【摘要】 理论分析了无限大引导磁场情况下的薄环形等离子体介质切伦柯夫脉塞。得出了通入相对论电子注时行列式形式的热腔色散方程,并求出了波增长率。针对不同等离子体密度下,对色散方程以及波增长率进行数值计算和模拟验证。研究发现与电子注作用的主要模式为低频等离子体模式中的前两个模式,随着等离子体密度的升高,脉塞中心工作频率升高、增益变大、带宽明显变宽,由模拟结果可以看出:等离子体频率为4.5×1019m-3时对应着最大的输出功率为80 MW,效率为19.75%,频率为15.55 GHz,继续增大等离子体密度虽然可以使输出频率进一步提高,但是同时会使输出功率迅速下降。更多还原

【Abstract】 A cylindrical waveguide filled with thin annular plasma is studied in a strong longitudinal magnetic field.The beam and the annular plasma have been considered as anisotropic dielectric.So the hot cavity dispersion equation can be derived on the basis of the matched boundary conditions and the wave growth rate is obtained by means of equipotential line method.The dispersion equation and the growth rate with different parameters are numerically calculated.The numerical results show the Cherenkov radiation can be produced through the interaction between the former two low frequency plasma modes and the slow space charge wave,and with the increase of the in plasma density,the maser have several merits,such as enhanced output frequency,higher growth rate and significantly broader bandwidth.Finally,particle-in-cell(PIC) simulation is used to validate the numerical results.更多还原