Proton–boron fusion in femtosecond-laser-irradiated nanowire array target

In this work, we performed an experimental campaign to study α-particles from laser-driven proton–boron fusion on nanowire array targets. An ultra-intense laser was utilized with an intensity of 2×1020 W/cm2 to interact with nanowire array targets. We verified that nanowire targets have a stronger capability to generate nuclear reactions compared to flat targets. To reduce the sensitivity of the proton detection of CR-39 and improve the accuracy of the α-particle measurements, a Potassium–Ethanol–Water solution was used to treat the CR-39 detector. A yield of 3.3×106α/J was recorded from p–B fusion, consistent with the theoretical prediction. Moreover, in simulation predictions, we observe a rapid increase α-particle yield with laser pulse energy. Our investigation of fusion in nanowire array targets contributes to the understanding of fusion driven by nanostructured arrays, which potentially contribute to an intense α source as well as the fusion cross section study in plasma.