# Strong LHCb evidence supporting the existence of the hidden-charm molecular pentaquarks

Chen, Rui (School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China) (Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China) (School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China) ; Sun, Zhi-Feng (School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China) (Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China) ; Liu, Xiang (School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China) (Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China) ; Zhu, Shi-Lin (School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China) (Collaborative Innovation Center of Quantum Matter, Beijing 100871, China) (Center of High Energy Physics, Peking University, Beijing 100871, China)

10 July 2019

Abstract: On 26 March 2019, at the Rencontres de Moriond QCD conference, the LHCb Collaboration reported the observation of three new pentaquarks, namely ${P}_{c}\left(4312\right)$, ${P}_{c}\left(4440\right)$, and ${P}_{c}\left(4457\right)$, which are consistent with the loosely bound molecular hidden-charm pentaquark states composed of an $S$-wave charmed baryon ${\Sigma }_{c}$ and an $S$-wave anticharmed meson ($\overline{D}$, ${\overline{D}}^{*}$). In this work, we present a direct calculation by the one-boson-exchange model and demonstrate explicitly that the ${P}_{c}\left(4312\right)$, ${P}_{c}\left(4440\right)$, and ${P}_{c}\left(4457\right)$ do correspond to the loosely bound ${\Sigma }_{c}\overline{D}$ with ($I=1/2$, ${J}^{P}=1/{2}^{-}$), ${\Sigma }_{c}{\overline{D}}^{*}$ with ($I=1/2$, ${J}^{P}=1/{2}^{-}$), and ${\Sigma }_{c}{\overline{D}}^{*}$ with ($I=1/2$, ${J}^{P}=3/{2}^{-}$), respectively.

Published in: Physical Review D 100 (2019)