Description
The proton-boron (pB) fusion reaction generates three alpha particles and releases 8.7 MeV of energy. It has been proposed as an alpha particle source for applications such as medical radioisotope production. However, radioisotopes of interest (e.g. $^{43}$Sc and $^{211}$At) require alpha particle energies in the range of 10-50 MeV to produce, which is significantly beyond the typical energy of the fusion-generated alpha particles. Using particle-in-cell (WarpX) simulations, we demonstrate the acceleration of boron ions via hole-boring radiation pressure acceleration in a near-critical density plasma. The laser/target conditions were tuned to maximise the boron flux between 1 and 10 MeV/u where the pB fusion cross-section is greatest. Driving pB fusion with boron ions enabled the generation of beamed alpha particles with energies up to 40 MeV, which are capable of producing the desired radioisotopes.
