Ericson fluctuations and the Bohr model in hadron physics

Analogies between the statistical bootstrap model for hadrons and the familiar statistical model for nuclei are pointed out, and used as a guide for suggesting new statistical treatments of hadron reactions: (i) the Fermi statistical model is modernized by including the full Hagedorn spectrum of resonances and brought into correspondence with the Bohr model by assuming that the reaction proceeds via an incoherent sum over direct-channel resonances; (ii) a definite prescription is given, predicting which hadron reactions should exhibit Ericson fluctuations; it is shown that the peaks and dips in pi N elastic scattering between p=1.5 and 5 GeV/c can be interpreted as Ericson fluctuations, although further experiments are needed to establish this interpretation definitively; (iii) the rapidly falling cross-sections found in exotic exchange reactions such as backward K /sup -/p to K/sup -/p are interpreted as the incoherent part of the sum over a Hagedorn spectrum of direct-channel resonances; especially large Ericson fluctuations are predicted for such cases. (53 refs).