THE EFFECT OF ELECTRIC FIELDS, AND A RELATED DEPENDENCE ON DOSE RATE, IN THE γ-RADIOLYSIS OF HYDROCARBON GASES

Abstract

The effect of electric fields on the γ-radiolysis of ethane, propane, and the butanes has been investigated briefly at 800 mm pressure, with dose rates between 2 × 10¹⁰ and 400 × 10¹⁰ ev/cc sec. Yields of hydrogen were reduced when a saturation field was applied, except with ethane at low dose rate, where a slight increase in hydrogen yield was observed. With propane and n-butane, the yield of hydrogen in the presence of a saturation field was independent of dose rate, while with ethane, it decreased with decreasing dose rate. At the same time, a dose rate dependence was discovered in the simple radiolysis, in the absence of any field, of ethane, propane, and n-butane, a decrease in the yield of hydrogen at low dose rates being observed. An explanation of these observations is suggested in terms of a competition between neutralization of ions in the gas phase and diffusion of ions to the wall. High dose rates should favor the former process, and low dose rates the latter. At sufficiently high dose rates, all ions should be neutralized in the gas phase. At sufficiently low dose rates, all ions should diffuse to the wall before neutralization, and it is suggested that the radiolysis under these conditions should closely resemble that in the presence of a saturation field at higher dose rates.