Nonlinear Processes in Geophysics www.nonlin-processes-geophys.net 1023-5809 1607-7946 12 1 2005 10.5194/npg-12-101-2005 http://www.nonlin-processes-geophys.net/12/101/2005/ http://www.nonlin-processes-geophys.net/12/101/2005/npg-12-101-2005.html http://www.nonlin-processes-geophys.net/12/101/2005/npg-12-101-2005.pdf 101 115 2005-01-27 Quasiadiabatic description of nonlinear particle dynamics in typical magnetotail configurations D. L. Vainchtein J. Büchner A. I. Neishtadt L. M. Zelenyi Space Research Institute, ul.Profsouznaya, 84/32, Moscow, Russia, GSP-7, 117997 Department of Mechanical & Environmental Engineering, University of California, Santa Barbara, CA 93106, USA Max Planck Institut für Aeronomie, Max-Planck-Str. 2, D-37191 Katlenburg-Lindau, Germany In the present paper we discuss the motion of charged particles in three different regions of the Earth magnetotail: in the region with magnetic field reversal and in the vicinities of neutral line of <i>X</i>- and <i>O</i>-types. The presence of small parameters (ratio of characteristic length scales in and perpendicular to the equatorial plane and the smallness of the electric field) allows us to introduce a hierarchy of motions and use methods of perturbation theory. We propose a parameter that plays the role of a measure of mixing in the system.