Determination of Q0 and k0 factors for 75Se

Since the initial determination of the Q0 and k0 factors for 75Se systematic errors in Se determination in various matrices have been noticed by several users of the k0 method. A number of publications have been made on this subject, resulting in different k0 and Q0 values for this radio-isotope. This work consists of a re-determination of Q0 and k0 values for 75Se using the bare and Cd-ratio methods making use of three different irradiation channels from the BR1 reactor. For this re-determination three different kinds of standards were used: a pure Se powder standard, an ICP standard solution and pure Se shots. Results were compared with previously published literary data. Differences in k0 with the official published data ranging from 3.5 to 12 % were observed and potential reasons for this discrepancy are discussed. A good consistency with recent work was found. The impact on recent certification and intercomparison exercises demonstrates the effectiveness of the newly proposed values.