Residues production in the $^{136}$Xe +p spallation reaction relevant for the incineration of nuclear waste
Résumé
The perspective of incineration of nuclear wastes in subcritical reactors (ADS) have triggered a dedicated long-range research program at GSI in order to reach a full comprehension of the protons and deuterons induced spallation reactions by measurements of evaporation and fission residues with the FRS spectrometer in inverse kinematics. One of the studied systems was 136Xe + p at different energies. Such system behavior remains similar to that of a lead system, found in ADS spallation target, while it can be studied at lower energies reached for the last. In this presentation, we will report on the results obtained on the spallation of 136Xe by protons at 500 A MeV and 200 A MeV, supplying experimental information in an energy range which contributes significantly to the spallation shower in a thick target geometry, and where the intra-nuclear cascade codes present more discrepancies with data. The main challenge of this experiment is related to the lower energy, because of the apparition of different atomic charge states that difficults the mass and charge identification. The measured cross sections of the isotopes produced in the 136Xe + 1H spallation reaction, their evolution with energy and their comparison with different intranuclear-cascade models and evaporation codes will be presented. An interesting feature is the even-odd staggering observed in the production cross sections of the heavy residues for Z=53, 54. This effect was better reproduced with a combination of the INCL4 intra-nuclear cascade and the statistical code ABLA, by introducing structural properties in the statistical decay of prefragments, as already developed in the case of the spallation of 238U + Ti at 1 A GeV