  Using the observations from the Optical and Near-infrared Solar Eruption
Tracer and the Solar Dynamics Observatory, we study an M5.7 flare in AR 11476
on 2012 May 10 and a micro-flare in the quiet Sun on 2017 March 23. Before the
onset of each flare, there is a reverse S-shaped filament above the polarity
inversion line. Then the filaments become unstable and begin to rise. The
rising filaments gain the upper hand over the tension force of the dome-like
overlying loops and thus successfully erupt outward. The footpoints of the
reconnecting overlying loops successively brighten and are observed as two
flare ribbons, while the newly formed low-lying loops appear as the post-flare
loops. These eruptions are similar to the classical model of successful
filament eruptions associated with coronal mass ejections. However, the
erupting filaments in this study move along large-scale lines and eventually
reach the remote solar surface, i.e., no filament material is ejected into the
interplanetary space. Thus both the flares are confined ones. These results
reveal that some successful filament eruptions can trigger confined flares. Our
observations also imply that this kind of filament eruptions may be ubiquitous
on the Sun, from active regions with large flares to the quiet Sun with
micro-flares.
