Determination of k0-values for the reactions 94Zr (n, gamma) 95Zr and 96Zr (n, gamma) 97Zr-97mNb by irradiation in highly thermalized neutron flux.

Determination of k(0)-factors for zirconium isotopes was performed by co-irradiation of Zr and Au-Al. Due to the highly thermalized irradiation position at FRM-II, interferences from epithermal neutrons were found largely decreased for (96)Zr (n, gamma) (97)Zr-(97m)Nb, the reaction with the highest Q(0)-value in all (n, gamma) reactions. Results showed that, the (95)Zr k(0)-values from this work were the same as the recommended ones. For (97)Zr-(97m)Nb 743.4 keV gamma-line, the new k(0)-value was 2.8% higher compared to the recommended value, which is not a significant difference. These results are helpful in clarifying the suspicion about the Zr k(0)-factors.