Inactivation and mutation of cultured mammalian cells by aluminium characteristic ultrasoft X-rays. I. Properties of aluminium X-rays and preliminary experiments with Chinese hamster cells.

Irradiation with ultrasoft X-rays produces electron tracks of short defined lengths in the irradiated material. This property is of particular interest in distinguishing between different models of radiation action on living organisms. The production, absorption and dosimetry of aluminium K characteristic X-rays of energy 1.5 keV are described. Quantitative experiments on mammalian cells with these X-rays are possible, and they were found to be considerably more effective than gamma-rays in inactivating Chinese hamster V79 cells in vitro.