Study of (He3, d) and (He3, t) Reactions in Light Nuclei at 25 Mev

Abstract

Angular distributions for the ${\mathrm{Be}}^9({\mathrm{He}}^3, d){\mathrm{B}}^{10}$, ${\mathrm{Be}}^9({\mathrm{He}}^3, t){\mathrm{B}}^9$, ${\mathrm{C}}^{12}({\mathrm{He}}^3, d){\mathrm{N}}^{13}$, and ${\mathrm{Ca}}^{40}({\mathrm{He}}^3, d){\mathrm{Sc}}^{41}$ reactions were measured at 25 Mev and also at 21 Mev for the carbon reaction. It was found that the angular distributions were strongly peaked forward, exhibited diffraction-like structure, and were asymmetric about 90°. The minimal positions of the angular distributions could be fitted with spherical Bessel functions of the appropriate order $l$, the angular momentum transfer of the ingoing proton. This analysis resulted in the same interaction radius for various levels in each of these reactions. The best-fit interaction radius for each case was 6.17, 5.91, 6.23, and 7.29 fermis, respectively. The Butler stripping theory was also fitted to the angular distributions; however, the average decrease of the angular distributions did not agree with the predicted decrease except in one case. The reactions exhibited the general characteristics of a direct process and could be predicted qualitatively with the simple form of direct interaction theories. The experimental equipment and the method of data analysis, using computer codes, is described. The ground-state $Q$ values were measured for the ${\mathrm{Ca}}^{40}({\mathrm{He}}^3, d){\mathrm{Sc}}^{41}$, ${\mathrm{Ca}}^{40}(d, n){\mathrm{Sc}}^{41}$, and ${\mathrm{O}}^{16}({\mathrm{He}}^3, d){\mathrm{F}}^{17}$ reactions. $Q$ values for levels excited by the ${\mathrm{Ca}}^{40}({\mathrm{He}}^3, d){\mathrm{Sc}}^{41}$ reaction were also measured.