Abstract: A method for analysing at least one fuel rod comprising a stack of nuclear fuel, a rod comprising packed zones completely filled with fuel and intermediate zones partially full of fuel, comprises: acquiring a count profile associated with a non-migrating isotope, a profile being made up of spectrometry measurements taken along the rod for this isotope; determining a set of at least one indicator K_i that makes it possible to quantify the reduction in material at an intermediate zone of index i, the said indicator being deduced from the count profile; detecting the change in geometry by comparing the set of at least one indicator K_i against a set of at least one reference value RK indicative of the initial geometry of the nuclear fuel stack.

Abstract: A method for analysing the effect of temperature on at least one nuclear fuel rod, a rod comprising packed zones completely filled with fuel and intermediate zones partially filled with fuel, comprises: acquiring at least two count profiles, a first count profile being associated with a non-migrating isotope and a second count profile being associated with a migrating isotope; locating the intermediate zones by using the first count profile; determining an indicator Ki_1 indicative of the depth in the first profile of a measurement dip located at an intermediate zone i; determining an indicator Ki_2 indicative of the depth in the second profile of a measurement dip located at the intermediate zone i; determining for this intermediate zone i an indicator ?i by comparing the indicators Ki_1 and Ki_2.

Abstract: A method for analysing at least one fuel rod comprising a stack of nuclear fuel, a rod comprising packed zones completely filled with fuel and intermediate zones partially full of fuel, comprises: acquiring a count profile associated with a non-migrating isotope, a profile being made up of spectrometry measurements taken along the rod for this isotope; determining a set of at least one indicator K_i that makes it possible to quantify the reduction in material at an intermediate zone of index i, the said indicator being deduced from the count profile; detecting the change in geometry by comparing the set of at least one indicator K_i against a set of at least one reference value RK indicative of the initial geometry of the nuclear fuel stack.

Abstract: A method for analysing the effect of temperature on at least one nuclear fuel rod, a rod comprising packed zones completely filled with fuel and intermediate zones partially filled with fuel, comprises: acquiring at least two count profiles, a first count profile being associated with a non-migrating isotope and a second count profile being associated with a migrating isotope; locating the intermediate zones by using the first count profile; determining an indicator Ki_1 indicative of the depth in the first profile of a measurement dip located at an intermediate zone i; determining an indicator Ki_2 indicative of the depth in the second profile of a measurement dip located at the intermediate zone i; determining for this intermediate zone i an indicator ?i by comparing the indicators Ki_1 and Ki_2.