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dc.contributor.authorYeates, A. R.
dc.contributor.authorConstable, J. A.
dc.contributor.authorMartens, P. C. H.
dc.identifier.citationYeates , A R , Constable , J A & Martens , P C H 2010 , ' Solar cycle variation of magnetic flux ropes in a quasi-static coronal evolution model ' , Solar Physics , vol. 263 , no. 1 , pp. 121-134 .
dc.identifier.otherPURE: 243585732
dc.identifier.otherPURE UUID: e6a0abc3-6e02-4959-9edc-ff38fd5f170f
dc.identifier.otherScopus: 77951975057
dc.description.abstractThe structure of electric current and magnetic helicity in the solar corona is closely linked to solar activity over the 11-year cycle, yet is poorly understood. As an alternative to traditional current-free "potential field" extrapolations, we investigate a model for the global coronal magnetic field which is non-potential and time-dependent, following the build-up and transport of magnetic helicity due to flux emergence and large-scale photospheric motions. This helicity concentrates into twisted magnetic flux ropes, which may lose equilibrium and be ejected. Here, we consider how the magnetic structure predicted by this model-in particular the flux ropes-varies over the solar activity cycle, based on photospheric input data from six periods of cycle 23. The number of flux ropes doubles from minimum to maximum, following the total length of photospheric polarity inversion lines. However, the number of flux rope ejections increases by a factor of eight, following the emergence rate of active regions. This is broadly consistent with the observed cycle modulation of coronal mass ejections, although the actual rate of ejections in the simulation is about a fifth of the rate of observed events. The model predicts that, even at minimum, differential rotation will produce sheared, non-potential, magnetic structure at all latitudes.
dc.relation.ispartofSolar Physicsen
dc.rights© 2010, Springer. 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.subjectCoronal mass ejections, theoryen
dc.subjectMagnetic fields, coronaen
dc.subjectMagnetic fields, modelsen
dc.subjectSolar cycle, modelsen
dc.subjectQB Astronomyen
dc.subjectQC Physicsen
dc.titleSolar cycle variation of magnetic flux ropes in a quasi-static coronal evolution modelen
dc.typeJournal articleen
dc.contributor.institutionUniversity of St Andrews.Applied Mathematicsen
dc.description.statusPeer revieweden

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