Proton energy deposition and material-dependent selectivity in ¹⁸ F-FDG production using a medical cyclotron PET trace 800

Energetic proton interactions with condensed matter constitute a non-equilibrium materials-physics problem governed by energy deposition and electronic excitation. In this work, proton energy deposition in an 18O-enriched aqueous target is examined from a condensed-matter perspective, emphasizing its role in material-dependent selectivity during fluorine-18 production using a medical cyclotron. Protons accelerated to 16.5 MeV induce the 18O(p,n)18F reaction while generating dense electronic excitation in the surrounding molecular environment. The results show that the spatial distribution of deposited energy and the condensed-phase structure of the target critically influence the effective formation and survival of 18F species, highlighting isotope production as a coupled proton–matter interaction rather than a purely nuclear process.