Investigation of $\Delta^{0}$ and $\Delta^{++}$ isobar production in central $p^{12}\mathrm{C}$ and $d^{12}\mathrm{C}$ collisions at 4.2 $A$ GeV/$c$

Abstract

In this paper, we present experimental data on various characteristics of $\Delta^{0}$ and $\Delta^{++}$ isobars produced in central $p^{12}\mathrm{C}$ and $d^{12}\mathrm{C}$ collisions at a beam momentum of 4.2~A~GeV/$c$. The collision centrality is defined by the number of participating protons formed in the events under study. Experimental values of the mean multiplicity of participating protons are determined for both types of collisions. It is shown that, for $p^{12}\mathrm{C}$ and $d^{12}\mathrm{C}$ interactions, the effective masses and the widths of the mass spectra of the $\Delta^{0}$ and $\Delta^{++}$ isobars coincide within experimental uncertainties. Furthermore, the average multiplicities of $\Delta^{0}$ isobars are found to be larger than those of $\Delta^{++}$ isobars for both collision systems considered.