https://phys.org/news/2018-06-chances-clumps-atomic-nuclei.html

The lowering of energy in physical systems favours the merging of structures into groups. This powerful, universal mechanism occurs in nature on all size scales: quarks combine into mesons or baryons, atoms into molecules, stars into galaxies, and galaxies into groups of galaxies. In the case of atomic nuclei, computer simulations suggest that, e.g., the nucleus of beryllium 9Be contains two alpha clusters and one neutron (the whole complex would look like a dumbbell). In the 12C carbon nucleus, there should be three alpha clusters (the shape of the nucleus would thus be triangular), four in oxygen 16O (here the nucleus would resemble a pyramid), 10 in calcium 40Ca and 14 in nickel 56Ni.

In 2014, scientists from the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Cracow, in collaboration with physicists from the Universidad de Grenada, presented a method of detecting traces of the original structure of atomic nuclei in the distribution of velocities of particles diverging from the points of ultrarelativistic collisions of light atomic nuclei with a shield made of heavy nuclei, such as lead 208Pb lead or gold 197Au. Those predictions focused on methods of detection of alpha clusters in 12C carbon nuclei.