B11-Induced Single-Nucleon Transfer Reactions

Abstract

Single-nucleon transfer reactions induced by 115.9-MeV ${\mathrm{B}}^{11}$ ions incident on targets of ${\mathrm{C}}^{12}$, ${\mathrm{C}}^{13}$, ${\mathrm{N}}^{14}$, ${\mathrm{N}}^{15}$, ${\mathrm{O}}^{16}$, and ${\mathrm{Ne}}^{20}$ have been studied with the primary objectives of elucidating the reaction mechanism and investigating the utility of such reactions as spectroscopic probes. Reaction-product energy spectra from the (${\mathrm{B}}^{11}$, ${\mathrm{Be}}^{10}$) and (${\mathrm{B}}^{11}$, ${\mathrm{B}}^{10}$) transfer reactions were recorded simultaneously for each target using a $\frac{\mathrm{dE}}{\mathrm{dx}}$ and $E$ particle identification system which permitted isolation and study of individual residual states. All reactions exhibited highly selective population of residual states, consistent with a particularly simple reaction model involving the direct transfer of a nucleon to an unexcited target core. Evidence was adduced for a mechanism favoring the population of high-angular-momentum states of this configuration. For all targets, ratios of measured cross sections for neutron and proton transfer reactions leading to analog residual states were used to obtain the relative ${\mathrm{B}}^{10}$+$n$ and ${\mathrm{Be}}^{10}$+$p$ parentage of the ${\mathrm{B}}^{11}$ ground state on the assumption of charge independence throughout the reactions. Calculations based on available $p$-shell wave functions were found to be in good accord with the experimental results.