Propagation speed of rotation signals for field lines undergoing magnetic reconnection
2013 (English)In: Physics of Plasmas, ISSN 1070-664X, Vol. 20, no 10, 102113- p.Article in journal (Refereed) Published
Reconnection is associated with two bending of the magnetic field lines. Considering the usual plane of a 2D reconnection simulation, the first bending is in-plane and produces the needed topological changes by bringing oppositely directed filed lines in proximity. The second is typical of fast reconnection and is out of plane, leading to the formation of the Hall magnetic field. This second rotation has recently been observed to proceed at superAlfvenic speeds and to carry substantial energy fluxes (Shay et al., Phys. Rev. Lett. 107, 065001 (2011)). We revisit these rotations with a new diagnostics based on dispersing a multitude of virtual probes into a kinetic simulation, akin the approach of multi spacecraft missions. The results of the new diagnostics are compared with the theory of characteristics applied to the two fluid model. The comparison of virtual probes and the method of characteristics confirm the findings relative to the out of plane rotation and uncover the existence of two families of characteristics. Both are observed in the simulation. The early stage of reconnection develops on the slower compressional branch and the later faster phase develops on the faster torsional branch. The superAlfvenic signal is only relevant in the second phase.
Place, publisher, year, edition, pages
2013. Vol. 20, no 10, 102113- p.
Hall magnetic field, Kinetic simulation, Magnetic field line, Magnetic reconnections, Method of characteristics, Multi-spacecraft mission, Out-of-plane rotation, Topological changes
IdentifiersURN: urn:nbn:se:kth:diva-136512DOI: 10.1063/1.4825132ISI: 000326644100031ScopusID: 2-s2.0-84887221020OAI: oai:DiVA.org:kth-136512DiVA: diva2:676677
FunderEU, FP7, Seventh Framework Programme, 263340
QC 201312062013-12-062013-12-052013-12-06Bibliographically approved