The production of cosmic radiation by a solar flare on August 31, 1956

Abstract

It is shown that the neutron counting rates observed by three widely separated recorders increased by approximately two percent about half an hour after the observation of an intense solar flare at 1226 U.T. on August 31, 1956. The event, as observed at all three stations, exhibited the abrupt onset, and gradual recovery typical of solar flare effects. The time delay between the first visual sighting of the flare, and the earliest arrival of cosmic radiation at the earth was about 20 min. It is shown that the quantity of cosmic radiation which arrived at the earth was two to three orders of magnitude less than the quantities which arrived during earlier flare effects. Consideration of the temporal dependence of the small flare effect suggests that only a small quantity of cosmic radiation was produced in the solar flare.