Show simple item record

Files in this item


Item metadata

dc.contributor.authorDe Moortel, Ineke
dc.contributor.authorPascoe, David James
dc.contributor.authorWright, Andrew Nicholas
dc.contributor.authorHood, Alan William
dc.identifier.citationDe Moortel , I , Pascoe , D J , Wright , A N & Hood , A W 2016 , ' Transverse, propagating velocity perturbations in solar coronal loops ' , Plasma Physics and Controlled Fusion , vol. 58 , no. 1 , 014001 .
dc.identifier.otherPURE: 221467700
dc.identifier.otherPURE UUID: 2c647e2b-d221-4c89-b677-dc600fcf910a
dc.identifier.otherScopus: 84949658543
dc.identifier.otherWOS: 000368471900002
dc.description.abstractAs waves and oscillations carry both energy and information, they have enormous potential as a plasma heating mechanism and, through seismology, to provide estimates of local plasma properties which are hard to obtain from direct measurements. Being sufficiently near to allow high-resolution observations, the atmosphere of the Sun forms a natural plasma laboratory. Recent observations have revealed that an abundance of waves and oscillations is present in the solar atmosphere, leading to a renewed interest in wave heating mechanisms. This short review paper gives an overview of recently observed transverse, propagating velocity perturbations in coronal loops. These ubiquitous perturbations are observed to undergo strong damping as they propagate. Using 3D numerical simulations of footpoint-driven transverse waves propagating in a coronal plasma with a cylindrical density structure, in combination with analytical modelling, it is demonstrated that the observed velocity perturbations can be understood in terms of coupling of different wave modes in the inhomogeneous boundaries of the loops. Mode coupling in the inhomogeneous boundary layers of the loops leads to the coupling of the transversal (kink) mode to the azimuthal (Alfven) mode, observed as the decay of the transverse kink oscillations. Both the numerical and analytical results show the spatial profile of the damped wave has a Gaussian shape to begin with, before switching to exponential decay at large heights. In addition, recent analysis of CoMP (Coronal Multi-channel Polarimeter) Doppler shift observations of large, off-limb, trans-equatorial loops shows that Fourier power at the apex appears to be higher in the high-frequency part of the spectrum than expected from theoretical models. This excess high-frequency FFT power could be tentative evidence for the onset of a cascade of the low-to-mid frequency waves into (Alfvenic) turbulence.
dc.relation.ispartofPlasma Physics and Controlled Fusionen
dc.rights© 2015, Publisher / the Author(s). This work is made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at /
dc.subjectMHD wavesen
dc.subjectQB Astronomyen
dc.subjectQA Mathematicsen
dc.subjectQC Physicsen
dc.titleTransverse, propagating velocity perturbations in solar coronal loopsen
dc.typeJournal itemen
dc.contributor.institutionUniversity of St Andrews.Applied Mathematicsen
dc.contributor.institutionUniversity of St Andrews.School of Mathematics and Statisticsen
dc.description.statusPeer revieweden

This item appears in the following Collection(s)

Show simple item record