Experimental validation of the neutronic parameters in the Jordan subcritical assembly

Following the construction of the Jordan Subcritical Assembly (JSA) on the campus of the Jordan University of Science and Technology (JUST); a detailed experimental study of the facility was performed to measure different reactor parameters. In this paper, the reactivity and activation reaction rate in JSA were determined experimentally and then validated with the calculated results from Monte Carlo Simulation Radaideh et al. (2018a). The reactivity and criticality analysis were implemented using the source jerk method, while the foil activation technique was used for activation reaction rate and flux characterization. The experimental subcritical reactivity in dollars was −5.498 ± 0.045 while keff for the facility was 0.96476 ± 0.00771. The multiplication factor calculated using Monte Carlo codes of JSA was 0.96553 ± 0.00002. In addition, it was found that the source jerk results had large uncertainties due to the counting error. 115In foils were used to measure the activation reaction rate. The absolute axial and radial reaction rates were measured by averaging the measured counts for three photo-peaks of 116mIn. The experimental results were validated by the calculated reaction rates from MCNP5. The error in the activation reaction rate measurements were dominated by the peak area measurement error. The calculated and measured activation reaction rate results demonstrated very good agreement with a maximum deviation of approximately 11% in both directions. In this work, the neutron source strength was experimentally determined using the foil activation technique. The value estimated for the source was 1.02×106±0.9% (n/s) which is very close to the reported value.