Jeong S H, Chang D H, Kim T S, In S R, Lee K W, Jin J T, Chang D S, Oh B H, Bae Y S, Kim J S, Park H T, Watanabe K, Inoue T, Kashiwagi M, Dairaku M, Tobari H, Hanada M
Korea Atomic Energy Research Institute (KAERI), 989-111 Daedeokdaero, Yuseong-gu, Daejeon 305-353, South Korea.
Rev Sci Instrum. 2012 Feb;83(2):02B102. doi: 10.1063/1.3660254.
The first neutral beam (NB) injection system of the Korea Superconducting Tokamak Advanced Research (KSTAR) tokamak was partially completed in 2010 with only 1∕3 of its full design capability, and NB heating experiments were carried out during the 2010 KSTAR operation campaign. The ion source is composed of a JAEA bucket plasma generator and a KAERI large multi-aperture accelerator assembly, which is designed to deliver a 1.5 MW, NB power of deuterium at 95 keV. Before the beam injection experiments, discharge, and beam extraction characteristics of the ion source were investigated. The ion source has good beam optics in a broad range of beam perveance. The optimum perveance is 1.1-1.3 μP, and the minimum beam divergence angle measured by the Doppler shift spectroscopy is 0.8°. The ion species ratio is D(+):D(2)(+):D(3)(+) = 75:20:5 at beam current density of 85 mA/cm(2). The arc efficiency is more than 1.0 A∕kW. In the 2010 KSTAR campaign, a deuterium NB power of 0.7-1.5 MW was successfully injected into the KSTAR plasma with a beam energy of 70-90 keV. L-H transitions were observed within a wide range of beam powers relative to a threshold value. The edge pedestal formation in the T(i) and T(e) profiles was verified through CES and electron cyclotron emission diagnostics. In every deuterium NB injection, a burst of D-D neutrons was recorded, and increases in the ion temperature and plasma stored energy were found.
韩国超导托卡马克先进研究装置（KSTAR）的首个中性束注入系统于2010年部分建成，仅具备其全设计能力的三分之一，并在2010年KSTAR运行期间开展了中性束加热实验。离子源由日本原子能机构（JAEA）桶形等离子体发生器和韩国原子能研究院（KAERI）大型多孔径加速器组件组成，其设计目的是在95keV下提供1.5MW的氘中性束功率。在束注入实验之前，对离子源的放电和束引出特性进行了研究。该离子源在较宽的束导流系数范围内具有良好的束光学性能。最佳导流系数为1.1 - 1.3μP，通过多普勒频移光谱测量的最小束发散角为0.8°。在束流密度为85mA/cm²时，离子种类比为D(+)∶D₂(+)∶D₃(+) = 75∶20∶5。弧效率大于1.0A/kW。在2010年KSTAR运行期间，成功地以70 - 90keV的束能量将0.7 - 1.5MW的氘中性束功率注入到KSTAR等离子体中。相对于阈值，在较宽的束功率范围内观察到了低杂波电流驱动（L - H）转换。通过电荷交换复合光谱（CES）和电子回旋辐射诊断验证了离子温度（T(i)）和电子温度（T(e)）分布中的边缘台基形成。在每次氘中性束注入时，都记录到了一阵D - D中子，并且发现离子温度和等离子体储能增加。
