Show simple item record

Files in this item


Item metadata

dc.contributor.authorIsliker, H.
dc.contributor.authorArchontis, V.
dc.contributor.authorVlahos, L.
dc.identifier.citationIsliker , H , Archontis , V & Vlahos , L 2019 , ' Particle acceleration and heating in regions of magnetic flux emergence ' , Astrophysical Journal , vol. 882 , no. 1 , 57 .
dc.identifier.otherPURE: 261267065
dc.identifier.otherPURE UUID: 2684e3b1-fa27-4dc1-a1b2-d2c53106cbd5
dc.identifier.otherBibtex: urn:7ae6e3fff638ed313d7f05bd3668b80c
dc.identifier.otherScopus: 85072348404
dc.identifier.otherORCID: /0000-0002-6926-8676/work/73700875
dc.identifier.otherWOS: 000484164800008
dc.descriptionL.V. was partly supported by the European Union (European Social Fund) and the Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Frame Work Research Funding Program: Thales. Investing in Knowledge Society through the European Social Fund. V.A. acknowledges support by the Royal Society.en
dc.description.abstractThe interaction between emerging and pre-existing magnetic fields in the solar atmosphere can trigger several dynamic phenomena, such as eruptions and jets. A key element during this interaction is the formation of large-scale current sheets, and eventually their fragmentation that leads to the creation of a strongly turbulent environment. In this paper, we study the kinetic aspects of the interaction (reconnection) between emerging and ambient magnetic fields. We show that the statistical properties of the spontaneously fragmented and fractal electric fields are responsible for the efficient heating and acceleration of charged particles, which form a power-law tail at high energies on sub-second timescales. A fraction of the energized particles escapes from the acceleration volume, with a super-hot component with a temperature close to 150 MK, and with a power-law high-energy tail with an index between −2 and −3. We estimate the transport coefficients in energy space from the dynamics of the charged particles inside the fragmented and fractal electric fields, and the solution of a fractional transport equation, as appropriate for a strongly turbulent plasma, agrees with the test-particle simulations. We also show that the acceleration mechanism is not related to Fermi acceleration, and the Fokker–Planck equation is inconsistent and not adequate as a transport model. Finally, we address the problem of correlations between spatial transport and transport in energy space. Our results confirm the observations reported for high-energy particles (hard X-rays, type III bursts, and solar energetic particles) during the emission of solar jets.
dc.relation.ispartofAstrophysical Journalen
dc.rightsCopyright © 2019. The American Astronomical Society. All rights reserved. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the final published version of the work, which was originally published at
dc.subjectMagnetic reconnectionen
dc.subjectMagnetohydrodynamics (MHD)en
dc.subjectSolar energetic particlesen
dc.subjectSolar magnetic fluxen
dc.subjectQB Astronomyen
dc.titleParticle acceleration and heating in regions of magnetic flux emergenceen
dc.typeJournal articleen
dc.contributor.sponsorThe Royal Societyen
dc.description.versionPublisher PDFen
dc.contributor.institutionUniversity of St Andrews. Applied Mathematicsen
dc.description.statusPeer revieweden

This item appears in the following Collection(s)

Show simple item record