Possible large deuteronlike meson-meson states bound by pions

Using the analogy of the deuteron, spin-flavor symmetry, statistics, etc., it is argued that the one-pion exchange potential is likely to bind a few states composed of two ground-state mesons. The best S-wave candidates have masses, quantum numbers, and decay widths similar to those observed for the experimentally best established non-qq¯ candidates θ/${\mathit{f}}_0$(1720), G/${\mathit{f}}_0$(1590), ${\mathit{A}}_{\mathit{X}}$/${\mathit{f}}_2$(1520), and E/${\mathit{f}}_1$(1420). Possible P-wave states are the η(1410) and η(1490). Also the threshold enhancements seen in J/ψ→γρρ, γωω, γ${\mathit{K}}^{\mathrm{*}}$K¯ ${}_{}{}^{\mathrm{*}}{}_{}{}^{}$ and in γγ→ρρ are likely to be involved.