Determination of effective resonance energy for the 193Ir(n,γ)194Ir reaction by the cadmium ratio method

In this work, the effective resonance energy, E¯r-value for the 193Ir(n,γ)194Ir reaction was measured using cadmium ratio method. A dual monitor (197Au-98Mo), which has convenient resonance properties, was employed for characterization of the irradiation sites. Then analytical grade iridium oxide samples diluted with CaCO3 to lower neutron self-shielding effect stacked in small cylindrical Teflon boxes were irradiated once with a 1 mm thick Cd cylindrical box placed in a thermalized neutron field of an 241Am-Be neutron source then without it. The activities produced in samples during 193Ir(n,γ)194Ir reaction were measured using a p-type HPGe detector γ-ray spectrometer with a 44.8% relative efficiency. The correction factors for thermal, epithermal neutron self-shielding (Gth, Gepi), true coincidence summing (Fcoi) and gamma-ray self-absorption (Fs) effects were determined with appropriate approaches and programs. Thus, the experimental E¯r-value was determined to be 2.65 ± 0.61 eV for 193Ir target nuclide. The recent data for Q0 and FCd values for E¯r determination were based on k0-NAA online database. The present experimental E¯r value was calculated and compared with more recent values for Q0 and FCd for 193Ir. Additionally, the E¯r-values was theoretically calculated from the up-to-date resonance data obtained from ENDF/B VII library using two different approaches. Since there is no experimentally determined E¯r-value for the 193Ir isotope, the results are compared with the calculated ones given in the literature.