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dc.contributor.authorTeed, Roberten
dc.contributor.authorProctor, Michaelen
dc.date.accessioned2017-05-04T15:37:00Z
dc.date.available2017-05-04T15:37:00Z
dc.date.issued2017-02-17en
dc.identifier.issn0035-8711
dc.identifier.urihttps://www.repository.cam.ac.uk/handle/1810/264038
dc.description.abstractThe solar magnetic field displays features on a wide range of length-scales including spatial and temporal coherence on scales considerably larger than the chaotic convection that generates the field. Explaining how the Sun generates and sustains such large-scale magnetic field has been a major challenge of dynamo theory for many decades. Traditionally, the ‘mean-field’ approach, utilizing the well-known α-effect, has been used to explain the generation of large-scale field from small-scale turbulence. However, with the advent of increasingly high-resolution computer simulations there is doubt as to whether the mean-field method is applicable under solar conditions. Models such as the ‘shear dynamo’ provide an alternative mechanism for the generation of large-scale field. In recent work, we showed that while coherent magnetic field was possible under kinematic conditions (where the kinetic energy is far greater than magnetic energy), the saturated state typically displayed a destruction of large-scale field and a transition to a small-scale state. In this paper, we report that the quenching of large-scale field in this way is not the only regime possible in the saturated state of this model. Across a range of simulations, we find a quasi-cyclic behaviour where a large-scale field is preserved and oscillates between two preferred length-scales. In this regime, the kinetic and magnetic energies can be of a similar order of magnitude. These results demonstrate that there is mileage in the shear dynamo as a model for the solar dynamo.
dc.description.sponsorshipThis work was supported by the Science and Technology Facilities Council, grant ST/L000636/1.
dc.language.isoenen
dc.publisherOxford University Press
dc.subjectdynamoen
dc.subjectmagnetic fieldsen
dc.subjectMHDen
dc.subjectmethods: numericalen
dc.titleQuasi-cyclic behaviour in non-linear simulations of the shear dynamoen
dc.typeArticle
prism.endingPage4864
prism.issueIdentifier4en
prism.publicationDate2017en
prism.publicationNameMonthly Notices of the Royal Astronomical Societyen
prism.startingPage4858
prism.volume467en
dc.identifier.doi10.17863/CAM.9399
dcterms.dateAccepted2017-02-15en
rioxxterms.versionofrecord10.1093/mnras/stx421en
rioxxterms.versionVoRen
rioxxterms.licenseref.urihttp://www.rioxx.net/licenses/all-rights-reserveden
rioxxterms.licenseref.startdate2017-02-17en
dc.contributor.orcidProctor, Michael [0000-0002-2249-342X]
dc.identifier.eissn1365-2966
rioxxterms.typeJournal Article/Reviewen
pubs.funder-project-idSTFC (ST/L000636/1)
pubs.funder-project-idSTFC (ST/P000673/1)


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