Statistical (n, ) cross section model comparison for short-lived nuclei

Area of Science:

• Nuclear physics
• Computational nuclear science
• Astrophysical nucleosynthesis

Background:

• Neutron-capture cross sections are crucial for understanding nucleosynthesis in stars.
• Experimental measurements are often impossible for short-lived, neutron-rich nuclei.
• Hauser-Feshbach statistical models are widely used for these calculations, but different codes exist.

Purpose of the Study:

• To investigate the systematic uncertainty in calculated neutron-capture cross sections arising from the choice of Hauser-Feshbach code.
• To assess the impact of experimental nuclear data and consistent physics inputs on code agreement.

Main Methods:

• Calculated neutron-capture cross sections for a specific nucleus using three Hauser-Feshbach codes (TALYS, CoH, EMPIRE).
• Performed calculations with default settings, then with experimental nuclear level density (NLD) and gamma-ray strength function (GSF).
• Ensured consistent nuclear structure information and approximations across codes.

Main Results:

• Initial calculations with default settings showed variations between codes.
• Including experimentally obtained NLD and GSF significantly improved agreement between the three codes.
• Consistent treatment of nuclear physics inputs and experimental data across codes is essential for reliable results.

Conclusions:

• Systematic uncertainties in Hauser-Feshbach calculations can be reduced by using consistent nuclear physics inputs and experimental data.
• Careful investigation and documentation of input parameters and physics choices are vital when comparing results from different codes.
• Standardizing data treatment across codes is necessary for accurate neutron-capture cross-section predictions.