Automated calculation of spin, isospin branching rules for su(4) irreps

Abstract

The open-source Python package, su4-branching, is introduced for the derivation of comprehensive spin S and isospin T branching rules for any SU(4) irreducible representation.The Wigner supermultiplet scheme in nuclear and hadronic physics is based on SU(4) symmetry. However, the community does not have easy access to practical calculations of branching rules for any irreps.Our implementation combines group-theoretical methods with a notebook interface that is easy to use. This lets researchers look at large and complicated SU(4) irreps and check their work.The software produces tables, CSV files, and visual summaries, and it has been tested against both classic and modern reference results. This work enables group-structure investigations in nuclear modeling, particle physics, and quantum chemistry.