One of the particular interests at high-energy nucleus-nucleus collisions results from the expectations of the collective phenomena. It allows strong interactions in which nuclear matter undergoes a phase transition to quark-gluon plasma at very high temperature ~200 MeV or energy densities 〖~(2-3)ϵ〗_∘(1). The characteristic feature of this matter beyond the productions of excited baryonic and mesonic states is the individual nucleon-nucleon collisions. As a result, nucleons and hadrons are observed over a wide range of energies and angles (2). This paper presents the experimental properties of slow fragments (E≤400 MeV) which are produced from 28Si collisions with composite target emulsion nuclei at energy 14.6 A GeV per nucleon. The multiplicities of secondary slow particles are classified according to their emission angles θ, which are measured from direction of incident projectile. First, is forward hemisphere FHS, those are particles with lab< 90 and second backward hemisphere BHS with lab ≥ 90. It is important to study experimental features and search for the physical system responsible for production of these fragments. Experimentally, it’s possible to distinguish between projectile and target fragments where the projectile spectator fragments are mainly those emitted in a narrow cone where lab≤13 mrad at energy 14.6 A GeV (3-5) while target fragments essentially emitted in a wide range of angles as evaporated fragments from the residual nucleus and re-scattering or knock out protons and slow mesons. The dependences of the production of these particles and their multiplicities on the projectile mass numbers and energies are also investigated. |
