A new generalized activation chain compression method in NECP-X

The full-fidelity activation library is generally used for the activation photon source term calculation, but the memory requirement is unacceptable for the high-fidelity calculation. In order to minimize the memory requirement, a new generalized activation chain compression method is proposed. One basic compression element is a reaction channel or a decay path of an isotope, and the influence of every compression element to the final results are qualified. To enlarge the range of application of the new compressed library, an effective method to determine representative problems is developed and analyzed. Based on the ENDF-VII.0, EAF-2010 evaluated nuclear library and influence qualification-based activation library compression method, a new compressed activation library is generated. A set of problems are tested, including 2D VERA assembly problems, the VERA-3A problem and the KAIST problem, to assess the accuracy and the efficiency of the new activation library, showing its good accuracy and significant memory saving.