This paper search for the results and properties of slow particle productions, appear as a gray and black tracks in nuclear emulsions, producing secondary charged particles which are emitted from [Formula: see text]Si interactions with emulsion nuclei at 14.6[Formula: see text] GeV. The forward particles emission of interactions, ([Formula: see text]) as well as the backward ones ([Formula: see text]), have been investigated. It includes the effect of both projectile mass number and energy on the production and multiplicities of these particles. The results compared with other experiments for the same target but with different projectiles and energies. The experimental data show that there are two different mechanisms responsible for the production of gray particles for the chosen channels of emission angles and each are energy dependence. This dependence is weakly on the projectile mass number. The same investigations are applied for black tracks producing particles. The experimental results show the production of these particles is purely target fragments independent on both projectile mass number and its energy. The anisotropy ratio of angular distribution (F/B) is applied for both kinds of particles which are found the value for gray particle production depends on the direction of emissions while it is unchanged for black particles.