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arXiv · 2310.16133

The renormalization of the shell-model GT operator starting from effective field theory for nuclear systems

L. Coraggio·N. Itaco·G. De Gregorio·A. Gargano·Z. H. Cheng·Y. Z. Ma·F. R. Xu·M. Viviani
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Abstract

For the first time, we approach in this work the problem of the renormalization of the Gamow-Teller decay operator for nuclear shell-model calculations by way of many-body perturbation theory, starting from a nuclear Hamiltonian and electroweak currents derived consistently by way of the chiral perturbation theory. These are the inputs we need to construct microscopically the effective shell-model Hamiltonians and decay operators. The goal is to assess the role of both electroweak currents and many-body correlations as the origins of the well-known problem of the quenching of the axial coupling constant gA. To this end, the calculation of observables related to the Gamow-Teller transitions has been performed for several nuclear systems outside the 40Ca and 56Ni closed cores and compared with the available data.

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L. Coraggio, N. Itaco, G. De Gregorio, A. Gargano, Z. H. Cheng, Y. Z. Ma, F. R. Xu, M. Viviani. 2023-10-24. The renormalization of the shell-model GT operator starting from effective field theory for nuclear systems. https://arxiv.org/abs/2310.16133

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