Detalhes bibliográficos
Título da fonte: Repositório Institucional da UFMG
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oai_identifier_str oai:repositorio.ufmg.br:1843/60871
network_acronym_str UFMG
network_name_str Repositório Institucional da UFMG
repository_id_str
reponame_str Repositório Institucional da UFMG
instacron_str UFMG
institution Universidade Federal de Minas Gerais (UFMG)
instname_str Universidade Federal de Minas Gerais (UFMG)
spelling 2023-11-13T16:34:45Z2023-11-13T16:34:45Z2021503112901309https://doi.org/10.1093/mnras/stab4701365-2966http://hdl.handle.net/1843/60871https://orcid.org/0000-0001-6880-4468https://orcid.org/0000-0002-2671-8796https://orcid.org/0000-0001-8058-4752https://orcid.org/0000-0002-7336-6674CNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPESP - Fundação de Amparo à Pesquisa do Estado de São PauloThe rate of magnetic field diffusion plays an essential role in several astrophysical plasma processes. It has been demonstrated that the omnipresent turbulence in astrophysical media induces fast magnetic reconnection, which consequently leads to large-scale magnetic flux diffusion at a rate independent of the plasma microphysics. This process is called 'reconnection diffusion' (RD) and allows for the diffusion of fields, which are dynamically important. The current theory describing RD is based on incompressible magnetohydrodynamic (MHD) turbulence. In this work, we have tested quantitatively the predictions of the RD theory when magnetic forces are dominant in the turbulence dynamics (Alfvénic Mach number MA < 1). We employed the Pencil Code to perform numerical simulations of forced MHD turbulence, extracting the values of the diffusion coefficient ηRD using the test-field method. Our results are consistent with the RD theory (⁠ηRD∼M3A for MA < 1) when turbulence approaches the incompressible limit (sonic Mach number MS ≲ 0.02), while for larger MS the diffusion is faster (⁠ηRD∼M2A⁠). This work shows for the first time simulations of compressible MHD turbulence with the suppression of the cascade in the direction parallel to the mean magnetic field, which is consistent with incompressible weak turbulence theory. We also verified that in our simulations the energy cascading time does not follow the scaling with MA predicted for the weak regime, in contradiction with the RD theory assumption. Our results generally support and expand the RD theory predictions.engUniversidade Federal de Minas GeraisUFMGBrasilICX - DEPARTAMENTO DE FÍSICAMonthly Notices of the Royal Astronomical SocietyCampos magnéticosEstrelasDifusãoMagnetic fieldsMagnetic reconnectionMagnetohydrodynamicTurbulenceStarsDiffusion of large-scale magnetic fields by reconnection in MHD turbulenceinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttps://academic.oup.com/mnras/article/503/1/1290/6144594Reinaldo Santos de LimaGustavo Andres Guerrero ErasoElisabete Maria de Gouveia Dal PinoAlex Lazarianapplication/pdfinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFMGinstname:Universidade Federal de Minas Gerais (UFMG)instacron:UFMGLICENSELicense.txtLicense.txttext/plain; charset=utf-82042https://repositorio.ufmg.br/bitstream/1843/60871/1/License.txtfa505098d172de0bc8864fc1287ffe22MD51ORIGINALDiffusion of large-scale magnetic fields by reconnection in MHD.pdfDiffusion of large-scale magnetic fields by reconnection in MHD.pdfapplication/pdf5640748https://repositorio.ufmg.br/bitstream/1843/60871/2/Diffusion%20of%20large-scale%20magnetic%20fields%20by%20reconnection%20in%20MHD.pdff6f80ee7d0075c6eb6ce1576d9868754MD521843/608712023-11-13 18:44:18.575oai:repositorio.ufmg.br:1843/60871Repositório InstitucionalPUBhttps://repositorio.ufmg.br/oaiopendoar:2023-11-13T21:44:18Repositório Institucional da UFMG - Universidade Federal de Minas Gerais (UFMG)false
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