proton-Boron fusion in Plasma

The conventional route of nuclear fusion for power generation is based on the reaction between deuterium and tritium nuclei, which yields one α-particle and one neutron. Formidable technological challenges, however, stem from the production and handling of tritium, as well as from the radiation damage and induced radioactivity by high-energy neutrons in the reactor. To this respect, the nuclear reaction between a proton and a 11B nucleus (p-11B fusion) yielding three energetic α-particles is very attractive, as it only involves abundant and stable isotopes in the reactants and no neutrons in the reaction products. The three α-particles generated from p–11B fusion present a broad energy spectrum that peaks around 4 MeV; however, cutoff energies up to 10 MeV have been already demonstrated experimentally. In the last 15 years, p–11B fusion has been effectively induced by means of high-power lasers. In this case, an impressive progression in the reaction yield has been observed to the extent that the reaction has become of interest for the energy sector, where it is being considered as an alternative approach to conventional inertial confinement fusion schemes.The chance to optimize the p-11B reaction producing intense α-particles streams in a compact, and potentially economic, way opened the path for the realization of future table-top sources to be used in medical (i.e. radioisotopes production) and multidisciplinary applications.

However, nowadays, an extensive systematic investigation of laser-based p-11B fusion, to achieve a better and deeper understanding of the underpinning physics of the nuclear reaction in plasma, is still missing.

Parallel progress in target optimization, in order to maximize the reaction rate and, hence, the fluence of produced alphas, as well as in reaction products diagnostic, are also necessary.

The line of research of LNS-INFN aims to study and realize a new generation of solid targets, allowing for a more efficient in-plasma p-11B fusion reactions, to design and realize optimized detectors for the measure of the reaction products and to carry out a new class of in-plasma p-11B fusion experiments based on nanosecond and femtosecond high repetition rate laser system.