Additional evidence for the existence of the 12C nucleus as three α-particles and not as 8Besub(g.s.)+α

The probability |A|2 for the existence of the 12C nucleus as a 8Be nucleus in its ground state plus an α-particle has been calculated in PWBA by comparing the differential cross-sections of the stripping reactions (12C,8Be) and (8Be,α) for transitions between the same energy levels. The reactions 12C(12C,8Be)16O and 16O(α,8Be)12C, available in the literature and leading to the ground states of the final nuclei, have been considered normally for the first one and by reciprocity in the reverse direction for the second one in order to have identical targets and residual nuclei in both cases. The results have shown, as expected, that this probability |A|2 is very small which rejects the picture of the 12C nucleus as a 8Besub(g.s.) nucleus plus an α-particle and supports the 3α-particles structure for the 12C nucleus. (author)