Speaker
Description
The ab initio description of nuclear systems has undergone a major renewal due to the use of low-resolution interactions derived from chiral effective field theory in conjunction with many-body techniques admitting for mild computational scaling [1].
Nowadays many-body practitioners are able to target systems with up to one hundred interacting particles from first principles in a systematically controllable way [2].
In this talk I present recent advances in the field of ab initio nuclear theory in the context of the non-perturbative in-medium similarity renormalization group (IMSRG) approach.
While the many-body expansion is commonly built upon a simple Hartree-Fock state, basis optimisation tools have shown to significantly improve the modelsapce convergence of the calculation [3,4]. In addition, by including three-body contributions induced by the RG flow enables for an improved many-body solution using ab initio technology [5].
Optimising the underlying reference state as well as relaxing the many-body truncation will eventually pave the way for high-precision studies in medium-mass systems.
[1] H. Hergert, Front. Phys. 8, 379 (2020).
[2] T. Morris et al., Phys. Rev. Lett. 120, 152503 (2018)
[3] A. Tichai, J. Müller, K. Vobig and R. Roth, Phys. Rev. C 99, 034321 (2019)
[4] J. Hoppe, A. Tichai, M. Heinz, K. Hebeler and A. Schwenk, Phys. Rev. C 103, 014321 (2021)
[5] M. Heinz, A. Tichai, J. Hoppe, K. Hebeler and A. Schwenk, Phys. Rev. C 103, 044318 (2021)
