[Neutron therapy in the GDR. IX. About the accuracy of neutron dosimeter systems (author's transl)].

In this report is specified which accuracies must now be achieved in the determination of dose components for neutron therapy of tumors and for evaluation of RBE's after neutron irradiations of various organs from mammals or men. After these introductory remarks the reasons are summarized why the errors in ionimetric measurements of neutron doses are considerably higher than those of gamma-doses. In detail the concept and the errors of the Rossendorf neutron dosimeter system are represented. The latter consists of two spherical homogeneous ionization chambers, each of which is connected to a commercial dosimeter. The results of an intercomparison between our neutron dosimeter and that of DR. Bewley (MRC Cyclotron Unit, Hammersmith Hospital London) carried out at the Rossendorf neutron therapy facility are reported.