Magnetic Flux Transport Signatures of Electron-only and Ion-coupled Magnetic Reconnection in Plasma Turbulence
Electron-only magnetic reconnection was first detected by the Magnetospheric Multiscale (MMS) mission in Earth’s turbulent magnetosheath. Its prevalence in kinetic-scale turbulence has attracted great interest in heliophysics, but also revealed a great challenge in identifying it in turbulence, wher...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2025-01-01
|
| Series: | The Astrophysical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-4357/add882 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849694113526448128 |
|---|---|
| author | Tak Chu Li Yi-Hsin Liu Yi Qi |
| author_facet | Tak Chu Li Yi-Hsin Liu Yi Qi |
| author_sort | Tak Chu Li |
| collection | DOAJ |
| description | Electron-only magnetic reconnection was first detected by the Magnetospheric Multiscale (MMS) mission in Earth’s turbulent magnetosheath. Its prevalence in kinetic-scale turbulence has attracted great interest in heliophysics, but also revealed a great challenge in identifying it in turbulence, where electron flows are often complex. The magnetic flux transport (MFT) method is an innovative method to identify active reconnection in numerical simulations and in situ observations of turbulent plasmas. Here we extend this method to distinguish between electron-only and ion-coupled reconnection. The coupling of magnetic field motion with plasma flows in the diffusion regions sets distinct scales in the MFT velocity. While both forms of reconnection satisfy the MFT signature for active reconnection as MFT inflows and outflows at an X-line, the specific electron-only MFT signature is only an electron-scale MFT outflow along the current sheet normal direction, whereas the specific ion-coupled signature is a two-scale, outer-ion-and-inner-electron-scale MFT outflow in the electron diffusion region, which evolves into a single ion-scale in the ion diffusion region. These signatures are verified in a simulation of gyrokinetic turbulence. The dependence of the MFT outflow on the distance downstream from the X-lines also agrees well with the framework of magnetic field–plasma flow coupling. The new MFT signatures provide a clear and reliable tool for investigating electron-only reconnection in turbulence, independent of the development of electron outflows. They are directly applicable to kinetic and fluid simulations, and have potential application to observations of diffusion region crossings by spacecraft missions such as MMS. |
| format | Article |
| id | doaj-art-1f3dc5f0731e4020a2b60c46d7d8e6ed |
| institution | DOAJ |
| issn | 1538-4357 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj-art-1f3dc5f0731e4020a2b60c46d7d8e6ed2025-08-20T03:20:12ZengIOP PublishingThe Astrophysical Journal1538-43572025-01-01986215410.3847/1538-4357/add882Magnetic Flux Transport Signatures of Electron-only and Ion-coupled Magnetic Reconnection in Plasma TurbulenceTak Chu Li0https://orcid.org/0000-0002-6367-1886Yi-Hsin Liu1https://orcid.org/0000-0001-5880-2645Yi Qi2https://orcid.org/0000-0002-0959-3450Department of Physics and Astronomy, Dartmouth College , Hanover, NH 03755, USA ; tak.chu.li@dartmouth.eduDepartment of Physics and Astronomy, Dartmouth College , Hanover, NH 03755, USA ; tak.chu.li@dartmouth.eduLaboratory for Atmospheric and Space Physics, University of Colorado Boulder , Boulder, CO 80303, USAElectron-only magnetic reconnection was first detected by the Magnetospheric Multiscale (MMS) mission in Earth’s turbulent magnetosheath. Its prevalence in kinetic-scale turbulence has attracted great interest in heliophysics, but also revealed a great challenge in identifying it in turbulence, where electron flows are often complex. The magnetic flux transport (MFT) method is an innovative method to identify active reconnection in numerical simulations and in situ observations of turbulent plasmas. Here we extend this method to distinguish between electron-only and ion-coupled reconnection. The coupling of magnetic field motion with plasma flows in the diffusion regions sets distinct scales in the MFT velocity. While both forms of reconnection satisfy the MFT signature for active reconnection as MFT inflows and outflows at an X-line, the specific electron-only MFT signature is only an electron-scale MFT outflow along the current sheet normal direction, whereas the specific ion-coupled signature is a two-scale, outer-ion-and-inner-electron-scale MFT outflow in the electron diffusion region, which evolves into a single ion-scale in the ion diffusion region. These signatures are verified in a simulation of gyrokinetic turbulence. The dependence of the MFT outflow on the distance downstream from the X-lines also agrees well with the framework of magnetic field–plasma flow coupling. The new MFT signatures provide a clear and reliable tool for investigating electron-only reconnection in turbulence, independent of the development of electron outflows. They are directly applicable to kinetic and fluid simulations, and have potential application to observations of diffusion region crossings by spacecraft missions such as MMS.https://doi.org/10.3847/1538-4357/add882Solar magnetic reconnectionInterplanetary turbulence |
| spellingShingle | Tak Chu Li Yi-Hsin Liu Yi Qi Magnetic Flux Transport Signatures of Electron-only and Ion-coupled Magnetic Reconnection in Plasma Turbulence The Astrophysical Journal Solar magnetic reconnection Interplanetary turbulence |
| title | Magnetic Flux Transport Signatures of Electron-only and Ion-coupled Magnetic Reconnection in Plasma Turbulence |
| title_full | Magnetic Flux Transport Signatures of Electron-only and Ion-coupled Magnetic Reconnection in Plasma Turbulence |
| title_fullStr | Magnetic Flux Transport Signatures of Electron-only and Ion-coupled Magnetic Reconnection in Plasma Turbulence |
| title_full_unstemmed | Magnetic Flux Transport Signatures of Electron-only and Ion-coupled Magnetic Reconnection in Plasma Turbulence |
| title_short | Magnetic Flux Transport Signatures of Electron-only and Ion-coupled Magnetic Reconnection in Plasma Turbulence |
| title_sort | magnetic flux transport signatures of electron only and ion coupled magnetic reconnection in plasma turbulence |
| topic | Solar magnetic reconnection Interplanetary turbulence |
| url | https://doi.org/10.3847/1538-4357/add882 |
| work_keys_str_mv | AT takchuli magneticfluxtransportsignaturesofelectrononlyandioncoupledmagneticreconnectioninplasmaturbulence AT yihsinliu magneticfluxtransportsignaturesofelectrononlyandioncoupledmagneticreconnectioninplasmaturbulence AT yiqi magneticfluxtransportsignaturesofelectrononlyandioncoupledmagneticreconnectioninplasmaturbulence |