High-latitude day side electric field and particle measurements

Two rockets carrying electric field and low energy particle instrumentation were launched near noon at 80 magnetic latitude. One flight encountered polar cap conditions only while the other traversed part of the polar cusp. Although weak particle precipitation was measured on both flights, bursts of intense magnetosheath-type electron fluxes were detected on the latter. Strong electric fields such as would result from anti-sunward convection were observed during both flights. The measurements are compared with results obtained by other types of spacecraft and interpreted in the light of those data.