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A recent report of $e^{+}{e}^{-}\to D\overline{D}$events by the BESIII collaboration suggests the presence of a structure $R$at 3900 MeV. We argue that this structure, called $G\left(3900\right)$in the past, is not in fact due to a new $c\overline{c}$resonance but rather naturally emerges due to a combination of interference between nearby resonances and the opening of the $D^{*}\overline{D}$channel. We further find that the appearance of this structure does not require suppression because of a radial node in the $\psi \left(4040\right)$wave function, although a node improves fit quality. The measured $e^{+}{e}^{-}$coupling of $\psi \left(4040\right)$is found to be substantially smaller than previously estimated. In addition, we report new corrections to the measured cross section $\sigma (e^{+}{e}^{-}\to D\overline{D})$at energies near $\psi \left(3770\right)$. Published by the American Physical Society2024 

Abstract Three-minute oscillations are a common phenomenon in the solar chromosphere above a sunspot. Oscillations can be affected by the energy release process related to solar flares. In this paper, we report on an enhanced oscillation in flare event SOL2012-07-05T21:42 with a period of around 3 minutes that occurred at the location of a flare ribbon at a sunspot umbral–penumbral boundary and was observed in both chromospheric and coronal passbands. An analysis of this oscillation was carried out using simultaneous ground-based observations from the Goode Solar Telescope at the Big Bear Solar Observatory and space-based observations from the Solar Dynamics Observatory. A frequency shift was observed before and after the flare, with the running penumbral wave that was present with a period of about 200 s before the flare coexisting with a strengthened oscillation with a period of 180 s at the same locations after the flare. We also found a phase difference between different passbands, with the oscillation occurring from high-temperature to low-temperature passbands. Theoretically, the change in frequency was strongly dependent on the variation of the inclination of the magnetic field and the chromospheric temperature. Following an analysis of the properties of the region, we found the frequency change was caused by a slight decrease of the magnetic inclination angle with respect to the local vertical. In addition, we suggest that the enhanced 3 minute oscillation was related to the additional heating, maybe due to the downflow, during the EUV late phase of the flare.