Observation of a Charged Charmoniumlike Structure in $e^{+}{e}^{-}\to D^0{D}^{-}{\pi }^{+}+c\mathrm{.}c\mathrm{.}$

We present a partial wave analysis of the process $e^{+}{e}^{-}\to D^0{D}^{-}{\pi }^{+}+c\mathrm{.}c\mathrm{.}$ using a data sample collected with the BESIII detector at a center-of-mass energy of 4682~MeV. A charged structure, referred to as the $X(3790{)}^{-}$ near the $D^0{D}^{-}$ mass threshold with a significance of $5.3\sigma$, which includes systematic uncertainties and the look-elsewhere effect. Assuming a Flatt'e description of the structure, the quantum numbers of the $X(3790{)}^{-}$ are found to be $J^P=1^{-}$, and its mass and coupling strength to the $D^0{D}^{-}$ channel are determined to be $(3794.7\pm 6.0\pm 8.7)$~MeV/$c^2$ and $(1.6\pm 0.2\pm 0.2)$~GeV, respectively, where the first uncertainties are statistical and the second systematic. In addition, we also report measurements of the masses and widths of the $D_2^{\ast }(2460)$, $D_1^{\ast }(2600)$, and $D_1^{\ast }(2760)$ charmed mesons.