Conferences - Seminars

  Wednesday 18 June 2014 10:30 - 11:30 PPB 019

"Magnetic reconnection via stochastic plasmoid chains"

By Dr. Nuno Loureiro
Instituto Superior Técnico Lisbon, Portugal

Magnetic reconnection is the topological reconfiguration of the magnetic field in a plasma, accompanied by the violent release of energy and particle acceleration. Reconnection is as ubiquitous as plasmas themselves, with solar flares perhaps the most popular example. Other fascinating processes where reconnection plays a key role include the magnetic dynamo, geomagnetic storms and the sawtooth crash in tokamaks.

Over the last few years, the theoretical understanding of magnetic reconnection in large-scale fluid systems has undergone a major paradigm shift. The steady-state model of reconnection described by the famous Sweet-Parker (SP) theory, which dominated the field for 50 years, has been replaced with an essentially time-dependent, bursty picture of the reconnection layer, dominated by the continuous formation and ejection of multiple plasmoids. Whereas in the SP model reconnection was predicted to be slow, a major implication of this new paradigm is that reconnection in fluid systems is fast (i.e., independent of the Lundquist number), provided that the system is large enough.

In this talk, I will review the recent developments in reconnection that led to this essentially new framework, and briefly discuss some of the challenges that remain at the frontier of this subject.

Organization Prof. P. Ricci

Contact Prof. P. Ricci

Accessibility Informed public

Admittance Free