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

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...

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Bibliographic Details
Main Authors: Pablo G. Ortega, Jorge Segovia, David R. Entem, Francisco Fernández
Format: Article
Language:English
Published: Elsevier 2018-03-01
Series:Physics Letters B
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0370269318300121
Description
Summary: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.
ISSN:0370-2693
1873-2445