Local neutron flux distribution measurements by wire-dosimetry in the AMMON experimental program in the EOLE reactor

Dosimetry measurements were carried out during the AMMON experimental program, in the EOLE facility. Al-0.1 wt% Au wires were positioned along curved fuel plates of JHR-type assemblies to investigate the azimuthal and axial gold capture rate profiles, directly linked to the thermal and epithermal flux. After irradiation, wires were cut into small segments (a few mm), and the gold capture rate of each part was measured by gamma spectrometry on the MADERE platform. This paper presents results in the 'hafnium' configuration, and more specifically the azimuthal flux profile characterization. In the 'hafnium' configuration, a hafnium rod was inserted in the center of the central assembly in order to qualify the neutronic and photonic effects of the future JHR control rods. The final uncertainty on each measured wire lies below 1% (at 2 standard deviations). Experimental profiles are in a good agreement against Monte Carlo calculations, and the 4% capture rate increase at the plate edge is well observed. The flux asymmetry due to the assembly position in the core is also measured, and shows a 10% discrepancy between the two edges of the plate