Centrality dependence of the thermal excitation-energy deposition in 8–15 GeV/chadron-Au reactions

Abstract

The excitation energy per residue nucleon (${E}^{*}/A$) and fast and thermal light particle multiplicities are studied as a function of centrality defined as the number of grey tracks emitted ${N}_{\mathrm{grey}}$ and by the mean number of primary hadron-nucleon scatterings ($\ensuremath{\langle}\ensuremath{\nu}\ensuremath{\rangle}$) and the mean impact parameter ($\ensuremath{\langle}b\ensuremath{\rangle}$) extracted from it. The value of ${E}^{*}/A$ and the multiplicities show an increase with centrality for all systems, 14.6 GeV p-Au and 8.0 GeV \ensuremath{\pi}-Au and $\overline{\mathrm{p}}$-Au collisions, and the excitation energy per residue nucleon exhibits a uniform dependence on ${N}_{\mathrm{grey}}$.