Energy flow and stopping in relativistic heavy-ion collisions atElab/A=14.6 GeV

Collisions of ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$+Al, Cu, Pb at ${\mathit{E}}_{\mathrm{lab}}$/A=14.6 GeV were studied in a calorimetry-based experiment at the BNL Alternating Gradient Synchrotron. Transverse-energy production was measured for pseudorapidities -0.5<η<0.8. Correlations with the spectra and multiplicity of neutrons and protons emitted into a forward 0.8° cone demonstrate quantitatively the large amount of nuclear stopping observed in these reactions. Calculations in hadronic-fireball or nucleon-nucleon based models underpredict the measured transverse-energy production for Si+Pb and indicate the need to include rescattering of secondaries and /or contributions from target fragmentation.