Fast neutron fluence monitoring in the exposure channel F19 of the TRIGA Mark II reactor in Ljubljana

In the last few years mainly irradiations were performed in the vertical exposure channel F19. In the meanwhile, remote parts of the core were altered several times; however no essential changes were made to the core in the near surroundings of this channel. Because the fast neutron fluence was monitored with slow neutron detection material, there appeared a doubt that these modifications might have introduced appreciable errors in the results. In this contribution experimental results showing that this fear was unfounded will be presented.(author)