Effect of toroidicity on the longitudinal permittivity of a magnetized plasma

The paper is devoted to obtaining simpler expressions for longitudinal permittivity ε33 of the magnetized plasma in toroidal tokamak devices and to investigating of ε33 expression found from the point of view of the toroidicity effect on different relations between plasma and field parameters. A model of the collisionless high-temperature plasma, described by the Vlasov equation, is chosen for calculation. The considerable carried out allows to make the following conclusions: the imaginary part of longitudinal dielectric permittivity (Imε33) responsible for the Cherenkov wave attenuation is changed under the influence of toroidal effects; the toroidicity effect on Imε33 increases with frequency reduction; in the frequency range investigated the toroidal effects, if they are substantial, give the contribution into Imε33 of such a sign, which leads to absorption increase in the given harmonics