_ A so-called electron diffusion region. It is a boundary just a few kilometres thick that occurs at an altitude of approximately 60000 kilometres above the Earth’s surface, where electrons can be accelerated to approximately one hundredth the speed of light. On 25 January 2005, and for nineteen times in one hour, the Cluster quartet found themselves engulfed in an electron diffusion region.http://www.esa.int/esaCP/SEM8DA9ATME_index_1.html
_Electron Diffusion Region (EDR)- In a plasma (a gas of charged particles), during magnetic recon[figuration], magnetic field lines of opposite direction ... [reconfigure], forming an X-line magnetic topology. The new... field lines accelerate the plasma away from the X-line
. (Credit: Center for Visual computing, Univ. of California Riverside)
http://www.sciencedaily.com/releases/20 ... 230056.htm
“Understanding the structure of the diffusion region and its role in controlling the rate at which magnetic energy is converted into particle energy remains a key scientific challenge,” says Dr Michael Shay, University of Delaware, USA.
Until recently, theoretical scientists believed that the electron diffusion region was relatively tiny (width about 2 km, length about 10 km)...
Comparison between observations and simulation
On 14 January 2003, the four Cluster satellites were crossing the magnetosheath, a turbulent plasma region located just outside Earth’s magnetosphere, when they encountered an electron diffusion region. The length of the observed region measured 3000 km, 300 times longer than the earlier theoretical expectations and four times longer than seen in recent simulations. Nevertheless, the observations strongly support new simulations.
Apparently they have been working on this data forawhile and have just recently decided that these cusps
, forming periodically at junctures of the solar magnetic flux and the earth's magnetosphere, can form "portals" which conduce a rush of ions ("accelerate the plasma away from the X-line") right through our magnetosphere.
Here the electrons are provided by the current sheets which collimate the earth-magnetosphere like the layers of a big green-onion / shallot,
~ but comes to mind the physics of an old TV picture tube where diffuse electrons (from the the wall outlet) are collimated by the magnetic yolks (cusps) and and shot down tube, like a portal to our eyeballs.
Observing the Electron Diffusion Regionwith MMS