Response function generation for Cerenkov radiation production and transport in a TRIGA coolant channel

Abstract

This study produces a response function that correlates the electron flux within a coolant channel in a TRIGA reactor to the amount of observable, visible Cerenkov light above the core. This response function is to be used in a study on using Cerenkov detection for spatial power profiling in a reactor. 23 electron energy bins and 16 spatial bins are used to create a matrix of 368 correlation factors that comprises the response function. It was tested to verify self-consistency by accounting for 92% of the Cerenkov photons 2 m above the core. The strength of the coupling between the Cerenkov above a coolant channel and the fission density in the core was also analyzed and it was found that in an 8 × 8 fuel pin lattice, 60.5% of the Cerenkov above a channel comes from gammas produced within the four surrounding pins and 88.1% comes from the closest 16 pins.