Geospace Environmental Modeling (GEM) magnetic reconnection challenge

Physics – Plasma Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

441

Magnetospheric Physics: Magnetopause, Cusp, And Boundary Layers, Magnetospheric Physics: Magnetotail, Space Plasma Physics: Magnetic Reconnection, Space Plasma Physics: Numerical Simulation Studies

Scientific paper

The Geospace Environmental Modeling (GEM) Reconnection Challenge project is presented and the important results, which are presented in a series of companion papers, are summarized. Magnetic reconnection is studied in a simple Harris sheet configuration with a specified set of initial conditions, including a finite amplitude, magnetic island perturbation to trigger the dynamics. The evolution of the system is explored with a broad variety of codes, ranging from fully electromagnetic particle in cell (PIC) codes to conventional resistive magnetohydrodynamic (MHD) codes, and the results are compared. The goal is to identify the essential physics which is required to model collisionless magnetic reconnection. All models that include the Hall effect in the generalized Ohm's law produce essentially indistinguishable rates of reconnection, corresponding to nearly Alfvénic inflow velocities. Thus the rate of reconnection is insensitive to the specific mechanism which breaks the frozen-in condition, whether resistivity, electron inertia, or electron thermal motion. The reconnection rate in the conventional resistive MHD model, in contrast, is dramatically smaller unless a large localized or current dependent resistivity is used. The Hall term brings the dynamics of whistler waves into the system. The quadratic dispersion property of whistlers (higher phase speed at smaller spatial scales) is the key to understanding these results. The implications of these results for trying to model the global dynamics of the magnetosphere are discussed.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Geospace Environmental Modeling (GEM) magnetic reconnection challenge does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Geospace Environmental Modeling (GEM) magnetic reconnection challenge, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Geospace Environmental Modeling (GEM) magnetic reconnection challenge will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1008643

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.