Loss-cone instability modulation due to a magnetohydrodynamic sausage mode oscillation in the solar corona

Autor: Laura A. Hayes, Warren Shelley, Peter T. Gallagher, Eoin P. Carley, Diana E. Morosan, Nicole Vilmer, Sophie A. Murray
Přispěvatelé: Trinity College Dublin, Dublin Institute for Advanced Studies (DIAS), NASA Goddard Space Flight Center (GSFC), University of Helsinki, Boston University [Boston] (BU), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), French Program on Solar-Terrestrial Physics of INSU (PNST, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Space Physics Research Group, Particle Physics and Astrophysics, Department of Physics
Jazyk: angličtina
Rok vydání: 2019
Předmět:
0301 basic medicine
Astrophysical plasmas
Science
Astrophysics::High Energy Astrophysical Phenomena
General Physics and Astronomy
02 engineering and technology
Instability
114 Physical sciences
Magnetically confined plasmas
Article
General Biochemistry
Genetics and Molecular Biology
03 medical and health sciences
CYCLOTRON MASER INSTABILITY
RADIO PULSATIONS
Physics::Plasma Physics
ABSORPTION
BURSTS
TRANSITION-REGION
Astrophysics::Solar and Stellar Astrophysics
PLASMA RADIATION
Magnetohydrodynamic drive
lcsh:Science
Computer Science::Databases
Physics
Solar physics
Multidisciplinary
Solar flare
Oscillation
[SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR]
SIGNATURE
Magnetic reconnection
General Chemistry
Plasma
021001 nanoscience & nanotechnology
115 Astronomy
Space science
Computational physics
ELECTRONS
030104 developmental biology
13. Climate action
Physics::Space Physics
lcsh:Q
Magnetohydrodynamics
INJECTION
0210 nano-technology
EMISSION
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Zdroj: Nature Communications, Vol 10, Iss 1, Pp 1-12 (2019)
Nature Communications
Nature Communications, Nature Publishing Group, 2019, 10, ⟨10.1038/s41467-019-10204-1⟩
ISSN: 2041-1723
DOI: 10.1038/s41467-019-10204-1
Popis: Solar flares often involve the acceleration of particles to relativistic energies and the generation of high-intensity bursts of radio emission. In some cases, the radio bursts can show periodic or quasiperiodic intensity pulsations. However, precisely how these pulsations are generated is still subject to debate. Prominent theories employ mechanisms such as periodic magnetic reconnection, magnetohydrodynamic (MHD) oscillations, or some combination of both. Here we report on high-cadence (0.25 s) radio imaging of a 228 MHz radio source pulsating with a period of 2.3 s during a solar flare on 2014-April-18. The pulsating source is due to an MHD sausage mode oscillation periodically triggering electron acceleration in the corona. The periodic electron acceleration results in the modulation of a loss-cone instability, ultimately resulting in pulsating plasma emission. The results show that a complex combination of MHD oscillations and plasma instability modulation can lead to pulsating radio emission in astrophysical environments.
Magnetohydrodynamic (MHD) waves and plasma instabilities can be studied during solar flares. Here the authors show evidence for an MHD sausage mode oscillation periodically triggering electron acceleration at a magnetic null point in the solar corona, indicating MHD oscillations in plasma can indirectly lead to loss-cone instability modulation.
Databáze: OpenAIRE
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