Storm time equatorial belt – an “image” of RC behavior

Abstract

During geomagnetic storms a well defined belt of trapped protons and ENAs (energetic neutral atoms) is observed around geomagnetic equator at low L‐values. Their source is RC (ring current) protons existing at larger L‐values. Through charge exchange with the geocorona RC protons become ENAs and if subjected to a new charge exchange become trapped protons. From low latitude particle observations at four different local times we follow; the RC injection region, the drift of RC‐particles through the evening/afternoon into the morning sector, the RC‐asymmetry and convection loss to the dayside during the storm initial and main phase, and its development into a symmetric RC in the recovery phase of the storm.