Given an initial mass of some isotope subjected to a constant neutron flux, how fast will the mass drop off? Would not the survival curve look exactly like the curve for radioactive decay? Both cases describe a starting mass subjected to a constant transformative force at a rate that depends on the size of the population. The target mass shrinks in both cases, whether the cause is internal or external. Can’t the decay formula can be used for both? Does this concept have a name?