Alpha-particle condensation in nuclei: Experimental problems

Recently, it was supposed that n alpha light nuclei may have structures resembling the diluted gas of a particles which could be considered as Bose-Einstein condensate (alpha BEC) in nuclear systems. At the present time, the only more or less definite candidate for an aBEC state predicted by theory is the second 0(+) state of C-12 (E = 7.65 MeV) located near the threshold C-12 -> 3 alpha. We discuss several possible experimental approaches to study the properties of interest of the 7.65-MeV level of 12C. Among them are shift of the positions of the rainbow minima in the inelastic scattering to this level, extraction of the empirical inelastic form factor from the alpha and He-3 scattering and its comparison with theoretical predictions, and getting information on the Be-8 transfer reaction form factor. The conclusion was drawn that new measurements of C-12(alpha, alpha')C-12(7.65) inelastic scattering at similar to 120 MeV in the full angular range would be most adequate to solving the problem. The possibility of observation of alpha BEC effects in heavier na nuclei is also discussed. In particular, Ba-112 is of great interest owing to possible existence of an a-particle "halo" outside the Z = N = 50 core.