Development of a new website for Nuclear Level Densities

Nuclear level density (NLD) refers to the number of energy levels available to a nucleus at a given excitation energy. NLDs are crucial for determining reaction rates in astrophysical scenarios, but they carry significant uncertainties. Existing databases, like RIPL, primarily rely on level densities estimated from the neutron resonance spacing data which are limited in terms of spin and excitation energy ranges, contributing to the uncertainty of models used in calculations. To further constrain level density models, we have developed a new nuclear level density database that hosts data from a range of experimental techniques across various excitation energies. Users can search by proton and mass number, extraction method, reaction type, or evaluation status. Datasets generate level density plots vs. excitation energy, with options for linear or semi-logarithmic scales. Users can compare datasets in split-mode and fit them to models like the constant temperature and back-shifted Fermi gas, with best-fit parameters and uncertainties provided. Data files are also available for download.

This presentation will showcase the database and early analyses performed on the data sets. Results of the analyses will be applied to extract a new analytic formula for NLD and this new formula will be employed in the calculation of astrophysical reaction rates.