Approximate Integrals of rf-driven Particle Motion in Magnetic Field.

Dodin, I. Y. ; Fisch, N. J.

Technical Information Center Oak Ridge Tennessee

关键词: Particle motion;    Integrals;    Magneitc fields;    Hamiltonians;    Lagrangian function;   

RP-ID  :  DE2004827917

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

For a particle moving in nonuniform magnetic field under the action of an rf wave, ponderomotive effects result from rf-driven oscillations nonlinearly coupled with Larmor rotation. Using Lagrangian and Hamiltonian formalism, we show how, despite this coupling, two independent integrals of the particle motion are approximately conserved. Those are the magnetic moment of free Larmor rotation and the quasi-energy of the guiding center motion parallel to the magnetic field. Under the assumption of non-resonant interaction of the particle with the rf field, these integrals represent adiabatic invariants of the particle motion.