Guiding of electromagnetic waves along a magnetic field in a plasma

Journal Article · Tue Jan 15 04:00:00 EST 1963 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/JZ068i002p00387· OSTI ID:4718358

Rao, M. S. V. Gopal; Booker, H. G.

Using ray theory and assuming iongitudinal propagation conditions, the circumstances in which curvature of the ray is identicai with curvature of the magnetic field are investigated. ln general the two curvatures are only identical if there exists an appropriate transverse gradient of the plasma density. For a given ratio of the wave frequency to the gyrofrequency, and of the plasma frequency to the gyrofrequency, the necessary transverse gradient of plasma density may be calculated as a ratio to the curvature of the magnetic fieid, Curves have been prepared showing, for a wide range of values of the parameters, the transverse gradient of plasma density required to make the ray curvature identical with the field curvature. Of particular interest are the conditions in which no transverse gradient of plasma density is required to make the ray curvature identical with the field curvature. In these circumstances waves are guided by the magnetic field even in a homogeneous piasma. It is found that at hydromagnetic frequencies (wave frequency less than the ionic gyrofrequency) such guiding never occurs. Indeed, at frequencies small compared with the ionic gyrofrequency the ray curvature is equai to the field curvature in magnitude but opposite in sign. Above about twice the ionic gyrofrequency, field guiding is possible in a homogeneous piasma for the left-hand wave (O wave) but not for the right-hand wave (X wave), provided that the homogeneous plasma density is adjusted to an appropriate value. (auth)

• Research Organization: Cornell Univ., Ithaca, N.Y.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-009709
• OSTI ID: 4718358
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: 2 Vol. 68; ISSN 0148-0227
• Publisher: American Geophysical Union
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

CONFIGURATION
CYCLOTRON FREQUENCY
DENSITY
DIAGRAMS
ELECTROMAGNETIC WAVES
FREQUENCY
GYROFREQUENCY
HOMOGENEOUS REACTORS
IONS
LIGHT
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MOTION
NUMERICALS
PHYSICS
PLASMA
ROTATION
SPIN