Enhanced formation of a dense Kbar nuclear cluster K^- pp in pp collisions - Lambda*-p doorway dominance

We have found theoretically that the elementary process, p + p to K+ + Lambda(1405) + p, which occurs in a short impact parameter (around 0.2 fm) and with a large momentum transfer (Q ~ 1.6 GeV/c), leads to unusually large self-trapping of Lambda(1405) by the projectile proton, when a Lambda* -p system exists as a dense bound state (size ~ 1.0 fm) propagating to K^-pp. The seed, called "Lambda*-p doorway", is expected to play an important role in the (p, K*) type reactions and heavy-ion collisions to produce various Kbar nuclear clusters.