A method of measuring α_c on fast neutron reactor

The power rise of burst leading edge is measured at super prompt criticality and prompt neutron breeding constant(α) is gained through fitting the curve of power.We calibrate the reactivity of rod at super delay criticality and deduce the pre-load reactivity from the reactivity of rod.The prompt neutron decay constant at delay criticality(αc) and directional difference on CFBR-II are got from deduction of experimental data at super prompt criticality.The measured αc accords with the result of Rosii-α.