JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 70, APR. 1, 1965, P. 1627-1637. 22 REFS.
A sudden increase of the particle intensity and of the magnetic field strength on September 25, 1961, at 1731 UT was detected by the ion-electron detector and the magnetometer on board Explorer 12 outside the earth's magnetosphere. Comparison of the cyclotron radii of the trapped protons with the distance through which the satellite traveled showed the event to be temporal rather than spatial. Similarities between particle fluxes as well as between magnetic fields during the increase and within the outer belt make it probable that the increase represents an impulse-like extension of at least a part of the outer belt. A deduced lower limit on the outward radial velocity of the extension is 156 km/sec. Crude calculations show that either the proton density near the outer edge is less than 100 cm-3 or the temperature is greater than 15 ev.
Major Subject Terms: EXPLORER XII SATELLITE, MAGNETIC FIELD INTENSITY, MAGNETOSPHERE, PARTICLE FLUX, SATELLITE OBSERVATION
Minor Subject Terms: BELT, BOUNDARY, DENSITY, EXTENSION, FIELD, FLUX, IMPULSE, INCREASE, INTENSITY, MAGNETISM, OBSERVATION, OUTER, PARTICLE, PROTON, SATELLITE
CASI Accession Number: A6522600 ISSN