2025/11/17 by Ampuku, Shota, Yamaguchi, Yasuhiro, Harada, Masayasu
#FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Nuclear Theory (nucl-th)
paper · doi:10.48550/arxiv.2511.13003
A central question in exotic-hadron physics is their internal structure whether these states are loosely bound hadronic molecules or compact multiquark configurations. To shed light on this issue, we develop a model that incorporates mixing between hadronic-molecular and compact multiquark components. We then apply this framework to the specific case of the Tcc(3875)+ and analyze the peak structure in the D0D0π+ invariant-mass spectrum reported by LHCb. We find that a scenario based on a predominantly compact tetraquark provides the best fitted solution which can explain the Tcc(3875)+. We also find that the model admits two more solutions of comparable quality, both of which imply that the Tcc(3875)+ is a molecular state: (1) the Tcc(3875)+ is a D*+D0 molecule and there is a D*0D+ molecular state in addition; (2) the Tcc(3875)+ is a D*0D+ molecule and an aditional D*+D0 molecular state is found below D0D0π+ threshold. These molecular states are not simple I = 0 states, but mixtures of I = 0 and I = 1 states. We show that all three scenarios are also consistent with the experimentally observed near-threshold D0D0 and D0D+ invariant-mass distributions.