Inhomogeneous Electrostatic Field Research Articles

18 P 10 Particle transport in an inhomogeneous electrostatic field under laminar flow conditions

18 P 10 Particle transport in an inhomogeneous electrostatic field under laminar flow conditions

Doppler-shifted cyclotron resonance maser driven by an electrostatic pumped beam

A Doppler-shifted cyclotron resonance maser experiment using a 500 keV, 30 nsec high-current electron beam emitted by a Blumlein pulse accelerator has produced approximately 20 and 8 MW at frequencies of 13 and 37 GHz in TE01 and TE03 waveguide modes, respectively. The beam has been electrostatically pumped by means of a strongly inhomogeneous electrostatic field created in the diode region. The experimental results are in a good agreement with the numerical calculations of a cold system electrostatic field and with simulation studies of beam propagation. The transverse electron velocity has been estimated on the basis of the performed computations and experimental measurements.

A transversally and longitudinally focusing time-of-flight mass spectrometer

The time-of-flight mass spectrometer described here has been designed for ions with angle and energy spreads as produced in a real ion source. It performs both transverse and longitudinal focusing. These focusing properties are achieved simultaneously by the inhomogeneous electrostatic field of a rotationally symmetric grid-free ion reflector with conically shaped entrance electrodes. When used in combination with a newly developed longitudinally focusing electron impact ion source, high sensitivity and high mass resolving power are obtained.

“Proper Time” Method Calculation of the “One Loop” Thermodynamical Potential for QED in External Electromagnetic Field

AbstractThe extension of the “proper time” method to the statistical field theory is obtained. The procedure is used to calculate the “one loop” contribution to the thermodynamical potential in electrodynamics, when the electron positron gas is located in a combination of an inhomogeneous electrostatic field and an uniform magnetic one. Also, a “proper time” representation of the temperature Green function for this problem is given.

Investigation of a method of enhancing the efficiency of difference frequency generation by stimulated Raman scattering utilizing an inhomogeneous electrostatic field

An investigation is made of resonance parametric difference-frequency generation by stimulated Raman scattering (STRS) in the presence of a periodically inhomogeneous electrostatic field (externally applied or internal field). The initial and maximum difference-frequency generation intensities are determined for arbitrary relationships between the parameters of the system (difference-frequency absorption coefficient and gain of the STRS Stokes component, wave mismatch, and period of the periodically inhomogeneous electrostatic field). It is found that by generating a periodically inhomogeneous electrostatic field, it is possible to compensate for the decrease in the difference-frequency generation efficiency not only due to the wave mismatch but also due to parametric bleaching. Conditions under which the improvement in the intensity of the difference frequency generation is several orders of magnitude are discussed. By using a periodically inhomogeneous electrostatic field applied to compressed H2, an improvement by a factor of 20–80 was obtained for pumping at λρ = 1.06μ and by a factor of 100 for pumping at λρ = 0.694 μ, in agreement with the estimates obtained using the equations derived in the present paper.

Measurement of the polarizability of calcium

The static electric dipole polarizability of the $4{s}^{2}(^{1}S_{0})$ ground state of the calcium atom has been measured using an electric deflection technique. The result is normalized to the polarizability of lithium by comparing deflections of calcium and lithium beams passing through an inhomogeneous electrostatic field. We find (25 \ifmmode\pm\else\textpm\fi{} 2.5) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}24}$ ${\mathrm{cm}}^{3}$ for the polarizability of calcium.

Measurement of the static electric dipole polarizabilities of barium and strontium

The static electric dipole polarizabilities of barium and strontium atoms have been measured using an electric deflection technique. The results are normalized to the polarizability of lithium by comparing deflections of the alkaline-earth beams to deflections of a lithium beam passing through an inhomogeneous electrostatic field. The measured polarizabilities are (39.7 \ifmmode\pm\else\textpm\fi{} 3.2) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}24}$ ${\mathrm{cm}}^{3}$ for barium and (27.6 \ifmmode\pm\else\textpm\fi{} 2.2) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}24}$ ${\mathrm{cm}}^{3}$ for strontium.