Focused electron beam transport through a long narrow metal tube at elevated pressures in the forevacuum range  

作　　者：Ilya BAKEEV Kirill KARPOV Aleksandr KLIMOV Efim OKS Aleksey ZENIN 

机构地区：[1]Tomsk State University of Control Systems and Radioelectronics,Tomskaâ634050,Russia [2]Institute of High Current Electronics,Siberian Branch,Russian Academy of Sciences,Tomskaâ634055,Russia

出　　处：《Plasma Science and Technology》2023年第1期128-134,共7页等离子体科学和技术（英文版）

基　　金：Russian Science Foundation(No.21-79-10217)。

摘　　要：We present here our investigations of the features of focused electron beam transport in free space at elevated pressures of a few pascals.We have explored the effect of the beam accelerating voltage,operating gas pressure,and magnetic focusing upon the trajectory of beam electrons in the crossover region,in particular on the beam convergence and divergence angles.It is shown that for the forevacuum pressure range of 2-5 Pa explored,a distinctive feature of the propagation of a focused electron beam with a current of up to 20 mA at an accelerating voltage of 10-20 kV is the difference in the angles of convergence(before the focus)and divergence(after the focus).Whereas at a low pressure of 2 Pa the divergence angle is smaller than the convergence angle,as the pressure increases the divergence angle increases and for pressures greater than 5 Pa the divergence angle is greater than the convergence angle.The results obtained were used in experiments on electron beam transport through a long narrow metal tube with a diameter of 5.8-9.2 mm and length of 10-30 cm.We show that for a 30 cm long tube of 7.5 mm diameter,the focused beam transmission can exceed 70%.

关 键 词：focused electron beam plasma electron source forevacuum pressure range long metal tube 

分 类 号：O17[理学—数学]