[en] In an ongoing experiment, mammalian cells are exposed to pairs of correlated deuterons resulting from the break-up of accelerated deuteron molecules. The purpose is to obtain further information on the question how the microscopic distribution of energy affects the irradiated cell. By varying the average spacing of the correlated deuterons, patterns of microscopic energy distribution are obtained which are characteristically different from those in conventional experiments, where the LET of the radiation is varied. The study deals with the microdosimetry of the molecular beam experment and with the possible inferences that can be drawn if the dependence of the cellular effect on the mean spacing of the deuterons is obtained