A study of the quiescent filament eruptions associated with and without Solar Energetic Particle Events

Gopalswamy et al. (2015; 2016) reported on several halo coronal mass ejections (CMEs) associated with quiescent filament eruptions (FEs) originating outside active regions, yet causing large (>10 MeV proton intensity) solar energetic particle (SEP) events. All these CMEs had fast speeds (V > 900 km/s) and soft proton spectra (spectral index > 4) in the 10 - 100 MeV range. Although only one event had a metric type II burst, interplanetary type II bursts were observed in all events indicating that the shock formations occurred at larger distances from the Sun. In this study we investigated the difference between filament eruptions associated with SEP events and those without. For this purpose, we considered SOHO/LASCO CMEs that are fast (V ≥ 900 km/s) and wide (AW ≥ 120˚ degree) in the interval 2010 May to 2017 Dec associated with front-side quiescent FEs. We identified 10 CMEs associated with quiescent FEs, out of which 5 associated with SEPs and the remaining five were not. Interplanetary type II bursts were present in SEP-associated events while non-SEP events lacked type II association. We found that other properties such as speed and filament length were similar in the two populations. However, the CMEs were more massive and had greater kinetic energy in SEP-associated events. This supports the idea that CME-driven shock is the source of SEP events.