A novel approach to proton-boron-11 fusion

Abstract

Proton-boron-11 (p-$^{11}$B) fusion is a highly attractive aneutronic pathway for clean energy production, offering abundant fuel, negligible neutron activation, and the potential for direct energy conversion of charged $\alpha$ particles. However, its practical implementation is severely hindered by the extremely high Coulomb barrier, necessitating ignition temperatures far beyond those of conventional deuterium-tritium reactions. In this work, we propose a novel approach to enhance the low-energy fusion cross-section by introducing a negative muon ($\mu$). Instead of relying on the thermal equilibrium formation of a muonic molecule, we investigate a kinetic scenario in which a muonic hydrogen atom (p$\mu$) is formed first and subsequently bombarded with a $^{11}$B nucleus. We quantitatively characterize the dynamic screening of the proton's Coulomb field by the tightly bound $\mu$ cloud, the resulting modified Coulomb potential substantially lowers the effective barrier at intermediate separations. We also evaluate the penetrability, reaction cross-section, and reactivity of the p$\mu$-$^{11}$B system, the results indicate that the inclusion of $\mu$ enhances the tunneling probability by several orders of magnitude at incident energies below 100~keV, thereby significantly reducing the threshold for the nuclear reaction. This mechanism offers a promising alternative perspective for catalyzing p-$^{11}$B fusion, and also suggests a potential ignition pathway.