Neutral beam tomography using maximum entropy method

Abstract

A tomography algorithm to maximize the entropy of image using lagrangian multiplier technique and conjugate direction line minimization method was used for the reconstruction of 2D spatial distribution of intense neutral beams of KSTAR NBI (Korea Superconducting Tokamak Advanced Research Neutral Beam Injector). A possible detection system was modeled by system geometry parameters and numerical simulations were done to test the reconstruction fidelity of simulated beam profiles. First of all, we simulated with changes of number of cameras and 11 cameras were adopted from this simulation. The simulations with changes of noises, horizontal divergences, and power rates were also done and their relationships with reconstruction fidelity were shown.