Be9 States from the Reaction Li6(Li7, α)Be9

Abstract

${\mathrm{Li}}^6$ and ${\mathrm{Li}}^7$ ions accelerated to energies between 2.15 and 3.0 MeV were used to study the reaction ${\mathrm{Li}}^6({\mathrm{Li}}^7, \alpha ){\mathrm{Be}}^9$. Alpha particles were distinguished from other reaction products by a $\frac{\mathrm{dE}}{\mathrm{dX}}-E$ system based upon a general-purpose digital computer. States were observed at 0.00, 1.75, 2.43, 3.04, and 11.9 MeV excitation in ${\mathrm{Be}}^9$ in the presence of a very prominent continuum. The width of the 11.9±0.2-MeV state was measured at 500±100 keV. No other states up to an upper limit of 13.0-MeV excitation could be observed above the continuum. The yield of the 2.43-MeV state at 0° was found to have an energy dependence different from the ground and 3.04-MeV states. Angular distributions of the ground-state alpha particles obtained at ${\mathrm{Li}}^6$ bombarding energies of 2.2 and 3.0 MeV were observed to be slightly energy-dependent.