Hydromagnetic emissions, X-ray bursts, and electron bunches: 2. Theoretical interpretation

Journal Article · Wed Aug 01 04:00:00 EDT 1962 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/JZ067i009p03335· OSTI ID:4761500

Wentworth, R. C.; Tepley, L. R.

The existence of bunches of monoenergetic electrons oscillating back and forth along field lines in the magnetosphere has been suggested by a number of workers to explain various geophysical phenomena. The simultaneous occurrence of x-ray and hydromagnetic emission bursts (regular oscillatory micropulsations at frequencies in the range 1-2 cps) immediately after sudden commencements and during magnetically disturbed periods, as discussed in part 1, raises the possibility that hm emissions could be generated by such electron bunches. A model is presented that considers certain aspects of the motion of geomagnetically trapped electrons relevant to the production of hm emissions by electron bunches. A new result is the calculation of electron motion in a dipole field confined to the interior of a sphere (as a first approximation to the solar wind cavity). The model calculations are applied to experimental results discussed in part 1, and it is shown that the electrons responsible for the x-ray burst after the sudden commencement of June 27, 1960, could have produced the hm emission burst at that time, and that the maximum observed hm emission frequency as a function of geomagnetic latitude is consistent with the calculated value. Hydromagnetic emissions during magnetically quiet times are characterized by a fine structure containing overlapping bands of rapidly increasing frequency. This is tentatively interpreted as indicating rapid acceleration of electron bunches; hence, if the model is correct, hm emissions will provide a powerful tool for studying the acceleration mechanism for electrons in the magnetosphere.

• Research Organization: Lockheed Aircraft Corp., Palo Alto, Calif.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-003924
• OSTI ID: 4761500
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: 9 Vol. 67; ISSN 0148-0227
• Publisher: American Geophysical Union
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ACCELERATION
ACCELERATORS
DIPOLES
DISTRIBUTION
EARTH
ELECTRONS
EMISSION
ENERGY
FREQUENCY
GEOPHYSICS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MOTION
NUMERICALS
OSCILLATIONS
PHYSICS
PULSES
RADIATION BELTS
TURBULENCE
VELOCITY
X RADIATION