Reactions ${}_{}{}^{16-18}{}_{}{}^{}\mathrm{O}$+${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$ and ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$+${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$ are studied at about 5 MeV/nucleon. ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$+${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$ reactions are studied also at lower energies. General features of energy spectra, the most probable $Q$ values, which show a large energy dissipation, and, in particular, angular distributions of projectilelike products are found to be very similar to those of deep inelastic collisions of heavier systems at much higher energies. All the angular distributions in $Q$-value intervals of 5 MeV, $\frac{d^2\sigma }{d\Omega \mathrm{dQ}}$, exhibit forward-peaking features and are well fitted by a form $A\frac{\exp (-\mu \theta )}{sin\theta }$. Systematics of the variation of $\mu$ vs $\mathrm{}\left|Q\right|\mathrm{}$ and the number of transferred nucleons, $n$, are discussed. A picture of the rotating dinucleus model is consistent with the present observations. Cross sections of isotope production have a simple relation with $Q_{\mathrm{gg}}$ including a nonpairing effect of the residual targetlike nucleus.

NUCLEAR REACTIONS ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}({}_{}{}^{16}{}_{}{}^{}\mathrm{O}, X)$, $E=88, 70, 60$ MeV, ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}({}_{}{}^{17}{}_{}{}^{}\mathrm{O}, X)$, $E=86.4\mathrm{}$ MeV, ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}({}_{}{}^{18}{}_{}{}^{}\mathrm{O}, X)$, $E=88\mathrm{}$ MeV, ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}({}_{}{}^{19}{}_{}{}^{}\mathrm{F}, X)$, $E=95\mathrm{}$ MeV, $Z=\mathrm{isotopes}\mathrm{of}\mathrm{elements}$ from $Z=2\mathrm{} \mathrm{to} Z$ (projectile), measured energy spectra, $\sigma$, $\sigma \left(\theta \right)$, and $\sigma (\theta , Q)$.

• Received 27 May 1982

DOI:https://doi.org/10.1103/PhysRevC.27.2621