Newly observed a0(1817) as the scaling point of constructing the scalar meson spectroscopy

Stimulated by the newly observed a(0)(1817) by the BESIII Collaboration, we find a perfect Regge trajectory composed of the a(0)(980), a(0)(1450), and a(0)(1817), which leads us to categorize the a(0)(980), a(0)(1450), and a(0)(1817) into the isovector scalar meson family. This scenario is supported by their two-body Okubo-Zweig-lizuka allowed strong decay behaviors. In this scheme, we also predict the third radial excitation of the a(0)(980), which is denoted as the a(0)(2115), accessible at future experiment as a direct test of this assignment. We find another Regge trajectory which contains three isoscalar scalar states f(0)(980), X(1812), and f(0)(2100). We investigate their two-body Okubo-Zweig-Iizuka allowed strong decay patterns, which arc roughly consistent with the experimental data. The f(0)(980), X(1812), and f(0)(2100) can be well grouped into the isoscalar scalar meson family. We want to emphasize that these two Regge trajectories have a similar slope. In summary, the present work provides a scheme of constructing the scalar meson family based on these reported scalar states. The possibility of the f(0)(1710) as the candidate of the scalar glueball cannot be excluded by the observation of the a(0)(1817) since the a(0)(1817) is more suitable as the isovector partner of the X(1812).

Automated summary

Stimulated by the newly observed a(0)(1817) by the BESIII Collaboration, this study proposes a scheme for constructing the scalar meson family based on observed scalar states. Two Regge trajectories are identified and the third radial excitation is predicted. The study has important implications for understanding the properties of scalar mesons.