Examples of the yield function of ²⁶Al production in the lunar rock for different depths as denoted in the legend in units of cm²/g. Panel A corresponds to shallow layers of sample 64 455 in idealized conditions (infinite exposition age, no erosion). Panel B corresponds to the Apollo 15 long drill core. These yield functions are shown here for illustration, but for each case they were computed individually considering realistic exposition age, erosion rate, geometry, chemical composition, and measurement details (see Sect. 2.1).