Neutronic analysis for calibration of ITER in-vessel neutron flux monitor with microfission chamber

Ishikawa, Masao; Kondoh, Takashi; Kusama, Yoshinori; Bertalot, L.*

Neutronic analysis is performed for calibration of the in-vessel neutron flux monitor in ITER, the Microfission Chamber (MFC). The transfer system of a neutron generator, which consists of two toroidal rings and a neutron generator holder, has been designed and its effect on the detection efficiency of the MFC is estimated through neutronic analysis with MCNP. The result indicates that the designed transfer system is unaffected for the detection efficiency of the MFC. calibrations for the point by point method and the rotation method are simulated and compared through neutronic analysis. It is found that the rotation method is appropriate for full calibration because this method has the advantage that the calibration time can be shortened and all neutron flux monitors can be calibrated simultaneously.