Energetic Electron Spectra in Solar Energetic Particle Events Associated and Non-Associated to Coronal Mass Ejections

We considered energetic electron spectra in solar energetic particle (SEP) events after flare/coronal mass ejection (CME) associations and after flares only using measurements onboard various spacecraft (s/c) at radial distances of 0.3-1 AU during the 21st solar activity cycle. Statistics included about a hundred events of both types. More than 50 events of each type were observed simultaneously at various points of the inner heliosphere. Energy spectra in the range 0.3 to 3 MeV were generated from the maximum flux at each energy. The relationship between the exponent of integral electron spectrum, γ and CME speed, V and angular width was considered and it was obtained that electron spectra become harder with increase of V. The best correlation between DQG 9 arrives when the observer's magnetic footpoints are in the limits of the CME angular width. In this case the best fit approximation of γ(V) looks as γ∝V-0.5 with γ and V in the range of 4.5-1.5 and 500-2000 km/s, correspondingly.