Centrality dependence of pion and proton spectra in C+C and C+Ta interactions at 4.2 GeV/cper nucleon

Analysis of rapidity spectra of negative pions ind + 12C,12C + Olimov1, Iqbal2, Glagolev3 et al. 2013Phys. Rev. C13000View full textAdd to dashboardCite

“…The procedure of the generation of a collision event in the QGSM consisted of three steps: (i) defining the configurations of the colliding nucleons, (ii) production of quark-gluon strings, and (iii) the breakup (fragmentation) of strings into observed hadrons. For simulating the nucleonnucleon and pion-nucleon interactions in the QGSM, the binary, "undeveloped" cylindrical, diffractive, cylindrical, and planar topological quark diagrams were used [21][22][23][24]. The binary processes give the main contribution to the QGSM and correspond to a quark rearrangement (in an interacting pair of nucleons) without direct particle emission in the string decay.…”

“…The 2-m propane bubble chamber was placed in a magnetic field of strength 1.5 T [22,[30][31][32][33][34][35][36]. Three tantalum 181 Ta foils also were placed in the experimental setup of the chamber.…”

“…The bubble chamber then was irradiated with beams of 2 H and 12 C nuclei accelerated to a momentum of 4.2 GeV/c per nucleon at the Dubna synchrophasotron. The deuterons and 12 C nuclei were made to interact with the carbon nuclei and protons of the propane molecules and the tantalum 181 Ta foils placed in the propane bubble chamber [22,[34][35][36]. Methods of selection of inelastic d + 12 C, 12 C + 12 C, and 12 C + 181 Ta collision events in this experiment were explained in detail in Refs.…”

“…Information about the state of excited or/and compressed nuclear matter created in relativistic nucleus-nucleus collisions, collision dynamics, and the particle production mechanism could be extracted from the analysis of the collision centrality dependence of the rapidity and transverse momentum spectra of pions [10,[22][23][24][25]. The momentum, transverse momentum, and rapidity distributions of negative pions produced in Mg + Mg collisions at 4.3 GeV/c per nucleon were analyzed in Ref.…”

“…The centrality dependence of the pion rapidity spectra in minimum bias 12 C + 12 C and 12 C + 181 Ta collisions at a momentum of 4.2 GeV/c per nucleon was partly studied in Ref. [22] on statistics of 7900 12 C + 12 C and 2000 12 C + 181 Ta inelastic collision events, which is less than half the total statistics of inelastic 12 C + 12 C and 12 C + 181 Ta collision events used in the present analysis. It was observed [22] that the pion rapidity spectrum resembled a Gaussian shape regardless of the target mass number and collision centrality and that the QGSM could reproduce the main features of pion rapidity as well as transverse momentum spectra quite well [22].…”