Observatoire de Paris Institut national de recherche scientifique français Univerité Pierre et Marie Curie Université Paris Diderot - Paris 7

In situ observations of magnetic reconnection in near-Earth space

Tuesday 19 April 2011, by Alessandro Retinò (LPP, École Polytechnique, Palaiseau)

Tuesday 26 April 2011 à 11h00 , Lieu : Salle de confĂ©rence du bât. 17

Magnetic reconnection is a universal process occurring at current sheets in astrophysical plasmas, where small-scale changes in the topology of the magnetic field lead to large-scale transport of plasma, acceleration of plasma jets, plasma heating and non-thermal particle acceleration. Reconnection is observed in the solar corona, in the solar wind, in planetary magnetospheres and is considered to play an important role in many other distant objects. Despite of many remote and in situ observations of reconnection, however, a number of key issues are still open; among them the microphysics, the mechanisms of non-thermal particle acceleration and the relationship with turbulence. Solving these issues from an experimental point of view requires in-situ observations of particle distributions functions and electromagnetic fields in reconnection regions, that are only available in the solar system through spacecraft measurements. Here we present some examples of in-situ observations, focusing on the near-Earth space.