Electrons in the Earth's outer radiation zone

Journal Article · Thu Nov 01 04:00:00 EST 1962 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/JZ067i012p04533· OSTI ID:4740398

Rosser, W. G. V.; O'Brien, B. J.; Van Allen, J. A.; Frank, L. A.; Laughlin, C. D.

Preliminary results from Explorer 12 during August and September 1961 show that near the geomagnetic equatorial plane the omnidirectional intensity of 40-55 kev electrons is usually constant to a factor of 2 or 3 between radial distances of 25,000 and about 55,000 km; then it diminishes rapidly near the termination of the earth's magnetic field, which is generally at about 65,000 km. Typical midzone values for electrons between 40 and 55 kev are 10⁶ to 10⁷ electrons (cm² sec)^-1. The intensity of 80- to 100-kev electrons shows a similar radial dependence and a similar absolute value, but diminishes toward zero at a lesser radial distance. Hence the outer fringe of the outer zone at about 10 earth radii has a much steeper electron spectrum than the inner portion. The general structure of the outer zone as measured with a 302 Geiger tube by the staff members of this laboratory and other laboratories during the past four years is confirmed but is now shown to correspond to electrons of energy greater than 1.6 Mev in intensities of 10³ to 10⁵ (cm² sec)^-1 in the heart of the zone. Important spectral changes accompany geomagnetic storms.

• Research Organization: Iowa State Univ., Iowa City
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-005183
• OSTI ID: 4740398
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: 12 Vol. 67; ISSN 0148-0227
• Publisher: American Geophysical Union
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COSMIC RADIATION
DISTRIBUTION
EARTH
ELECTRONS
ENERGY
ENERGY RANGE
EXPLORER SATELLITES
GEIGER-MUELLER COUNTERS
KEV RANGE
LEVELS
MAGNETIC FIELDS
MEASURED VALUES
MEV RANGE
RADIATION BELTS
SATELLITES
TURBULENCE
VARIATIONS