Numerical Detailing of the Mechanism Responsible for Artificial Heating of the Ionosphere by Powerful High Frequency Radio Waves

High frequency polarization observations reveal the existence of a large-scale ordered magnetic field in the disk of the spiral galaxy NGC 6946. At lower frequencies the disk is no longer transparent to polarized radio waves due to Faraday depolarization. The spiral pattern of the uniform magnetic field and the distribution of polarized intensities are fairly well simulated by a dynamo model. The model parameters indicate that the dynamo does not only operate in the disk, but also in the halo.

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An Airplane Psychrograph*

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-28.8.363 ◽

1947 ◽

Vol 28 (8) ◽

pp. 363-370 ◽

Cited By ~ 1

Author(s):

Isadore Katz

Keyword(s):

Water Vapor ◽

High Frequency ◽

Radio Waves ◽

Ultra High Frequency ◽

Anomalous Propagation

An airplane psychrograph has been designed to make measurements in the lowest several thousand feet of the atmosphere. These measurements are necessary in order to understand the phenomena causing anomalous propagation associated with the ultra-high frequency radio waves used for radar. The instrument employs ceramic resistors as wet and dry elements; they are rapid in response and sensitive enough for measuring sharp gradients of temperature and water vapor usually present close to the boundary between the air and the water or land. Detail of the construction and use of the airplane psychrograph are described.

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Variations in the direction of arrival of high-frequency radio waves

Journal of Atmospheric and Terrestrial Physics ◽

10.1016/0021-9169(58)90019-9 ◽

1958 ◽

Vol 13 (1-2) ◽

pp. 17-25 ◽

Cited By ~ 9

Author(s):

J.E. Titheridge

Keyword(s):

High Frequency ◽

Direction Of Arrival ◽

Radio Waves

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Diffusion spreading of middle-latitude ionospheric plasma irregularities

Annales Geophysicae ◽

10.1007/s00585-995-0617-7 ◽

1995 ◽

Vol 13 (6) ◽

pp. 617-626 ◽

Cited By ~ 7

Author(s):

N. Blaunstein

Keyword(s):

Ionospheric Plasma ◽

Three Dimensional ◽

Middle Latitude ◽

Approximate Model ◽

Ionospheric Irregularities ◽

Radio Waves ◽

Plasma Irregularities ◽

Relaxation Effects ◽

Artificial Heating ◽

Actual Height

Abstract. In contrast to the way that the spreading of irregularities in a plasma is usually considered, the diffusion spreading of irregularities stretched along the geomagnetic field B is examined using a three-dimensional rigorous numerical model of quasi-neutral diffusion in the presence of a magnetic field, in conjunction with the actual height variations of the diffusion and conductivity tensors in the ionosphere. A comparison with the earlier constructed approximate model of unipolar diffusion was made. As in the previous case, the same peculiarities of irregularity spreading in the inhomogeneous background ionospheric plasma were observed. The accuracy of the approximate model for describing the process of spreading of anisotropic ionospheric irregularities is established. Time relaxation effects of real heating-induced ionospheric irregularities on their scale transverse to B are presented using the approximate analytical model for the case of a quasi-homogeneous ionospheric plasma. The calculated results have a vivid physical meaning and can be directly compared with experimental data on the radiophysical observations of artificial heating-induced irregularities created by powerful radio waves in the ionosphere.

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