Main results of a search on multiplicity distributions in pp collisions: is anybody afraid of a new class of hard events?

Abstract

After an introduction on possible scenarios in the TeV energy region in pp collisions, extrapolated from the knowledge of the GeV energy region, attention is focused on the onset of a third class of events, harder than the semi-hard and soft ones identified at SpS and Tevatron. The expected features and signatures in multiplicity fluctuations, forward-backward correlations and collision energy density are discussed.