  The transverse momentum technique is used to analyse charged-particle
exclusive data in the central C-Ne and C-Cu interactions at a momentum of 4.5
Gev/c per nucleon.The results are presented in terms of the mean transverse
momentum per nucleon projected onto the estimated reaction plane <P_{x}(Y)> as
a function of the rapidity Y in the laboratory system. The observed dependence
shows the typical S-shape behaviour reflecting the presence of flow effects.
The value of flow F is obtained that increases with the atomic number of the
target. The Monte Carlo cascade Quark Gluon String Model (QGSM) is used for the
comparison with the experimental data. The QGSM reproduces the spectra and the
mean kinematical characteristics of the protons (<Y>....<N_{p}>) but
underestimates their transverse flow.
