Theory of multidimensional electron-scale instabilities in unmagnetized shear flows
Autor(a) principal: | |
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Data de Publicação: | 2013 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://iopscience.iop.org/0741-3335/55/12/124031/ https://ciencia.iscte-iul.pt/public/pub/id/13326 http://hdl.handle.net/10071/7298 |
Resumo: | Collisionless plasma instabilities operating on the electron time scale can be of importance to explain magnetic field generation; however, their role has been addressed in scenarios where velocity shear is absent. We show that, whenever present, velocity shears must be considered in the electron time scale since electromagnetic perturbations are unstable, both in the parallel (two fluids Kelvin-Helmholtz instability) and in the transverse plane of the flow. Using the two-fluid formalism in the limit of cold plasma, we derive the dispersion relations of the instability in the parallel plane. As the instabilities grow, we also show, through a kinetic model, the development of a dc magnetic field, extending all over the shear region, that reaches a typical value at a saturation of eB(dc)(sat)/mc omega(p) similar to beta(0)root gamma(0), where beta(0) and gamma(0) are respectively the normalized velocity and the Lorentz factor of the plasma flow. |
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Theory of multidimensional electron-scale instabilities in unmagnetized shear flowsCollisionless plasma instabilities operating on the electron time scale can be of importance to explain magnetic field generation; however, their role has been addressed in scenarios where velocity shear is absent. We show that, whenever present, velocity shears must be considered in the electron time scale since electromagnetic perturbations are unstable, both in the parallel (two fluids Kelvin-Helmholtz instability) and in the transverse plane of the flow. Using the two-fluid formalism in the limit of cold plasma, we derive the dispersion relations of the instability in the parallel plane. As the instabilities grow, we also show, through a kinetic model, the development of a dc magnetic field, extending all over the shear region, that reaches a typical value at a saturation of eB(dc)(sat)/mc omega(p) similar to beta(0)root gamma(0), where beta(0) and gamma(0) are respectively the normalized velocity and the Lorentz factor of the plasma flow.IOP Publishing Ltd2014-05-21T10:55:34Z2013-12-01T00:00:00Z2013-122014-05-21T10:44:04Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://iopscience.iop.org/0741-3335/55/12/124031/https://ciencia.iscte-iul.pt/public/pub/id/13326http://hdl.handle.net/10071/7298eng0741-3335Grismayer, T.Alves, E. P.Fonseca, R. A.Silva, L. O.info:eu-repo/semantics/embargoedAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-11-09T17:39:43Zoai:repositorio.iscte-iul.pt:10071/7298Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T22:18:18.040192Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Theory of multidimensional electron-scale instabilities in unmagnetized shear flows |
title |
Theory of multidimensional electron-scale instabilities in unmagnetized shear flows |
spellingShingle |
Theory of multidimensional electron-scale instabilities in unmagnetized shear flows Grismayer, T. |
title_short |
Theory of multidimensional electron-scale instabilities in unmagnetized shear flows |
title_full |
Theory of multidimensional electron-scale instabilities in unmagnetized shear flows |
title_fullStr |
Theory of multidimensional electron-scale instabilities in unmagnetized shear flows |
title_full_unstemmed |
Theory of multidimensional electron-scale instabilities in unmagnetized shear flows |
title_sort |
Theory of multidimensional electron-scale instabilities in unmagnetized shear flows |
author |
Grismayer, T. |
author_facet |
Grismayer, T. Alves, E. P. Fonseca, R. A. Silva, L. O. |
author_role |
author |
author2 |
Alves, E. P. Fonseca, R. A. Silva, L. O. |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Grismayer, T. Alves, E. P. Fonseca, R. A. Silva, L. O. |
description |
Collisionless plasma instabilities operating on the electron time scale can be of importance to explain magnetic field generation; however, their role has been addressed in scenarios where velocity shear is absent. We show that, whenever present, velocity shears must be considered in the electron time scale since electromagnetic perturbations are unstable, both in the parallel (two fluids Kelvin-Helmholtz instability) and in the transverse plane of the flow. Using the two-fluid formalism in the limit of cold plasma, we derive the dispersion relations of the instability in the parallel plane. As the instabilities grow, we also show, through a kinetic model, the development of a dc magnetic field, extending all over the shear region, that reaches a typical value at a saturation of eB(dc)(sat)/mc omega(p) similar to beta(0)root gamma(0), where beta(0) and gamma(0) are respectively the normalized velocity and the Lorentz factor of the plasma flow. |
publishDate |
2013 |
dc.date.none.fl_str_mv |
2013-12-01T00:00:00Z 2013-12 2014-05-21T10:55:34Z 2014-05-21T10:44:04Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://iopscience.iop.org/0741-3335/55/12/124031/ https://ciencia.iscte-iul.pt/public/pub/id/13326 http://hdl.handle.net/10071/7298 |
url |
http://iopscience.iop.org/0741-3335/55/12/124031/ https://ciencia.iscte-iul.pt/public/pub/id/13326 http://hdl.handle.net/10071/7298 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
0741-3335 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/embargoedAccess |
eu_rights_str_mv |
embargoedAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
IOP Publishing Ltd |
publisher.none.fl_str_mv |
IOP Publishing Ltd |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
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1799134742253142016 |