Authors:J. Rao, E. Senthilvadivu, N. Seshadreesan, R. Acharya, C. Venkatasubramani, and A. Reddy
The pneumatic fast transfer system position at KAMINI reactor, Indira Gandhi Centre for Atomic Research, India was characterized
by determining the epithermal neutron flux shape factor (α) and the sub-cadmium to epithermal neutron flux ratio (f) for k0-based Neutron Activation Analysis (k0-NAA). For determination of α value, bare, Cd-ratio and Cd-cover methods were employed using dual and multi monitors namely
Au, Zr and Zn. For calculation of f, Au and Zr monitors were used in the case of bare method and Au monitor was used for cadmium ratio and cadmium cover methods.
The determined α-value of PFTS indicated a hard epithermal neutron spectrum and the f value indicated about 96 % thermal neutron
component. For validation of k0-NAA method, reference materials namely NIST SRM 1646a (Estuarine Sediment) and BCS Nb-stabilized Stainless Steel (BCS/SS
No.261/1) were analyzed. The percentage errors of the determined concentration values of elements were within ±5 % with respect
to the certified values and the Z-score values at 95 % confidence level were within ±2 in most of the cases.