High resolution measurements of neutral density and ionization rate in the Alcator C-Mod tokamak
High resolution measurements of neutral density and ionization rate in the Alcator C-Mod tokamak
复制标题
Alcator C-Mod 托卡马克中的中性密度和电离率的高分辨率测量
DOI：
10.1063/1.1319362
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发表时间：
2001
影响因子：
1.6
通讯作者：
J. Terry
中科院分区：
文献类型：
--
作者：
R. Boivin;J. Hughes;B. LaBombard;D. Mossessian;J. Terry
Alcator C-Mod 托卡马克装置上安装了两个新的高分辨率探测器，用于测量主室等离子体边缘的中性密度和电离率。使用对紫外光敏感的硅探测器和透射峰值为 1216 A 的非常窄的滤光片，测量中性氘（和氢）发出的莱曼 α 辐射。探测器由 20 个通道阵列组成，可在外中板下方 12.5 厘米和内中板上方 10 厘米处切向观察等离子体。使用 1mm×3mm 狭缝进行成像，标称径向分辨率分别为 2 毫米和 3 毫米。局部发射率是通过标准阿贝尔反演技术获得的。采用众所周知的支化比，并使用测量的局部电子密度和温度，以类似的径向分辨率推断出中性密度和电离率。讨论了设置的细节和结果对等离子体条件的敏感性。
Two new high resolution detectors have been installed on the Alcator C-Mod tokamak to measure the neutral density and ionization rate at the edge of the main chamber plasma. Using a silicon detector sensitive to UV light, and a very narrow filter with transmission peaking at 1216 A, the Lyman alpha radiation emanating from neutral deuterium (and hydrogen) is measured. The detectors consist of 20 channel arrays which view the plasma tangentially 12.5 cm below the outer midplane, and 10 cm above the inner midplane. The imaging is performed using a 1 mm×3 mm slit, which gives a nominal radial resolution of 2 and 3 mm, respectively. The local emissivity is obtained via a standard Abel inversion technique. Employing well-known branching ratios, and using measured local electron density and temperature, the neutral density and ionization rate are inferred with similar radial resolution. Details of the setup and sensitivity of the results to plasma conditions are discussed.