Speaker
Description
I will present selected results on nuclear giant and pygmy resonances at zero and finite temperatures based on the recent advancements of the nuclear many-body theory [1-6]. The theory will be compactly introduced in the most general quantum field theory formalism with only the bare fermionic interaction input. A special focus will be placed on the emergent scale of the quasiparticle-vibration coupling (qPVC) with the order parameter associated with the qPVC vertex and an efficient treatment of the nuclear many-body problem organized around the qPVC hierarchy [1-3].
Self-consistent solutions of the relativistic Bethe-Salpeter-Dyson equation for the nuclear response function in medium-heavy nuclei will be presented and discussed. Low-multipole neutral and charge-exchange resonances in calcium, nickel, and tin mass regions will be analyzed in the context of the role of high-complexity configurations in reproducing spectral data [2,3,7]. Finite-temperature theory and implementations for astrophysically relevant low-energy dipole strength, beta decay rates, and electron capture rates will be overviewed in light of the temperature dependence of the nuclear spectral properties [4,5]. Finally, I will outline the prospect of the quantum equation of motion to generate complex configurations for the response of strongly correlated fermionic systems based on an example of the solvable Lipkin Hamiltonian [3].
References
[1] E. Litvinova and Y. Zhang, Microscopic response theory for strongly-coupled superfluid fermionic systems, Phys. Rev. C 106, 064316 (2022).
[2] E. Litvinova, On the dynamical kernels of fermionic equations of motion in strongly-correlated media, Eur. Phys. J. A59, 291 (2023).
[3] J. Novak, M. Q. Hlatshwayo, and E. Litvinova, Response of strongly coupled fermions on classical and quantum computers, arXiv:240502255.
[4] E. Litvinova and H. Wibowo, Finite-temperature relativistic nuclear field theory: an application to the dipole response, Phys. Rev. Lett. 121, 082501 (2018).
[5] E. Litvinova, C. Robin, and H. Wibowo, Temperature dependence of nuclear spin-isospin response and beta decay in hot astrophysical environments, Phys. Lett. B800, 135134 (2020).
[6] S. Bhattacharjee and E. Litvinova, Response of superfluid fermions at finite temperature, arXiv:2412.20751.
[7] M. Markova, P. von Neumann-Cosel, and E. Litvinova, Systematics of the low-energy electric dipole strength in the Sn isotopic chain, Phys. Lett. B860, 139216 (2025).
