Study of excited states of O14 by a particle-particle angular-correlation technique

Abstract

Excited states of O14 have been investigated with the C12(He3, n)O14(p)N13 reaction at an incident-beam energy of 12 MeV. Proton groups corresponding to O14 excited states were observed in time coincidence with the associated neutrons detected at θn=0°. The natural widths of these states (or limits thereof) were obtained directly from the proton spectrum. Angular-correlation data obtained for these proton groups were analyzed according to a general formalism which allows channel spin as well as orbital angular momentum mixing in the O14→N13+p exit channel. These analyses yield the following spin and width limitations: [Ex (MeV), J, Γ (keV)]; 5.91, 0 or 1, ≤47; 6.29, 2 or 3, 103±6; 6.59, 2, ≤56; and 7.78, 1, 2 or 3, 76±10. The apparent dominance of a direct-transfer mechanism for the population of these states permits further spin and parity restrictions. Information regarding the wave-function configurations for these states is discussed on the basis of the observed proton decay. Of particular interest is the observance of an f-wave component in the proton decay of the 6.59-MeV state which implies an s4p8 (p, f) component in the wave function of that state. © 1973 The American Physical Society.