${\chi }_{c1}$ and ${\chi }_{c2}$ resonance parameters with the decays ${\chi }_{c1,c2}\to J/\psi {\mu }^{+}{\mu }^{-}$

LHCb collaboration, R. Aaij, B. Adeva +797

The decays ${\chi }_{c1}\to J/\psi {\mu }^{+}{\mu }^{-}$ and ${\chi }_{c2}\to J/\psi {\mu }^{+}{\mu }^{-}$ are observed and used to study the resonance parameters of the ${\chi }_{c1}$ and ${\chi }_{c2}$ mesons. The mass…