  Multiparticle spike-production process is investigated in central C-Cu
collisions at 4.5 $A$ Gev/c per nucleon. The study is based on two different
hypotheses - stochastic vs. coherent - of the formation of spikes. To observe
manifestations of the stochastic dynamics, the non-regularities in the
multiplicity distributions are analyzed using intermittency approach to a
possible phase transition as well as the one-dimensional intermittency model.
The entropy indices are calculated based on the erraticity approach. Coherency
is studied in the framework of the coherent gluon-jet radiation model. To this
end, the spike-center pseudorapidity distributions are analyzed. Coexistence of
the two mechanisms of spike formation process is discussed.
