Fig. 1: (Anti)deuteron production scenarios.

Illustration of three scenarios for deuteron production and interaction with pions (left) and the resulting π^±–d correlation functions (right). All scenarios include Coulomb attraction between π⁻–d (green curves) and Coulomb repulsion between the π⁺–d (red curves). The dashed lines always show the correlation function using Coulomb interaction. a,b, Thermally produced deuterons with only Coulomb (a) and Coulomb + elastic + inelastic (b) interactions, respectively. c, Deuteron formation by nuclear binding following Δ-resonance decays. All the simulations include the charge conjugates (\({{\rm{\pi }}}^{+}-{\rm{d}}\equiv {{\rm{\pi }}}^{+}-{\rm{d}}\oplus {{\rm{\pi }}}^{-}-\overline{{\rm{d}}}\) and \({{\rm{\pi }}}^{-}-{\rm{d}}\equiv {{\rm{\pi }}}^{-}-{\rm{d}}\oplus {{\rm{\pi }}}^{+}-\overline{{\rm{d}}}\)). The bandwidths corresponds to the statistical uncertainties of the models.