On the Reaction F¹⁹(p, α)O¹⁶ in the Range of Bombarding Energy from 2.2- to 3.4-MeV

The reaction F 19 ( p , α 0 )O 16 was studied with the bombarding energies of a few MeV proton. Excitation curves were measured at 90° and 135° (1ab.) from 2.24- to 3.35-MeV with the energy step of about 20 KeV. The angular distributions were measured at twelve energies in the region between 2.64- and 3.35-MeV. Most of the angular distributions are asymmetric with respect to 90° (C. M.). The data were analyzed with the theory of fluctuation and the coherence energy \(\) was found to be 60 KeV, which corresponds to the lifetime of compound nucleus τ of 1.1×10 -20 sec.. The ratio of the direct reaction to the compound process, x D =σ D /<σ>, was found to be zero at 90° (1ab.) and 0.90 at 135° (1ab.) and also for the integrated cross section.