dielectric dispersion
1.Here, the effect of the longitudinal uniform magnetic field on the wave-beam interaction of the plasma dielectric Cherenkov maser is examined by solving the beam-plasma, dielectric lined waveguide dispersion equation. And the effects of the longitudinal magnetic field, plasma density and dielectric parameters on the linear spatial growth rate and the energy ratio are presented.
2.Using the self-consistent linear field theory, Cherenkov radiation excitated by the beam-wave interaction of a thin annular relativistic electron beam in a plasma-filled, dielectric coaxial cylindrical waveguide was analyzed. The dispersion equation of the interaction, the synchronized condition and the wave growth rate were derived.
3.Pb[(Zn1/3Nb2/3)0.91Ti0.09]O3(PZNT91/9) single crystals were grown by a modified Bridgman technique with an allomeric seed and PbO flux. Temperature dependence of dielectric constant for PZNT91/9 single crystal displays apparent frequency dispersion.
4.When doped with Li2O, the maximum dielectric constant of this material is 28640, which is higher than that of pure PMN-10PT, while the degree of frequency dispersion and DPT are decreased.
5.It is found that the PA-6 particle size, dispersion and the interface adhesion between PA-6 and PP matri x influence the dielectric properties of the blends.
6.In this paper a newly develoed helical coordinates is used to make out the solution of electromagnetic fields in the helix gap and calculate dispersion characteristics of tape helix slow wave structure for the first time.Strict boundary conditions for magnetic fields are adopted and are treated rigorously by Fourier expansion.Besides,the radial propagation constant of every layer in the dielectric-loaded region is differentiated.Some of practical tape helix slow wave structures have been calculated for dispersion characteristics and the calculated values accord with measured values very well.The authors also compare the calculated results with experiments for different structures by changing tape thickness or other structure parameters and find that the theory in the paper is universal.
7.Cherenkov radiation produced by an axial solid relativistic electron beam in a plasma filled dielectric lined slow wave waveguide was analyzed by the use of the self consistent linear field theory considering the three dimensional perturbation of electrons. The dispersion equation,which describes the instability,and the simultaneous condition of the beam wave interaction were derived. Finally,the growth rate of the wave was obtained,and the effects of the background plasma density and the electron beam radius on the growth rate of the wave were presented.
