Multisatellite observations of MeV ion injections during storms

We report here on the formation of new ion radiation belts observed in connection with several solar energetic particle events and large geomagnetic storms in 1998 and 2000. We use observations from the Polar spacecraft, the highly elliptical orbit (HEO) 1997‐068, and the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX), to study details of the inner zone radiation belt at high and low altitudes. We focus specifically on the four International Solar Terrestrial Physics events of August and September 1998 and April and July 2000. In several events we find new 2–15 MeV proton belts at various locations between L = 2.0 and L = 3.5. The low‐altitude SAMPEX observations revealed features not visible at high altitudes, such as radiation belts with multiple peaks in L shell. During the July 2000 event, energetic helium and iron were observed at L ∼ 2, suggesting a solar energetic particle source for these injected ions. We compare observations of these new belts and remark on the significant differences from event to event.