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Figure 1: Time profiles of protons and electrons in (a) gradual (proton) and in (b) impulsive (He-rich) events.

 
Figure 2: Longitude distributions of gradual and impulsive events.

 
Figure 3: Intensity profiles for protons of different energy for observers viewing a CME from the three different longitudes indicated in the panels.

Table 1. Properties of Impulsive and Gradual Events ------------------------------------------------------------ Impulsive Gradual ------------------------------------------------------------ Particles: Electron-rich Proton-rich He/He 1 0.0005 Fe/O 1 0.1 H/He 10 100 Q 20 14 Duration Hours Days Longitude Cone <30 deg 180 deg Radio Type III, V (II) II, IV X-rays Impulsive Gradual Coronagraph --- CME (96%) Solar Wind --- IP Shock Flares/year 1000 10 ------------------------------------------------------------