Electron Removal in Mercury Afterglows

Abstract

greater the value of LP Then the turbulence of greater scale is not much changed by the magnetic field belonging to turbulence of a smaller scale.The motions which bring about the amplification in the largest dimension considered take place mainly in the plane of the galaxy. Hence, it must be concluded that the magnetic lines of force also run more or less parallel to this plane. Furthermore, for the reasons given above, the magnetic field should be rather homogeneous over distances comparable with this same L. Local differences are to be expected, especially in places where the mass density is above average.The magnetic term in the equation of motion, Eq.(2), acts in the direction perpendicular to the plane of the galaxy-on the average as a force directed away from the plane. Also, the pressiire exerted by the cosmicray particles acts in the same direction. Both must be compensated for by the gravitational force. It now seems likely that these are the most essential factors governing the lateral extension of interstellar matter.The interstellar gas clouds commonly observed with high dispersion 16 should be strongly affected by the magnetic field. Components of motion perpendicular to H are not prohibited, but they must be of such character that no permanent lengthening of the lines of force results (e.g., oscillatory). 17 This is equivalent to the statement that the mean square of the (irregular) velocity difference v between two points, whose separation is L, increases with increasing L. The Kolmogoroff-Weizsacker theory of isotropic statistical turbulence predicts v~L* for an incompressible fluid.Observations of the electron density, visible and near ultraviolet light intensity, and spectrum associated with a 2800-Me pulsed electrodeless discharge through mercury vapor have been made. Our results indicate ambipolar diffusion as the principal mechanism of electron removal at low pressure, with attachment becoming increasingly important at higher pressure. The data also yield a considerable amount of information regarding electron temperatures, recombination coefficient, and other parameters necessary to a detailed description of the processes taking place in the discharge.