Electron Heating and Current Drive by Electron Bernstein Waqves

普通（O-）和异常（X-）模式等电磁波通常用于电子回旋共振加热（ECRH），其具有密度限制，即所谓的截止密度。因此，这些模式在高密度区域是无用的。希望开发另一种加热方案，用于产生和加热高密度等离子体，而不考虑截止密度。电子伯恩斯坦波（EBW）是一种静电波，它的优点是没有截止密度，即使在低电子密度的几个10 eV的吸收效率是相当高的。在这项研究中，射线追踪代码计算的吸收效率已经开发的环形配置，以研究EBW加热。计算结果表明，功率吸收曲线对等离子体参数（电子密度和温度）的敏感性较弱，这有利于实验验证O-X-B加热。在 关于我们 在螺旋系统中，由于其磁场结构，通过从低场侧端口沿环形方向倾斜地发射束，可以实现慢X-B模式加热。在球环中，电子束焊在电子加热和电流驱动方面具有重要作用，因为由于等离子体的高介电特性，很难使用传统的ECRH。在等离子体实验中，在Heliotron J和LHD装置中观察到了X-B模式转换加热。在Heliotron J中，即使在核心等离子体区域中不存在电磁谐振时，存储的能量也达到与二次谐波X模式ECRH相当的1 kJ。这可以通过缓慢的X-B模式转换加热来解释。在LHD中，当束流沿环向倾斜发射时，得到了X-B模转换加热的实验结果。根据FFT分析，功率吸收轮廓在ECR层的低场侧的局部区域中达到峰值。少

The electromagnetic waves such as the ordinary (O-) and extraordinary (X-) modes are conventionally used for electron cyclotron resonance heating(ECRH), which has a density limit so called cutoff density. Therefore these modes are not useful at high density regime. It is desirable that another heating scheme should be developed for the production and heating of high density plasma regardless of cut off density. The electron Bernstein waves(EBW) is a electrostatic wave which has advantages that there is no cutoff density and that the absorption efficiency is quite high even at low electron density of a few 10 eV.In this research, ray tracing codes to calculate the absorption efficiency have been developed for toroidal configurations in order to study the EBW heating. The calculation results indicate that the power absorption profile is weakly sensitive to plasma parameters such as electron density and temperature, which is favorable for experimentally demonstrating the O-X-B heating. In … More helical systems, the slow X-B mode heating is possible by launching the beam obliquely in the toroidal direction from low field side port due to its magnetic field structure. In spherical torus, the EBW has an important role on the electron heating and current drive, since it is difficult to use the conventional ECRH owing to high plasma dielectric properties. Similarly as helical systems, it is numerically demonstrated that the O-X-B heating is possible, and the dependence on the plasma parameters and magnetic field is obtained.In plasma experiments, the X-B mode conversion heating has been experimentally observed in the Heliotron J and LHD devices. In Heliotron J, the stored energy reaches 1 kJ comparable to the second harmonic X-mode ECRH even when the electromagnetic resonance does not exist in the core plasma region. This can be explained by the slow X-B mode conversion heating. In LHD, some experimental results implying the X-B mode conversion heating has be obtained when the beam is launched obliquely in the toroidal direction. According to the FFT analysis, the power absorption profile is peaked in a localized area of the low field side from ECR layer. Less