Speaker
Description
In recent years, an increasing number of exotic hadrons have been observed, many of which appear near scattering thresholds. In this work, we focus on near-threshold states in systems governed by both short-range and Coulomb interactions, and calculate the compositeness to quantify their internal structure. When the Bohr radius $a_B$ is larger than the magnitude of the effective range $|r_e|$, the universal behavior driven by the short-range interaction emerges before the Coulomb interaction becomes dominant. In this case, the compositeness increases near the threshold as a remnant of the short-range universality. On the other hand, if $a_B < |r_e|$, the compositeness does not increase even near the threshold, since the Coulomb interaction dominates and the system no longer exhibits universal behavior. As an application of this framework, we discuss the internal structure of exotic hadrons and nuclear systems.