Book Description

Soft proton-antiproton interactions are selected from events collected with the CDF minimum-bias trigger at (square root)(s) = 1800 and 630 GeV. The analysis of their properties compared at the two energies reveals important and unexpected invariances. This paper describes an attempt to address the problem and the study of the properties of genuine soft interactions. These are identified as a subsample of proton antiproton interactions collected with the CDF minimum bias trigger. In the analysis a splitting procedure of the full minimum bias sample in two subsamples, one highly enriched in soft interactions and the other enriched in hard interactions, is applied. The two subsamples are analyzed separately through the compared measures of some inclusive distributions and final state correlations at different c.m.s. energies. The results evidence some interesting unobserved properties of the isolated soft sample and, in particular, a remarkably unpredicted invariance of some of the measured correlations and spectra between 630 and 1800 GeV.