Line-intensity ratio measurements of the electron temperature have been successfully made on the CTCC-II spheromak. The electron temperatures obtained in the core plasma are 20-80 eV, which are consistent with the values obtained by Thomson scattering. This measurement has the advantage of giving the time evolution of the electron temperature within a single plasma discharge. In the CTCC spheromak, intermittent instability (stepwise instability) and its relaxation are frequently observed. During the stepwise instability and its relaxation cycles, increase and decrease in the temperature are observed in the current-profile-peaking phase and the nonlinear saturation phase of the n=2 mode. It is demonstrated that the temperature profile in the peripheral plasma can be controlled by an additional magnetic field (choking field), which can reduce the error field in the entrance hole of the flux conserver.
Electron cyclotron emission measurements on T-10 with a grating polychromator