Abstrakt
Thermal neutron-capture measurements of the stable tungsten isotopes have been carried out using the guided thermal-neutron beam at the Budapest Reactor. Prompt singles spectra were collected and analyzed using the HYPERMET gamma-ray analysis software package for the compound tungsten systems W-183, W-184, and W-187, prepared from isotopically-enriched samples of W-182, W-183, and W-186, respectively.
These new data provide both confirmation and new insights into the decay schemes and structure of the tungsten isotopes reported in the Evaluated Gamma-ray Activation File based upon previous elemental analysis. The experimental data have also been compared to Monte Carlo simulations of gamma-ray emission following the thermal neutron-capture process using the statistical-decay code DICEBOX.
Together, the experimental cross sections and modeled-feeding contribution from the quasi continuum, have been used to determine the total radiative thermal neutron-capture cross sections for the tungsten isotopes and provide improved decay-scheme information for the structural-and neutron-data libraries.