Mapping a new cluster of charmoniumlike structures at e+e− collisions

Abstract

In this work, we find a Critical Energy induced Enhancement (CEE) mechanism for the general three-body open-charm process at the e+e− collisions, which utilizes the peculiar kinematic behavior of the e+e− annihilation process involving three-body final states. We present a general analysis of a three-body process e+e−→BC→B(C→DE). When the center-of-mass (CM) energy of the e+e− collision satisfies a critical relation s=mB+mC, there clearly exists the reflection peak of an intermediate C state near the threshold of the invariant mass distribution of mBE or mBD, whose formation is very sensitive to the CM energy. The reflection enhancement phenomenon induced at the critical energy means that a new cluster of charmoniumlike structures can be experimentally mapped. Taking an example of e+e−→Ds⁎−Ds2⁎(2573)+→Ds⁎−(D0K+), we further illustrate this novel phenomenon when s=4.680 GeV. What is more important is that a series of optimal CM energy points to search for new charmoniumlike structures in three-body open-charm processes from e+e− annihilation are suggested, which can be accessible at BESIII and further BelleII as a new research topic.