Abstract:

Measurements of soft X-ray spectra during Electron Cyclotron Resonance Heating (ECRH) has been achieved on HL-2A tokamak using two independent silicon drift detector (SDD) systems. Electron temperatures are derived from the measured soft X-ray energy spectra. A comparison indicates that the results measured by SDD are consistent with ECE measurements. Experimental results of soft X-ray spectra measure- ment using SDD show that the increment of electron temperature is larger at z=0 than that at z = 16.4cm chord, so, we can conclude that the energy of ECW is deposited dominantly in the core of plasma and electron temperature profile become peaked during on-axis ECRH (B_T=2.4T). The statistic survey of ECRH discharges (2.41T ≤B_T≤2.43T,1.5×10¹⁹m^-3≤n_e≤2.5≤10¹⁹m^-3,300kW≤ECRH power≤600kW) shows that plasma electron temperature rises obviously during on-axis ECRH, especially, in the core of plasma (z=0). It has been observed that the on-axis ECRH can make electron temperature increase up to 30%～80% at z=0 chord and 15%～55% at z=-16.4cm chord.

Key words: Silicon drift detector (SDD), Soft X-ray spectrum, Electron cyclotron resonance heating

摘要：

用两道独立的硅漂移探测器(SDD)测量了HL-2A等离子体在电子回旋加热(ECRH)期间的软X射线能谱，给出了电子温度。SDD软X射线能谱测量系统所测量的结果与电子回旋辐射(ECE)所测量的电子温度分布能较好地相互吻合。SDD软X射线能谱测量结果表明：在轴ECRH期间，等离子体芯部(z＝0)得到加热的迹象比z=-16.4cm处更加显著，由此可推断出在轴ECRH期间ECW的能量主要沉积在等离子体芯部并且电子温度剖面趋于峰化。对2.41T ≤环向磁场B_T≤2.43T, 1.5× 10¹⁹ m^-3≤电子密度n_e≤2.5×10¹⁹m^-3，300kW≤ECRH功率≤600 kW范围的ECRH数据的统计结果表明：ECRH使得等离子体中的电子得到显著的加热，芯部等离子体电子温度可提升30%～80%，z=-16.4cm处的电子温度可提升15%～55%。

关键词: SDD, 软X射线能谱, 电子回旋共振加热