Calibration of neutron yield activation measurements at Joint European Torus

Neutron transport calculations are performed using the Monte Carlo particle trajectory sampling method (the MCNP code) to determine the neutron fluences and energy distributions at different locations in the Joint European Torus (JET) tokamak. The primary purpose of these calculations is to calibrate the activation measurements used to determine the absolute fusion neutron yield from the JET plasma. In this paper the calculated neutron activation response coefficients are presented for three different materials used in neutron yield determination for plasmas producing 2.5- and 14-MeV neutrons. The accuracy of the calibration derived from the neutron transport calculations is tested by comparing the present results for the total 2.5-MeV neutron yield with those obtained with calibrated fission chamber: overall agreement at the +-15% level is demonstrated