Abstract
<p>Magnetic reconnection is a fundamental plasma physics process which governs energy and mass transfer from the solar wind into the Earth’s magnetosphere. Electron acceleration during reconnection has been widely investigated with multiple mechanisms proposed. Many of these mechanisms involve flux ropes: twisted magnetic field structures formed during reconnection. Drake et al. 2006 suggest that contracting magnetic islands (or flux ropes in 3D) could trap and energise electrons by a Fermi acceleration process.</p><p>Whilst previous missions have observed and characterised flux ropes, the temporal resolution of the data was typically not great enough to study structures in detail, particularly on electron scales. Here we investigate magnetopause flux ropes using data from NASA’s four spacecraft Magnetospheric Multiscale mission (MMS). MMS measures the thermal electron and ion 3D distribution at 30 msec and 150 msec time resolution, respectively, and at spacecraft separations down to a few kilometers.</p><p>We focus on electron pitch angle distributions and examine how they can be used to investigate magnetopause flux ropes. In particular, the distributions are used to identify electron trapping in magnetic mirror structures on the magnetospheric edge of the flux ropes. These features are found to have extended 3D structure along the body of the flux rope. We evaluate possible formation mechanisms, such as the mirror instability, and potential electron acceleration mechanisms, such as betatron and Fermi acceleration. Magnetic mirror structures could represent an important particle acceleration feature for flux ropes and magnetic reconnection.</p>
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.