感应磁场压缩下氢等离子体中巴耳末系谱线的斯塔克加宽

本工作研究感应磁场压缩下,氢等离子体中的巴耳末系谱线的斯塔克加宽。电容器对围绕在放电管外部的线圈放电,产生交变轴向磁场,使放电管中氢气离化、压缩与加热。放电周期14微秒,放电电压20千伏,最大电流165千安,初始工作气压2.0×10^-1毫米汞高。用照相方法研究H_β和H_γ的轮廓。这些谱线有显著的加宽。在整个发光阶段中,H_β的平均半宽度为14—16(埃),H_γ为18—19(埃),相应的离子密度为1.7—2.5×10¹⁶厘米^-3。实验轮廓与Griem,Kolb和Shen的理论较为接近,与Holtsmark理论相差较远。光电测量进一步表明:H_β的轮廓随着时间而改变,相应的离子密度亦在改变。在放电的第三半周期初级电流极大时,离子密度最大,达到3.2×1O¹⁶厘米^-3,为初始氢原子密度的2.2倍。

THE STARK BROADENING OF BALMER LINES IN A HYDROGEN PLASMA PRODUCED BY INDUCED MAGNETIC FIELD

The Stark broadening of Balmer lines in a hydrogen plasma produced by induced magnetic field has been investigated. A condenser bank discharging into the coil surrounding the discharge tube, produces an alternating axial magnetic field which ionizes, compresses, and heats the hydrogen in the tube. The working conditions are: initial pressure of hydrogen, 2.0×10^-1mm Hg; charging voltage, 20 kV; discharge period, 14 microseconds; maximum current, 165 kA. Profiles of the spectral lines of H_β and H_γ are studied by the photographic method. These lines are considerably broadened. In the whole luminous stage, the mean half-widths of H_β and H_γ are 14-16? and 18-19? respectively, corresponding to an ion density of 1.7-2.5×10¹⁶cm^-3. The experimental profiles agree better with Griem, Kolb, and Shen's theory than with Holtsmark's theory. Photo-electrical measurements show that the profile of H_β changes with time, accordingly the ion density changes also. At the primary current maximum of the third half-period of discharge, the ion density reaches a peak value of 3.2×10¹⁶cm^-3 which is 2.2 times the initial density of hydrogen atoms.