Evaluation of the 182Ta radiative strength function via χ^2-weighted model averaging
DOI:
https://doi.org/10.54939/1859-1043.j.mst.111.2026.104-111Keywords:
Radiative strength function; 182Ta; χ^2-weighted model.Abstract
Determining the radiative strength function (RSF) for 182Ta is currently hindered by fragmented experimental coverage, leaving significant discrepancies between theoretical models, especially in the regions where experimental data are unavailable. This work addresses this gap by evaluating an ensemble of 78 E1 and M1 model combinations using a -weighted averaging method constrained by total experimental strength data from the Oslo method. Among the models tested, the Hartree-Fock-Bogoliubov plus quasiparticle random phase approximation with the D1M Gogny force framework exhibits the highest consistency with experimental observations. This is followed by the microscopic exact pairing plus phonon-damping model. In general, our results demonstrate that this data-driven weighting significantly reduces theoretical variance.
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