$\alpha$ knockout reaction as a new probe for $\alpha$ formation in $\alpha$-decay nuclei

Abstract

The $\alpha$-decay phenomennon has been studied for more than a century but the mechanism of the $\alpha$ particle formation and its tunneling process have not yet been fully understood. As an alternative to the $\alpha$-decay lifetime measurement, we propose the proton-induced $\alpha$ knockout reaction, ($p$,$p\alpha$), as a new probe for the surface $\alpha$ formation probability of $\alpha$-decay nuclei. The ${}^{210,212}$Po($p$,$p\alpha$)${}^{206,208}$Pb reaction is described by the distorted-wave impulse approximation framework. It shows that the ${}^{212}$Po/${}^{210}$Po ratio of the $\alpha$ knockout cross sections agrees with that of the surface $\alpha$ formation probabilities determined by lifetime measurements. The result implies that the ($p$,$p\alpha$) cross section is a direct probe for the surface $\alpha$ formation probability, which is an essential quantity to lead us to a complete understanding of the $\alpha$-decay phenomenon.

5 pages, 5 figures

References in corpus (3)

• Neutron skin thickness of heavy nuclei with $\alpha$-particle correlations and the slope of the nuclear symmetry energy
• Unexpectedly enhanced $\alpha$-particle preformation in ${}^{48}$Ti probed by the $(p,p\alpha )$ reaction
• Direct probing of the cluster structure in ${}^{12}$Be via $\alpha$-knockout reaction

Cited by in corpus (4)

• Validation of the ${}^{10}\mathrm{Be}$ Ground-State Molecular Structure Using ${}^{10}\mathrm{Be}(p,p\alpha {)}^6\mathrm{He}$ Triple Differential Reaction Cross-Section Measurements
• The study of the alpha formation probability in 10Be and 12Be within the microscopic cluster model
• Significance of the refraction effect on the $p$-$d$ elementary process in the ($p$,$pd$) reaction
• Systematic analysis of the nuclear absorption effect on the cross section of the knockout reaction