Two-Proton Final-State Interactions in the ReactionsD(He3, t)2pandHe3(d, t)2pat a Center-of-Mass Energy of 21 MeV

Triton spectra were measured at 0 and 3° for the reaction $\mathrm{D}({}_{}{}^3{}_{}{}^{}\mathrm{He}, t)2p$ and at 5° for the reaction ${}_{}{}^3{}_{}{}^{}\mathrm{He}(d, t)2p$ at the same c.m. energy (21 MeV). The results were compared with predictions of the Watson-Migdal final-state interaction theory, and the proton-proton scattering length $a_p$ was determined for each reaction. Although the overall fit for the first reaction is poor, the best fit to the high-energy region of the data is obtained for $a_p=-12.6\mathrm{}\pm 0.6$ F. For the second reaction, $a_p=-7.3\mathrm{}\pm 0.6$ F gives a reasonably good overall fit.