There exists a great deal of concrete evidence in favor of the exotic four-quark nature of light scalars. At the same time, the further expansion of the area of the q2q¯2 model validity for light scalars on ever new processes seems extremely interesting and important. We analyze the BESIII data on the decay J/ψ→γπ0π0 and show that the results of this high-statistics experiment can be interpreted in favor of the four-quark nature of light scalar mesons f0(980) and f0(500).
Achasov, N. N., Bennett, J. V., Kiselev, A. V., Kozyrev, E. A., & Shestakov, G. N. (2021). Evidence of the four-quark nature of f 0 (980) and f 0 (500). Physical Review D, 103(1), 014010. https://doi.org/10.1103/PhysRevD.103.014010