A Two-satellite study of low-energy protons over the polar cap during the event of November 18, 1968

A study of low-energy solar proton intensity profiles over the northern polar cap has been made for the November 18 event. Use of data from two satellites crossing the polar cap at closely related universal times has permitted separation of spatial and temporal variations in the intensity profiles early in the event. The resulting spatial profiles have been related to the structure and length of the magnetotail and have been considered in terms of current theories of formation of the magnetotail.