Determination of spin and parity of the $Z_c(3900)$

Abstract

The spin and parity of the $Z_c(3900{)}^{\pm }$ state are determined to be $J^P=1^{+}$ with a statistical significance larger than $7\sigma$ over other quantum numbers in a partial wave analysis of the process $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}J/\psi$. We use a data sample of 1.92 fb${}^{-1}$ accumulated at $\sqrt{s}=4.23$ and 4.26 GeV with the BESIII experiment. When parameterizing the $Z_c(3900{)}^{\pm }$ with a Flatte-like formula, we determine its pole mass $M_{\text{pole}}=(3881.2\pm 4.2_{\text{stat}}\pm 52.7_{\text{syst}})\text{MeV}/c^2$ and pole width ${\Gamma }_{\text{pole}}=(51.8\pm 4.6_{\text{stat}}\pm 36.0_{\text{syst}})\text{MeV}$. We also measure cross sections for the process $e^{+}{e}^{-}\to Z_c(3900{)}^{+}{\pi }^{-}+c.c.\to J/\psi {\pi }^{+}{\pi }^{-}$ and determine an upper limit at the 90\% confidence level for the process $e^{+}{e}^{-}\to Z_c(4020{)}^{+}{\pi }^{-}+c.c.\to J/\psi {\pi }^{+}{\pi }^{-}$.

8 pages, 2 figures, 1 table

References in corpus (4)

• Charmonium
• Precise measurement of the $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}J/\psi$ cross section at center-of-mass energies from 3.77 to 4.60 GeV
• Four-Quark Hadrons: an Updated Review
• Covariant Helicity-Coupling Amplitudes: A New Formulation

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