Charmonium resonances in the 3.9 GeV/c2 energy region and the X(3915)/X(3930) puzzle

Physics Letters B

Pablo G. Ortega¹  David R. Entem¹  Francisco Fernández¹  Jorge Segovia² 

[1] Grupo de Física Nuclear and Instituto Universitario de Física Fundamental y Matemáticas (IUFFyM), Universidad de Salamanca, E-37008 Salamanca, Spain;Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany;

关键词: Potential models;    Charmed mesons;    Exotic mesons;   

DOI  :  10.1016/j.physletb.2018.01.005

来源: DOAJ

【 摘 要 】

An interesting controversy has emerged challenging the widely accepted nature of the X(3915) and the X(3930) resonances, which had initially been assigned to the χc0(2P) and χc2(2P) cc¯ states, respectively. To unveil their inner structure, the properties of the JPC=0++ and JPC=2++ charmonium states in the energy region of these resonances are analyzed in the framework of a constituent quark model. Together with the bare qq¯ states, threshold effects due to the opening of nearby meson–meson channels are included in a coupled-channels scheme calculation. We find that the structure of both states is dominantly molecular with a probability of bare qq¯ states lower than 45%. Our results favor the hypothesis that X(3915) and X(3930) resonances arise as different decay mechanisms of the same JPC=2++ state. Moreover we find an explanation for the recently discovered M=3860MeV/c2 as a JPC=0++ 2P state and rediscover the lost Y(3940) as an additional state in the JPC=0++ family.

【 授权许可】

Unknown