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Using about 23 $\mathrm{fb^{-1}}$ of data collected with the BESIII detectoroperating at the BEPCII storage ring, a precise measurement of the $e^{+}e^{-}\rightarrow \pi^{+}\pi^{-}J/\psi$ Born cross section is performed atcenter-of-mass energies from 3.7730 to 4.7008 GeV. Two structures, identifiedas the $Y(4220)$ and the $Y(4320)$ states, are observed in the energy-dependentcross section with a significance larger than $10\sigma$. The masses and widthsof the two structures are determined to be ($M, \Gamma$) =($4221.4\pm1.5\pm2.0$ MeV/$c^{2}$, $41.8\pm2.9\pm2.7$ MeV) and ($M, \Gamma$) =($4298\pm12\pm26$ MeV/$c^{2}$, $127\pm17\pm10$ MeV), respectively. A smallenhancement around 4.5 GeV with a significance about $3\sigma$, compatible withthe $\psi(4415)$, might also indicate the presence of an additional resonancein the spectrum. The inclusion of this additional contribution in the fit tothe cross section affects the resonance parameters of the $Y(4320)$ state.

Study of the resonance structures in $e^{+}e^{-} \rightarrow \pi^{+}\pi^{-}J/\psi$ process