Search for JPC 1⁄4 1−þ exotic state in eþe− annihilation

The P-wave and S-wave heavy-light mesons and their charge conjugates, i.e., D1ð2420ÞD̄þ c:c:, D1ð2420ÞD̄ þ c:c:, and D2ð2460ÞD̄ þ c:c:, can couple to states with vector quantum number JPC 1⁄4 1−− and exotic quantum number JPC 1⁄4 1−þ in a relative S wave. Near threshold, the heavy-light meson pair may form hadronic molecules due to the strong S-wave coupling, and the mysterious vector state Yð4260Þ could be such a state of the D1ð2420ÞD̄þ c:c: molecule. This implies the possible existence of its conjugate partner made of the same heavy-light mesons but with exotic quantum number JPC 1⁄4 1−þ. We evaluate the production rate of such exotic hadronic molecules and propose a direct experimental search for them in eþe− annihilation. Confirmation of such exotic states in experiment will certainly deepen our insights into strong QCD and the arrangement of multiquark degrees of freedom.