortel, Mingzhe Guo, Bo Li, Patrick Antolin, Konstantinos Karampelas |
|---|---|
| Přispěvatelé: | European Research Council, Science & Technology Facilities Council, University of St Andrews. Applied Mathematics |
| Rok vydání: | 2019 |
| Předmět: |
corona [Sun]
010504 meteorology & atmospheric sciences F300 T-NDAS PROPAGATION F500 Astronomy & Astrophysics magnetohydrodynamics (MHD) 01 natural sciences Instability 0103 physical sciences QB Astronomy RESONANT ABSORPTION TRANSITION-REGION Astrophysics::Solar and Stellar Astrophysics waves 010303 astronomy & astrophysics QC QB 0105 earth and related environmental sciences Physics Science & Technology Internal energy Turbulence SEISMOLOGY MAGNETIC-FIELD Astronomy and Astrophysics Observable Plasma Mechanics Coronal loop Dissipation SOLAR CHROMOSPHERE KINK OSCILLATIONS Transverse plane QC Physics magnetic fields [Sun] MHD WAVES Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science Physical Sciences Physics::Space Physics MODES MAGNETOHYDRODYNAMIC WAVES |
| Zdroj: | The Astrophysical Journal |
| ISSN: | 1538-4357 0004-637X 0004-6361 0067-0049 |
| DOI: | 10.3847/1538-4357/aaf1d0 |
| Popis: | Funding: This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No.724326 and No.647214) (IDM). P.A. acknowledges funding from his STFC Ernest Rutherford Fellowship (No. ST/R004285/1). Recent numerical studies revealed that transverse motions of coronal loops can induce the Kelvin-Helmholtz Instability (KHI). This process could be important in coronal heating because it leads to dissipation of energy at small spatial-scale plasma interactions. Meanwhile, small amplitude decayless oscillations in coronal loops have been discovered recently in observations of SDO/AIA. We model such oscillations in coronal loops and study wave heating effects, considering a kink and Alfvén driver separately and a mixed driver at the bottom of flux tubes. Both the transverse and Alfvén oscillations can lead to the KHI. Meanwhile, the Alfvén oscillations established in loops will experience phase mixing. Both processes will generate small spatial-scale structures, which can help the dissipation of wave energy. Indeed, we observe the increase of internal energy and temperature in loop regions. The heating is more pronounced for the simulation containing the mixed kink and Alfvén driver. This means that the mixed wavemodes can lead to a more efficient energy dissipation in the turbulent state of the plasma and that the KHI eddies act as an agent to dissipate energy in other wave modes. Furthermore, we also obtained forward modelling results using the FoMo code. We obtained forward models which are very similar to the observations of decayless oscillations. Due to the limited resolution of instruments, neither Alfvén modes nor the fine structures are observable. Therefore, this numerical study shows that Alfvén modes probably can co-exist with kink modes, leading to enhanced heating. Postprint |
| Databáze: | OpenAIRE |
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