Particle Acceleration Through The Resonance Of High Magnetic Field And High Frequency Electromagnetic Wave And The Application In The Laboratory Astrophysical Physics

Laser plasma interaction has long been a fascinating subfield of plasma physics. Recently developed chirped-pulse amplification(CPA) technology has led to tabletop laser systems producing multi-Terawatt powers and focused irradiances in excess of 1018W/cm , with duration shorter than 100 fs. Many of plasma basic properties will be essentially controlled by the laser field. On the application side, these short-pulse lasers have been used in a variety of applications such as laser-driven particle accelerators, X-ray lasers, harmonic generation, laboratory astrophysical physics and inertial confinement fusion. A brief investigation is given in chapter 1.The present dissertation discusses four issues. The first one is, acceleration mechanisms of electrons in combined strong axial magnetic fields and circularly polarized laser pulse fields are investigated by solving the dynamical equations of the relativistic electrons both numerically and analytically. We find that the electron acceleration depends not only on the laser intensity, but also on the ratio between electron Larmor frequency and laser frequency. As the ratio equals to unit, a clear resonance peak is observed, that is the laser-magnetic resonance acceleration (LMRA). Away from the resonance regime, the strong magnetic fields still affect the electron acceleration dramatically. We derive an approximately analytical solution of the relativistic electron energy in adiabatic limit, which provides a full understanding of the above interesting new phenomena. Application of our theory in fast ignition of inertial confinement fusion is discussed. This will be presented in chapters 2-3.The second one is, the approximate analytical solution of the relativistic electron energy from LMRA has a good application in astrophysical physics. In typical perimeter of pulsar magnetospheres, the mechanism provide chance to allow particles to increase their energies through the resonance of high magnetic field and high frequency electromagnetic wave (EMRA) in each electromagnetic wave period. The energy spectra of the accelerated particles exhibit the synchrotron radiation behaviour. These can help to understand the remaining emission of high energy electron from radio pulsars within supernova remnants. This presents in chapter 4.The third one is, we use LMRA mechanism to explain the electron depends on the laser polarization. In addition to the ponderomotive acceleration of highly relativistic electrons at interaction of very short and very intense laser pulses, a further acceleration is derived from the interaction of these electron beams with the spontaneous magnetic fields of about 100 MG.This additional acceleration is the result of a laser-magnetic resonance acceleration (LMRA) around the peak of the azimuthal magnetic field. This causes the electrons to gain energy within a laser period. Using a Gaussian laser pulse, the LMRA acceleration of the electrons depends on the laser polarization. Since this is in the resonance regime, the strong magnetic fields affect the electron acceleration considerably. The mechanism results in good collimated high energetic electrons propagating along the center axis of the laser beam as has been observed by experiments and is reproduced by our numerical simulations. This presents in chapter 5.The fourth one is, we present the possible periodic solutions and the solitary wave solutions of the cubic-quintic nonlinear Schrodinger equation. Corresponding to five types of different structures of the pseudo-potentials, five types of periodic solutions are given explicitly. And five types of solitary wave solutions are also obtained explicitly from the limiting procedures of the periodic solutions. This will benefit to study the generation of fast ions or electrons which produce from the soliton breaking when the plasma irradiated by the high-intensity laser pulse.Laser plasma interaction is a typical nonlinear problem and one of the key issues in laser fusion. In fast ignitor concept, the most important subjects are to investigate ho...