RAYONNEMENT FORTEMENT ACCRU PRÉSENTÉ PAR UNE ANTENNE ENROBÉE D'UNE GAINE DIÉLECTRIQUE ET D'UNE COUCHE DE PLASMA

1967 ◽  
Vol 45 (10) ◽  
pp. 3367-3380
Author(s):  
A. M. Messiaen ◽  
P. E. Vandenplas
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Dielectric Layer ◽  
Essential Role ◽  
Plasma Layer ◽  
Plasma Sheath ◽  
Operating Frequency

The plasma sheath existing between an antenna and a surrounding plasma layer plays an essential role. It is predicted that, for a given operating frequency, there exist certain plasma densities for which the system is resonant, and this very strongly enhanced radiation is fully confirmed by experiments. This combination of dielectric layer and plasma enables to tune an antenna even when its dimensions are much smaller than the vacuum wavelength. The influence of a static magnetic field is discussed.The same system can also be used as a frequency-sensitive receiving aerial.

EFFECT OF STATIC MAGNETIC FIELD ON RADIATION THROUGH A PLASMA SHEATH

1966 ◽  
Vol 44 (9) ◽  
pp. 1941-1964 ◽  
Author(s):  
S. R. Seshadri ◽  
G. L. Yip
Keyword(s):  
Magnetic Field ◽  
Radiation Pattern ◽  
Static Magnetic Field ◽  
Radiation Resistance ◽  
Plasma Column ◽  
Guided Waves ◽  
Plasma Sheath ◽  
Radiation Characteristics ◽  
Current Filament ◽  
Uniform Plasma

The radiation characteristics of a filament of finite length with a triangular current distribution are investigated for the case in which it is situated along the axis of an infinitely long, axially magnetized column of uniform plasma. In general, the current filament will excite guided waves along the plasma column as well as space waves. The radiation pattern in the far zone and the radiation resistance of the current filament contributed by the space waves are studied as a function of the radius of the plasma column, the operating frequency of the source, the strength of the applied static magnetic field, and the length of the current filament with the current at its center kept constant. In particular, for various frequencies below the plasma frequency and for a particular radius of the plasma column, the radiation pattern and the radiation resistance are presented as a function of the strength of the applied static magnetic field. These results indicate that a significant improvement in the transmission through a plasma sheath can be obtained by a suitable application of a static magnetic field. A brief discussion of the characteristics of the possible guided waves along the plasma column is also included.

ELECTROMAGNETIC RADIATION FROM AN ARBITRARY SLOT ON A CONDUCTING CYLINDER COATED WITH A UNIFORM COLD PLASMA SHEATH WITH AN AXIAL STATIC MAGNETIC FIELD

1964 ◽  
Vol 42 (7) ◽  
pp. 1369-1381 ◽  
Author(s):  
C. Yeh
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Cold Plasma ◽  
Considerable Effect ◽  
Plasma Sheath ◽  
Slot Antenna ◽  
Radiation Patterns ◽  
Conducting Cylinder ◽  
Slotted Antenna ◽  
Axial Static Magnetic Field

The expressions for the radiated fields of an arbitrary slot on a conducting cylinder coated with a cold plasma sheath with an axial static magnetic field are obtained. It is well known from the plane-wave analysis that the presence of a static magnetic field has a considerable effect on the transmission characteristics of the signal through the plasma sheath. The principal concern of this paper is to consider the effects of a static magnetic field on the radiation pattern of a plasma-coated slot antenna. Extensive numerical computations are carried out for the special case of an infinite axial slot. It is found that, if the plasma frequency is moderate, a small axial static magnetic field could change significantly the radiation patterns of the slotted antenna. Furthermore, owing to the anisotropy of the plasma medium, the radiation patterns are asymmetric.

Faint Hα Emission in the Corona and Its Relation to the Prominences

1994 ◽  
Vol 144 ◽  
pp. 339-342
Author(s):  
V. N. Dermendjiev ◽  
Z. Mouradian ◽  
J.- L. Leroy ◽  
P. Duchlev
Keyword(s):  
Magnetic Field ◽  
Solar Corona ◽  
Essential Role ◽  
Hα Emission

AbstractThe relation between episodically observed in the solar corona faint Hαemission structures and the long lived prominences was studied. Particular consideration was given for cases in which the corresponding prominences had undergone DB process. An MHD interpretation of the phenomenon “emissions froides” (cool emission) is proposed in which an essential role plays the prominence supporting magnetic field.

Decreased chemotaxis of human peripheral phagocytes exposed to a strong static magnetic field

2004 ◽  
Vol 91 (1) ◽  
pp. 59-65 ◽  
Author(s):  
S Sipka ◽  
I Szöllősi ◽  
Gy Batta ◽  
Gy Szegedi ◽  
Á Illés ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field

Intense Static Magnetic Field Induced Bone Growth in Vivo

1984 ◽  
Vol 3 (1) ◽  
pp. 223-234
Author(s):  
Frank Papatheofanis ◽  
Bill Fapatheofanls ◽  
Robert Ray
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Bone Growth
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