实验利用射频辉光放电产生均匀等离子体,带负电荷的花粉颗粒悬浮在鞘层边界处.通过激光散射法及空间分辨测量得到颗粒的分布,进而得到鞘层分布.实验结果表明,随着玻璃环内径的逐渐增大,颗粒的分布越靠近玻璃环,并且玻璃环中心处等离子体鞘层的凸起越明显.用Matlab可将较大玻璃环内鞘层沿径向分布用四次多项式拟合.实验结果对深入研究尘埃等离子体中带电颗粒的各种复杂运动提供了实验依据.
Uniform plasma is produced by using of radio frequency glow discharge,pollen grains charged negatively suspend at the sheath boundary.The distribution of particles is observed by laser scattering method and spatial resolution measurement,and then the distribution of the sheath is obtained.Experimental results show that with increasing the diameter of the ring,the distribution of the particles close to the glass wall and the convex sheath at the center of the glass ring becomes obvious.The radial distribution of sheath within large glass ring can be fitted with a quartic polynomial by using Matlab.Our results could contribute to the study of the complex motion of charged grains in dust plasma.
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