Thermal cross sections of hydrogels for NMR-driven neutron capture therapy

We propose a neutron experiment to establish and validate a quantitative procedure whereby information from nuclear magnetic resonance (NMR) spectroscopy and imaging is used to provide patient-specific neutron scattering libraries to be used to optimize transport codes in neutron capture therapy. In particular, using chemical shift spectra from 1H-NMR, the idea is to reconstruct the relative concentrations of organic functional groups in standard samples, and use these data to build the sample-specific macroscopic cross section at thermal neutron energies using the Average Functional Group Approximation. Therefore, we propose a neutron transmission measurement, taking advantage of the broad range of incident neutron energies available on the VESUVIO spectrometer, on a series of well-characterized hydrogel systems composed of semi-interpenetrated polymer networks (SIPN) to be suggested and used as standards for both neutron scattering and NMR standards.