Figure 1

Left:Invariant mass distribution of Λπ pairs for Σ(1385)+ after subtraction of the mixed-event background in 0–10% central Pb–Pb collisions and 3.5 < pT < 4.5 GeV/c. Right:Invariant mass distribution of Λπ pairs for Σ(1385)− after subtraction of the mixed-event background in 30–50% centrality class and 2.5 < pT < 3.5 GeV/c. The black curves represent the combined fit using a signal (continuous blue line) plus residual background (red dashed line) model, as described in the text.