During the impurity radiation, the density perturbation driven by density gradient couples with the temperature one and then affects the electrostatic potential one.
电子密度梯度直接影响密度涨落，并通过杂质辐射与温度涨落相互耦合，进而影响静电势涨落。
2
The energy equation is solved by the zonal method, and the inverse radiation problem is solved through the minimization of performance function with the conjugated gradient method.