In situ gamma spectroscopy of spent nuclear fuel using a CdTe detector

Gamma spectroscopy using a room temperature CdTe detector has been carried out in the proximity of a spent nuclear fuel rod. In this context, a compact and transportable monitor, incorporating a planar CdTe crystal was constructed and installed inside the β-γ hot cell. It provided effective shielding for the crystal against the intense background. Gamma spectra, with an energy resolution (FWHM) of 7.2 keV at 662 keV, were obtained in 600 s counting time, which would allow verification of the burnup to within 10% and cooling time of the fuel to within 3% of the declared values by applying specific isotopic correlations. The good spatial resolution has allowed the use of the monitor as a gamma scanning device.