Experimental and Numerical Study of Asymmetric Vortex Merger in a Pure Electron Plasma

reportActive / Technical Report | Accession Number: ADP012544 | Open PDF

Abstract:

The merging of an intense localized vortex with an extended vortex is investigated by means of an experimental analysis performed on a Malmberg-Penning trap with photocathode, and numerical simulations with a two-dimensional 2D particle in cell PIC code. The study is restricted to highly nonlinear conditions, where the perturbative approach does not hold. A very good agreement between experimental results and simulations is obtained. It is found that the localized vortex is firstly wrapped around by the extended vortex, then moves towards the center of the system, eventually approaching an almost stationary state of rotation characterized by the formation of vorticity holes. During the whole evolution the extended vortex gains energy from the field surrounding the vortices, while the energy of the localized vortex remains constant.

Author(s):
Amoretti, M. ; Durkin, D. ; Fajans, J. ; Pozzoli, R. ; Rome, M.
Author Organization(s):
CALIFORNIA UNIV BERKELEY DEPT OF PHYSICS
Descriptive Note:
Final rept. 15 Apr 2001-31 Mar 2002
Supplementary Note:
This article is from CP606, Non-Neutral Plasma Physics IV, p459-463, 2001. Pub. in AIP Conference Proceedings: volume 606. Prepared in cooperation with Ernst-Moritz-Arndt-Universitaet, Greifswald, Germany; I.N.F.M. (U.d.R. Milano Universita) and Dipartimento di Fisica, Universita degli Studi di Milano, Italy. This article is from ADA404831 Non-Neutral Plasma Physics 4. Workshop on Non-Neutral Plasmas (2001) Held in San Diego, California on 30 July-2 August 2001
Pagination:
0005

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release

RECORD

Collection: TR
Identifying Numbers
Contract/Grant Number(s):
N00014-01-1-0729
Monitor Series:
ONR
 Subject Terms
Joint Capability Areas:
JCA_1_Force Support; JCA_5.3_Planning; JCA_5_Command and Control
Communities of Interest:
Energy and Power Technologies
Descriptor(s):
*EXPERIMENTAL DATA, *PLASMAS(PHYSICS), *NUMERICAL ANALYSIS, *ASYMMETRY, COMPUTERIZED SIMULATION, MAGNETIC FIELDS, SYMPOSIA, TWO DIMENSIONAL, ELECTRON DENSITY, TURBULENCE, CHARGED PARTICLES, VORTICES, ELECTRON ENERGY, PURITY, NONLINEAR SYSTEMS, EVOLUTION(GENERAL), ITALY, ROTATION, PHOTOCATHODES
Field(s)/Group(s):
Plasma Physics and Magnetohydrodynamics
Keyword(s):
COMPONENT REPORT, FOREIGN REPORTS, *VORTEX MERGER, *ELECTRON PLASMA, MALMBERG PENNING TRAP, PIC(PARTICLE IN CELL), PIC COMPUTER PROGRAM
Report Date:
2002 Jun 24
Creation Date:
2002 Sep 04