Interpretation of pile-oscillation measurements by the integral data assimilation technique

The Integral Data Assimilation (IDA) was designed to deduce values of infinite dilute neutron cross-sections from specific integral measurements. Performances of the IDA procedure are demonstrated with pile-oscillation measurements carried out on 155Gd in the pool type reactor MINERVE (CEA Cadarache, France). At low neutron energies, the Integral Data Assimilation is based on the Neutron Resonance Shape Analysis technique routinely used in neutron spectroscopy measurements. As a result of the IDA analysis, a value of (61 900±1500) b has been obtained for the 155Gd thermal capture cross-section at (Eth=25.3 meV).