Measurement core for measuring nuclear heating in a nuclear reactor and calorimetric sensor incorporating such a measurement core

A measurement core for measuring nuclear heating in a nuclear reactor, said core extending in a longitudinal direction (X) and having a main plane (XY), said measurement core comprising at least:

• a first sample formed by a first layer of material, the first sample being an element of material of known weight for which the nuclear heating is sought to be measured;
• a first thin layer of electrical insulation disposed on the first sample;
• a thin conductive layer forming a heating electrical resistor disposed on the first thin layer of electrical insulation;
• and
• a second thin layer of electrical insulation disposed on the heating electrical resistor;
• the first thin layer of electrical insulation having dimensions in the main plane matched to those of the first sample;
• the thin layers of electrical insulation being configured to insulate the heating electrical resistor from the first sample and protect said heating electrical resistor;
• and
• the first sample having dimensions less than or equal to around fifteen millimetres in the main plane, and/or a thickness less than or equal to 10 millimetres.