Hosted by: Jiangyong Jia

Clustering of nucleons at freezeout has been studied by a number of theoretical tools, including semiclassical (fluctons), hyperharmonics and, lately, direct Path Intergal Monte Carlo. It was found to be effective starting from four nucleons, with ``preclusters" feeding into multiple bound states decaying into channels with light nuclei d,t,He3 and affecting proton distribution (kurtosis). It was further found that even a minor increase of the range of nuclear forces increases clustering dramatically. Furthermore, if there exists the QCD critical point (CP) with large correlation length ξ, attraction due to binary forces becomes unrealistically large. The resolution of this paradox was found to be due to repulsive many-body forces near CP, overcoming the binary attraction and effectively suppressing clustering. We briefly discuss current experimental data and point out locations hinting at certain drop in clustering.