The Reaction Energies of Light Nuclei from Magnetic Analysis

An extensive survey has been made of the reaction energies of ground-state transitions induced by proton and deuteron bombardment of light nuclei. A total of nineteen stable nuclei from deuterium through sulfur was investigated, and the $Q$-values directly measured for thirty-eight different reactions. From these $Q$-values, the energy releases of a number of other reactions have been computed. The reactions studied include the $p,\alpha$, $d,p$, and $d,\alpha$; and the individual $Q$-values have been determined to precisions that are between 0.08 and 0.25 percent. The reaction products were analyzed by means of 180-degree focusing in the field of a large annular magnet. The $Q$-values measured include those of a series of nuclear reactions which directly connect the mass of the alpha-particle with the deuteron mass and ${\mathrm{O}}^{16}$. From these measurements, the mass of the alpha-particle has been determined as 4.003865±0.000007 amu.