The JO&Minna Framework: A Method to Interpret Depth Profiles of Activation

Abstract

A novel analytical framework, designated as the JO\&Minna method, is presented for interpreting the depth profiles of residual activation induced by heavy-ion beams in thick structural materials. By combining the limiting fragmentation and factorization principles, the JO-factor formalism rigorously links the spatial distribution of projectile-like fragments to the range derivatives and electronic stopping powers. Furthermore, the Minna procedure establishes a mathematical link via profile differentiation and convolution analysis to reconstruct the original energy spectrum and energy spread of the fragments from the measured activity profiles. The methodology is benchmarked using experimental data for $^{46}\text{Sc}$ production from $^{238}\text{U}$ irradiation in aluminum, demonstrating a reliable and straightforward approach for extracting fragment production kinematics and energy distributions in accelerator materials research.