Abstract
An experimental calibration of flux perturbation has been made with specially prepared neutron detecting foils producing only negligible perturbation in the thermal flux in a graphite medium. The foil material was composed of a 99.8% D2O solution of MnSO4. The manganese in the MnSO4 served as the activating substance. The detecting foils were so prepared as to possess a moderating ratio equal to that of the medium. The calibration was made near the matching point, with foils of various concentrations of manganese, ranging from 1.39 to 13.9 Mn-mg/cc.
The results of experiment indicated that the perturbation near the matching point was fairly insensitive to manganese concentration. The matching concentration was determined graphically.
