Pre-equilibrium <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>α</mi></math> Decay in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">O</mi></mrow><mprescripts></mprescripts><mrow></mrow><mrow><mn>16</mn></mrow><mrow></mrow><mrow></mrow></mmultiscripts></mrow></math> + <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">Al</mi></mrow><mprescripts></mprescripts><mrow></mrow><mrow><mn>27</mn></mrow><mrow></mrow><mrow></mrow></mmultiscripts></mrow></math> Collisions at 65 MeV

J. W. Harris; T. M. Cormier; D. F. Geesaman; L. L. Lee, Jr; R. L. McGrath; J. P. Wurm

doi:10.1103/PhysRevLett.38.1460

Pre-equilibrium $α$ Decay in ${}^{16}O$ + ${}^{27}{Al}$ Collisions at 65 MeV

J. W. Harris, T. M. Cormier, D. F. Geesaman, L. L. Lee, Jr., R. L. McGrath, and J. P. Wurm

Phys. Rev. Lett. 38, 1460 – Published 20 June 1977

Abstract

The mechanism of the reaction ${}^{27}{Al} ({}^{16}O, {}^{12}C α) {}^{27}{Al}$ at 65.6-MeV incident energy has been examined with use of coincidence techniques. It is shown that the broad bell-shaped peak observed in ${}^{12}C$ singles spectra corresponds to an $α$ -transfer-like process leading to fixed excitation energy in the $α$ + ${}^{27}{Al}$ system. The $α$ - ${}^{12}C$ angular correlation, however, is forward-peaked along the momentum-transfer direction, suggesting that the decay time of the system is less than required for equilibration into ${}^{31}P$ .