Effects of popcorn mechanisms in p + p and Pb + Pb collisions at CERN SPS energies within the HIJING code

We have investigated the influence of different baryon production mechanisms on the rapidity distributions (dn/dy) and transverse mass (m _T) spectra of π^±, k ^± and p ^± in p + p and Pb + Pb collisions at the CERN super proton synchrotron (SPS) energies by utilizing the heavy ion jet interaction generator (HIJING) code incorporated with a modern version of PYTHIA (version 6.4). Predictions are compared using the simple and advanced popcorn mechanisms, denoted as HIJING/SP and HIJING/AP, respectively, with different model parameters. It is found that HIJING/AP/set4 (that includes the suppression of first rank baryons) better describes the yields of π^±, k ^± and $\overline{p}$ in p + p interactions at SPS energies. We have also validated the HIJING/AP/set5 (that includes set4 and string tension with value of $k_{{\alpha }_{a\left(b\right)}}=1.64k_0$, where k ₀ = 1 GeV/fm is the default string tension) by reproducing the identified hadron rapidity distributions and m _T-spectra in both peripheral (33%–43%) and central (0%–5(7)%) Pb + Pb collisions at different SPS energies. (paper)