OCEAN is BSE code for core spectroscopy.

OCEAN is a code for calculating near-edge x-ray spectra using the Bethe-Salpeter
equation (BSE) is briefly reviewed. The code is capable of calculating UV/Vis,
near-edge x-ray absorption or non-resonant scattering, and resonant inelastic
x-ray scattering, requiring only the structure of the material as input.
Improved default behavior and reduced input requirements are detailed as well as
new capabilities, such as incorporation of final-state-dependent broadening,
finite-temperature dependence, and flexibility in the density-functional theory
exchange-correlation potentials.