Numerical simulation of a system for ion temperature measurement by Thomson scattering in a tokamak
Numerical simulation of a system for ion temperature measurement by Thomson scattering in a tokamak
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托卡马克汤姆逊散射离子温度测量系统的数值模拟
DOI：
10.1063/1.329195
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
M. Green
中科院分区：
文献类型：
--
作者：
R. Watterson;M. Siegrist;M. Dupertuis;P. Morgan;M. Green
对集体激光汤姆逊散射测量托卡马克离子温度进行了数值模拟，采用蒙特卡罗方法模拟了功率谱估计的统计特性。研究了在有限的激光脉冲长度、有限的信噪比、不同的电子和离子温度以及重杂质的存在等因素的影响下，确定离子温度T_i的精度。结果表明，只考虑散射谱的高频部分，可以减轻低频等离子体湍流和重杂质对散射谱的影响(降低所需的外差接收机中频带宽)。总散射功率与总噪声功率之比为1：2就足以测定钛。较高的信噪比对钛测定的准确度提高不大。更长的激光脉冲可以改善钛的值。激光脉冲..。
A numerical simulation of tokamak ion temperature measurement by collective laser Thomson scattering was performed including a Monte‐Carlo technique to model the statistical properties of power spectrum estimation. The accuracy to which the ion temperature Ti, may be determined under the influence of a finite laser pulse length, a limited signal‐to‐noise ratio, unequal electron and ion temperatures, and the presence of heavy impurities was investigated. It is found that the effects of low‐frequency plasma turbulence and heavy impurities on the scattered spectrum may be mitigated (and the required heterodyne receiver intermediate frequency bandwidth reduced) by considering only the high‐frequency portion of the scattered spectrum. A ratio of total scattered power to total noise power of 1 to 2 is shown to be sufficient to determine Ti. A higher signal‐to‐noise ratio provides little enhancement in the accuracy of Ti determination. Improved values of Ti may be achieved by a longer laser pulse. A laser pulse ...