Speaker
Description
The Particle Data Group (PDG) lists three scalar nonets, denoted $0^+_A, 0^+_B, 0^+_C$: one containing [$a_0(980), K_0^*(700)$], another containing [$a_0(1450), K_0^*(1430)$], and the third containing [$a_0(1710), K_0^*(1950)$]. We begin by noting that, within the tetraquark picture, two distinct color-spin structures are required to describe the tetraquark configurations of the [$a_0(980), K_0^*(700)$] and [$a_0(1450), K_0^*(1430)$] nonets. A notable challenge in understanding these states is the unexpectedly small mass difference between $a_0(1450)$ and $K_0^*(1430)$. In this work, we explore an additional mixing mechanism to address this puzzle, namely the $q\bar{q}$--tetraquark mixing, which may account for the [$a_0(1450), K_0^*(1430)$] and [$a_0(1710), K_0^*(1950)$] nonets [Reference: PRD 111, 054016 (2025)].
