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We present some recent developments on the nuclear many-body problem, such as the treatment of high-order correlations and finite temperature in the description of in-medium two-nucleon propagators. In this work we discuss two-time propagators of the particle-hole type, which describe the response of finite nuclei to external probes without nucleon transfer. The general theory is formulated in terms of the equation of motion method for these propagators with the only input from the bare nucleon-nucleon interaction. The numerical implementation was performed on the basis of the effective mason-nucleon Lagrangian in order to study the energy-dependent kernels of different complexity. The finite-temperature extension of the theory with ph ⊗ phonon configurations is applied to a study of the multipole response of medium-mass nuclei.
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On the dynamical kernels of fermionic equations of motion in strongly-correlated media
Two-point fermionic propagators in strongly-correlated media are considered with an emphasis on the dynamical interaction kernels of their equations of motion (EOM). With the many-body Hamiltonian confined by a two-body interaction, the EOMs for the two-point fermionic propagators acquire the Dyson form and, before taking any approximation, the interaction kernels decompose into the static and dynamical (time-dependent) contributions. The latter translate to the energy-dependent and the former map to the energy-independent terms in the energy domain. We dwell particularly on the energy-dependent terms, which generate long-range correlations while making feedback on their short-range static counterparts. The origin, forms, and various approximations for the dynamical kernels of one-fermion and two-fermion propagators, most relevant in the intermediate-coupling regime, are discussed. Applications to the electromagnetic dipole response of 68,70-Ni and low-energy quadrupole response of 114,116,124-Sn are presented.
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- PAR ID:
- 10512155
- Editor(s):
- Blaschke, David
- Publisher / Repository:
- EDP Sciences, Società Italiana di Fisica and Springer Berlin Heidelberg
- Date Published:
- Journal Name:
- The European Physical Journal A
- Edition / Version:
- 1
- Volume:
- 59
- Issue:
- 12
- ISSN:
- 1434-601X
- Page Range / eLocation ID:
- 1-23
- Subject(s) / Keyword(s):
- Strongly coupled many-body problem, nuclear structure
- Format(s):
- Medium: X Size: 851KB Other: pdf
- Size(s):
- 851KB
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1140/epja/s10050-023-01198-y
