Study of Gamma Irradiation Induced Conductivity in Dielectric Materials of Coaxial Cables

Organic polymers like Polyethylene and Teflon are used in the most of coaxial cables for insulation purposes. When dielectric insulators are subjected to ionizing radiation, radiation induced conductivity is observed. Thus, ionizing radiation deteriorates the insulating properties of these insulators resulting in a steady state current during the radiation exposure. Solid state band model of polyethylene and Teflon is numerically solved to study the electron density in conduction band in the presence of the radiation and after the exposure of radiation. Polyethylene and Teflon are irradiated by 10ns FWHM triangular and rectangular pulses of 10keV monoenergetic X-rays. Conduction electron densities, calculated from solid state band model, are utilized to determine the time dependent conductivities of these two organic materials for the short time pulses.