Particle Simulations of Plasma Wave Instabilities II

1. Name of Database:  Particle Simulations of Plasma Wave Instabilities­¶: 
                      Electron beam instability as generation mechanism of 
                      electrostatic solitary waves in the magnetotail

2. Institution:¡¡Radio Science Center for Space and Atmosphere, Kyoto University

3. Contents of Database: ¡¡

The database contains six examples of simulation runs of electron beam instabilities as typically 
found in space plasmas. These instabilities play important roles in the energy transfer and 
dissipation in space plasmas.  Nonlinear evolutions of these instabilities are reproduced by 
one-dimensional particle simulation with periodic boundaries.   As a result of the nonlinear 
evolutions, electrostatic solitary waves (ESW) are generated.  ESW are very stable electrostatic 
potentials, traveling over a long distance along the ambient magnetic field.  These ESW are 
frequently observed in the plasma sheet boundary layer as reported by the GEOTAIL spacecraft.  
Since ESW appear as broadband noise in frequency spectra, they were also observed as broadband 
electrostatic noise (BEN) in the previous spacecraft observations.  Recent spacecraft observations 
in other regions of the magnetosphere show that there exist ESW associated with fluxes of high 
energy particles, which verifies that the nonlinear processes as demonstrated by the present 
simulations are taking place ubiquitously in space plasmas. 

All computations were performed on the KDK computer system at Radio Science Center for Space and 
Atmosphere, Kyoto University.

4. Examples of Database:

An example of frames showing the simulation results is given below.  The top panel is a contour plot 
of the velocity distribution function f(X, Vx) in the velocity of phase space X-Vx,.  The middle and 
lower panels are spatial profiles of the electric field Ex(x) and electrostatic potential ¦µ.



Detailed description of the simulation runs are found in the following reference.

Y. Omura, H. Matsumoto, T. Miyake and H. Kojima, Electron Beam Instabilities as Generation Mechanism 
of Electrostatic Solitary Waves in the Magnetotail, Journal of Geophysical Research, vol. 101, 
pages 2,685-2,697, 1996.

The simulation code used in producing the present database. is a one-dimensional elelctrostatic coode.  
Detailed description of the code is found in the following reference.

Y. Omura and H. Matsumoto, KEMPO1: Technical Guide to One-Dimensional Electromagnetic Particle Code, 
Computer Space Plasma Physics: Simulation Techniques and Softwares, edited by H. Matsumoto and 
Y. Omura, pages 21-65, Terra Scientific, Tokyo, 1993.
http://www.terrapub.co.jp/e-library/cspp/index.html

5. Contact:

¡¡Yoshiharu Omura
¡¡RASC, Kyoto University, 
¡¡Gokasho, Uji, 611-0011, Japan
¡¡Phone:  +81-774-38-3811
¡¡E-mail:  omura[AT]kurasc.kyoto-u.ac.jp

6. Public Offering of Database:

¡¡http://center.stelab.nagoya-u.ac.jp/web1/sramp/cdrom/sm0005/index.html  
  Also see:  Home Page of Geotail Plasma Wave Instrument
¡¡http://www.rish.kyoto-u.ac.jp/space/gtlpwi/  

S-RAMP Database Catalog.

S-RAMP Home Page.