Observation of Lifetime Effects in Two-Proton Correlations for Well-Characterized Sources

Differences between longitudinal and transverse two-proton correlation functions, consistent with finite lifetime effects, are observed for central Ar36+45Sc collisions at E/A=80 MeV. The correlations between two protons emitted with low total momenta are consistent with emission from a source of Gaussian radius r0≊4.7±0.3 fm and characteristic lifetime τ≊25±15 fm/c