We report an observation of a partially erupting prominence and its associated dynamical plasma processes based on observations recorded by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory. The prominence first went through a slow rise (SR) phase followed by a fast rise (FR) phase. The SR phase began after a couple of small brightenings were seen toward the footpoints. When the prominence had transitioned from SR to FR, it had already become kinked. The prominence shows strong brightening at the central kink location during the start of FR. We interpret this as an internal magnetic reconnection occurring at a vertical current sheet forming between the two legs of the erupting prominence (flux rope). The brightening at the central kink location is seen in all EUV channels of AIA. The contributions of differential emission at higher temperatures are larger compared to that for typical coronal temperatures supporting a reconnection scenario at the central kink location. The plasma above the brightening location is ejected as a hot plasmoid-like structure embedded in a coronal mass ejection, and those below the brightening move down in the form of blobs moving toward the Sun's surface. The unique time resolution of the AIA has allowed these eruptive aspects, including SR-to-FR, kinking, central current sheet formation, plasmoid-like eruption, and filament "splitting," to be observed in a single event, providing strong and comprehensive evidence in favor of the model of partially erupting flux ropes.
