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Communications Physics: A multi-MeV alpha particle source via proton-boron fusion driven by a 10-GW tabletop laser

A multi-MeV alpha particle source via proton-boron fusion driven by a 10-GW tabletop laser

Nuclear fusion supplies the stars with the required energy to generate light. Conventional fusion approaches in the laboratory utilize mostly deuterium-tritium reactions occurring in a hot plasma (yielding one alpha particle and one neutron), as this scheme requires relatively low temperatures. However, complementary fusion schemes are potentially very attractive in various contexts. For example, the fusion reaction between a proton and the Boron-11 isotope gives off three alpha particles and involves only abundant and stable isotopes in the reactants. Moreover, this reaction is aneutronic, i.e. the reaction products contain almost no neutrons, strongly reducing unwanted effects such as radiation damage and activation of surrounding materials. The high yield of alpha particles produced during the reaction is alluring not only for potential controlled fusion energy generation (advantageous electricity conversion) but also for multidisciplinary applications due to their useful energy range of several MeV, for example, the production of medical isotopes.

Our proof-of-principle experiment has demonstrated the possibility of using a compact commercial moderate-power laser and a special H-B target to trigger the pB fusion reaction at a high-repetition-rate operating regime, providing a continuous flux of energetic alpha particles. Such an approach is expected to pave the way toward future applications of multi-MeV alpha particles produced from pB fusion reactions triggered by tabletop high-repetition-rate lasers”, says Valeria Istokskaia, one of the ELI Beamlines doctoral candidates who conducted the experiment at the HiLASE facility. “We have shown how an original idea can be implemented through an intensive collaboration among international partners with complementary expertise, also thanks to the transnational access opportunities provided by the Laserlab Europe Consortium initiative”, adds Daniele Margarone, Director of Research and Operations at ELI Beamlines, who was leading this research during his academic experience as Lecturer at Queen’s University Belfast.

The scientific article was published in Communications Physics, an open access journal from Nature Portfolio: