Multi-muon events deep underground and ultra-high-energy collisions

Abstract
The configurations of multi-muon events have been investigated in detail by a three-dimensional Monte-Carlo simulation, including recent features of high-energy collisions observed in a p-p collider. The average properties and topology of individual multi-muon events at depths 1800, 4200 and 5000 mWe underground are studied. Some criteria are suggested to identify average primary mass composition. The important link between multi-muon events and high multiplicity fluctuations or more copious multi-particle production in the energy range 106-107 GeV has been pointed out.