Seminar Details

"The Gamow Shell Model as a tool for ab-initio nuclear structure calculations"

Georgios Papadimitriou, University of Arizona
Tuesday, October 2, 11:00 AM - Theory Seminar
NSCL Seminar Room

No-core Gamow shell model (NCGSM) is applied for the first time to study selected well-bound and unbound states of helium isotopes. This model, formulated in the rigged Hilbert space and using a complete Berggren ensemble, is the generalization of the no-core shell model (NCSM) for a description of bound states, resonances, and the many-body scattering states. The ‘dimensional catastrophe’ in NCGSM when increasing the number of active particles is much more serious than in the NCSM because each single-particle continuum state in the Berggren ensemble becomes a new shell in the many-body GSM formulation. This problem has been alleviated by the application of the Density Matrix Renormalization Group (DMRG) method, opening a possibility for the ab initio calculation of exotic states in hydrogen, helium and lithium chains of isotopes. The ab initio NCGSM calculations start from either bare interaction or various renormalized two-body interactions such as Vlow-k. The single-particle Berggren ensemble consisting of bound, resonance and non-resonant continuum states is generated by the corresponding Gamow-Hartree-Fock potential. To test the validity of our approach, we benchmarked the NCGSM results against Fadeev and Fadeev‐Yakubovsky exact calculations for 3H and 4He nuclei. We also performed ab-initio NCGSM calculations for the unstable nucleus 5He and determined the ground state energy and decay width, starting from a realistic N3LO interaction.