Experimental studies were conducted to characterize and improve the performance of the flat-B ECR ion source.The emittance of the source was investigated for the first time.The output beam currents of high-charge-stat...Experimental studies were conducted to characterize and improve the performance of the flat-B ECR ion source.The emittance of the source was investigated for the first time.The output beam currents of high-charge-states of Ar(q>8)were nearly doubled by increasing the plasma electrode aperture from 4mm to 6mm in diameter.To investigate possible enhancements with broadband microwave radiation,a'white'Gaussian noise generator was employed with a TWT amplifier to generate microwave radiation with a bandwidth of~200MHz.The performance of the flat-B ECR ion source was found to be much better with narrow bandwidth radiation when the source was operated in the flat-B region.However,the ion beam intensities and charge state distributions were improved with the broadband radiation when the source was tuned off the flat-B region.展开更多
基于二维张量积区间B样条小波,构造了一种性能良好的小波平板壳单元.在小波单元的构造过程中,用二维区间B样条小波尺度函数取代传统多项式插值,在所构造的区间B样条平面弹性单元和平面M ind lin板单元的基础上组合而成.区间B样条小波单...基于二维张量积区间B样条小波,构造了一种性能良好的小波平板壳单元.在小波单元的构造过程中,用二维区间B样条小波尺度函数取代传统多项式插值,在所构造的区间B样条平面弹性单元和平面M ind lin板单元的基础上组合而成.区间B样条小波单元同时具有B样条函数数值逼近精度高和多种用于结构分析的基函数的特点.数值算例表明:与传统有限元和解析解相比,构造的小波平板壳单元具有求解精度高,单元数量和自由度少等优点.展开更多
基金Supported by the U.S.Department of Energy under contract DE-AC05-00OR22725 with UT-Battelle,LLC
文摘Experimental studies were conducted to characterize and improve the performance of the flat-B ECR ion source.The emittance of the source was investigated for the first time.The output beam currents of high-charge-states of Ar(q>8)were nearly doubled by increasing the plasma electrode aperture from 4mm to 6mm in diameter.To investigate possible enhancements with broadband microwave radiation,a'white'Gaussian noise generator was employed with a TWT amplifier to generate microwave radiation with a bandwidth of~200MHz.The performance of the flat-B ECR ion source was found to be much better with narrow bandwidth radiation when the source was operated in the flat-B region.However,the ion beam intensities and charge state distributions were improved with the broadband radiation when the source was tuned off the flat-B region.
文摘基于二维张量积区间B样条小波,构造了一种性能良好的小波平板壳单元.在小波单元的构造过程中,用二维区间B样条小波尺度函数取代传统多项式插值,在所构造的区间B样条平面弹性单元和平面M ind lin板单元的基础上组合而成.区间B样条小波单元同时具有B样条函数数值逼近精度高和多种用于结构分析的基函数的特点.数值算例表明:与传统有限元和解析解相比,构造的小波平板壳单元具有求解精度高,单元数量和自由度少等优点.