July 27, 2015 to August 21, 2015
Nordita, Stockholm
Europe/Stockholm timezone

Electron-scale Dissipation near the X-line During Magnetic Reconnection and the Upcoming FLARE (Facility for Laboratory Reconnection Experiments) Device

Aug 10, 2015, 9:55 AM
FD5 (Nordita, Stockholm)


Nordita, Stockholm

Keynote Workshop, August 10-14 Morning I


Prof. Hantao Ji (Princeton University)


Despite its disruptive influences on the large-scale structures of space and solar plasmas, the crucial topological changes and associated dissipation during magnetic reconnection take place only near an X-line within thin singular layers on the electron scales. While ion dissipation layers have been frequently detected, the existence of election layers near the X-line and the associated dissipation structures and mechanisms are still an open question, and will be a main subject of the MMS mission. In this presentation, we will revisit the significant discrepancy on the thickness of the electron dissipation layer measured in the MRX experiment [1,2] and in the PIC simulation [3,4]. Although the long wave-length, electromagnetic lower-hybrid drift instabilities has been ruled out as a candidate to explain the discrepancy [5], other two candidates have emerged as possible explanations: (a) 3D flux- rope-like magnetic structures [6] and (b) micro-instabilities at frequencies higher than the lower-hybrid frequency including Debye-scale electrostatic turbulence [7]. Discussions will also include additional results from experimental evidence of electron heating through non- classical mechanisms near the X-line [8], as well as the relevant space observations. We will also present the construction status of the upcoming FLARE device [9] which is designed to access new regimes of magnetic reconnection involving multiple X-lines. The prospective research topics on FLARE will be discussed in relation to the dynamics of the Earth’s magnetosphere. [1] Y. Ren et al., Phys. Rev. Lett. 101, 085003 (2008) [2] H. Ji et al., Geophys. Res. Lett. 35, L13106 (2008) [3] S. Dorfman et al., Phys. Plasmas 15, 102107 (2008) [4] V. Roytershteyn et al., Phys. Plasmas 17, 055706 (2010) [5] V. Roytershteyn et al., Phys. Plasmas 20, 055705 (2013) [6] S. Dorfman et al., Geophys. Res. Lett. 40, 233 (2013); N. Jain, et al., Phys. Plasmas 20, 112101 (2013) [7] J. Jara-Almonte et al., Phys. Plasmas 21, 032114 (2014) [8] J. Yoo et al., Phys. Rev. Lett. 110, 215007 (2013); Phys. Rev. Lett. 113, 095002 (2014) [9] H. Ji and W. Daughton, Phys. Plasmas 18, 111207 (2011)

Primary author

Prof. Hantao Ji (Princeton University)

Presentation materials