Electric Field Structures in Density Cavities and Their Interaction With Ions

Details Electric Field Structures in Density Cavities and Their Interaction With Ions Electric Field Structures in Density Cavities and Their Interaction With Ions

May 2001

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001agusm..sm41b10r&link_type=abstract

American Geophysical Union, Spring Meeting 2001, abstract #SM41B-10

Statistics

Computation

2451 Particle Acceleration, 2471 Plasma Waves And Instabilities, 2704 Auroral Phenomena (2407), 7815 Electrostatic Structures, 7867 Wave/Particle Interactions

Scientific paper

There are two observations that are particularly ubiquitous in the auroral ionospheric plasmas: intense lower hybrid fields in density depleted regions localized transverse to the geomagnetic field [1], and transverse energization of ions emanating from the fields in the density depleted regions [2]. A number of rockets flying through the upper ionosphere have observed localized field structures and associated energization of ions. We will present theoretical and computational studies directed towards understanding these observations. In a density gradient, localized intense electric fields can be generated in regions where plasma resonances exist. These resonances occur where the wave frequency matches the local lower hybrid frequency or the upper hybrid frequency. The singularity in the amplitude of the wave at these spatial locations is logarithmic. The appropriate differential equation describing the spatial profile of the fields can be set up for a cold plasma using Maxwell's equations. We are pursuing both numerical and approximate analytical solutions to determine the characteristics of the fields for two cases: where the wave frequency is given and the parallel (to the magnetic field) wavelengths are the eigenvalues to be determined, or vice versa. The analytical solutions make use of a variational principle. The interaction of ions with the localized electric fields is significantly different from their interaction with a plane wave or a broadband spectrum of waves. A wave-particle interaction model has been developed that studies the interaction of energetic ions with spatially localized electric fields. We find that the phase space of the energized ions can be chaotic, and, for long-time interactions, the ions can undergo large energy gains akin to Levy flights. Detailed analytical and numerical results of the interaction of ions with localized field structures will be presented. This work is supported by NSF Grant No. ATM-98-06328. [1] K.L. McAdams et. al, alics Geophys. Res. Lett. 25, 3091 (1998). [2] K.A. Lynch et. al, alics J. Geophys. Res. 104, 28,515 (1999).

Affiliated with

Also associated with

No associations

Rating

Electric Field Structures in Density Cavities and Their Interaction With Ions 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 Electric Field Structures in Density Cavities and Their Interaction With Ions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electric Field Structures in Density Cavities and Their Interaction With Ions will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1277616