Neutronic analysis for in-situ calibration of the in-vessel neutron monitor using microfission chamber for ITER

Ishikawa, Masao; Kondoh, Takashi

Neutronic analysis is performed for in-situ calibration of the in-vessel neutron flux monitor in ITER, the Microfission Chamber (MFC). 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. However, this method is not easy to compare with neutronic analysis. So, the point by point method should be performed prior to full calibration to check the accuracy of the MCNP model and for a mock up experiment of the full calibration. Cooling water in the blanket module could significantly affect the detection sensitivity. These results suggest cooling water should be filled in the blanket module in the same way as the ITER operations when the in-situ calibration is performed.