The subcritical polyethylene-reflected plutonium (PERP) metal fundamental physics benchmark. which is included in the Nuclear Energy Agency (NEA) International Criticality Safety Benchmark Evaluation Project (ICSBEP) Handbook. has been selected to serve as a paradigm illustrative reactor physics system for the application of the Second-Order Adjoint Sensitivity Analysis Methodology (2... https://www.earthtoyes.shop/product-category/pathfinders/