注入到外电场的正负电子对的静电不稳定性  

Electrostatic Instability in Positron-Electron Pairs Injected in an External Electric Field

作　　者：汤叔楩[1] 

机构地区：[1]河北科技大学理学院,河北石家庄050054

出　　处：《北京理工大学学报》2005年第z1期289-292,共4页Transactions of Beijing Institute of Technology

基　　金：国家"八六三"计划项目(2002AA639300)

摘　　要：出于脉冲星中粒子加速问题,讨论外电场中注入的正负电子对静电不稳定性．对很强的电场,不能在等 离子体振荡尺度的0阶分布函数忽略空间变化效应．假设在加速(减速)电子(正电子)的恒定外电场以四维速度u0 >0单能地注入电子对．通过解决场的线性扰动和对的分布函数,发现了一个新型不稳定性．u0和外电场确定的 制动时标与等离子体的时标之比R描述不稳定性的性质．这种情况下,增长率是等离子体频率的几倍．Motivated by the particle acceleration problem in pulsars, it is numerically investigated for electrostatic instability of electron-positron pairs injected in an external electric field. The electric field is expected to be so strong that effects of spatial variation cannot be neglected in the 0-th order distribution functions on the scale of the plasma oscillation. The pairs are assume to be injected mono-energetically with 4-velocity u0 > 0 in a constant external electric field by which electrons (positrons) are accelerated (decelerated). By solving linear perturbations of the field and distribution functions of pairs, we find a new type of electrostatic instability. The properties of the instability are characterized by u0 and the ratio R of the braking time-scale (determined by the external electric field) to the time-scale of the plasma oscillation. The growth rate is as large as a few times the plasma frequency.

关 键 词：不稳定性 等离子体 脉冲星 

分 类 号：O534[理学—等离子体物理] O441.4[理学—物理]