We present binding energies and properties of wave functions for the light hypernuclei HΛ3, HΛ4, and HeΛ4 based on realistic hyperon–nucleon and nucleon–nucleon interactions including Λ–Σ conversion. ...For the solution, the non-relativistic Schrödinger equation is rewritten into Faddeev or Yakubovsky equations which are solved in momentum space. The accuracy of the numerical calculations is discussed. Based on first leading and next-to-leading order chiral interactions, we discuss the possibility to constrain the hyperon–nucleon interactions by hypernuclear binding energies. Finally, we predict the charge-symmetry breaking of the Λ separation energies of HΛ4/HeΛ4.
The
Λ
N
and
Σ
N
interactions are considered at next-to-leading order in SU(3) chiral effective field theory. Different options for the low-energy constants that determine the strength of the contact ...interactions are explored. Two variants are analysed in detail which yield equivalent results for
Λ
N
and
Σ
N
scattering observables but differ in the strength of the
Λ
N
→
Σ
N
transition potential. The influence of this difference on predictions for light hypernuclei and on the properties of the
Λ
and
Σ
hyperons in nuclear matter is investigated and discussed. The effect of the variation in the potential strength of the
Λ
N
-
Σ
N
coupling (also called
Λ
-
Σ
conversion) is found to be moderate for the considered
Λ
3
H
and
Λ
4
He
hypernuclei but sizable in case of the matter properties. Further, the size of three-body forces and their relation to different approaches to hypernuclear interactions is discussed.
We present the first quantum Monte Carlo (QMC) calculations with chiral effective field theory (EFT) interactions. To achieve this, we remove all sources of nonlocality, which hamper the inclusion in ...QMC calculations, in nuclear forces to next-to-next-to-leading order. We perform auxiliary-field diffusion Monte Carlo (AFDMC) calculations for the neutron matter energy up to saturation density based on local leading-order, next-to-leading order, and next-to-next-to-leading order nucleon-nucleon interactions. Our results exhibit a systematic order-by-order convergence in chiral EFT and provide nonperturbative benchmarks with theoretical uncertainties. For the softer interactions, perturbative calculations are in excellent agreement with the AFDMC results. This work paves the way for QMC calculations with systematic chiral EFT interactions for nuclei and nuclear matter, for testing the perturbativeness of different orders, and allows for matching to lattice QCD results by varying the pion mass.
We discuss the current status of chiral effective field theory in the three-nucleon sector and present selected results for nucleon–deuteron scattering observables based on semilocal ...momentum-space-regularized chiral two-nucleon potentials together with consistently regularized three-nucleon forces up to third chiral order. Using a Bayesian model for estimating truncation errors, the obtained results are found to provide a good description of the experimental data. We confirm our earlier findings that a high-precision description of nucleon–deuteron scattering data below pion production threshold will require the theory to be pushed to fifth chiral order. This conclusion is substantiated by an exploratory study of selected short-range contributions to the three-nucleon force at that order, which, as expected, are found to have significant effects on polarization observables at intermediate and high energies. We also outline the challenges that will need to be addressed in order to push the chiral expansion of three-nucleon scattering observables to higher orders.
Results for the ΛN and ΣN interactions obtained at next-to-leading order in chiral effective field theory are reported. At the order considered there are contributions from one- and ...two-pseudoscalar-meson exchange diagrams and from four-baryon contact terms without and with two derivatives. SU(3) flavor symmetry is imposed for constructing the hyperon–nucleon interaction, however, the explicit SU(3) symmetry breaking by the physical masses of the pseudoscalar mesons (π, K, η) and of the involved baryons is taken into account. An excellent description of the hyperon–nucleon system can be achieved at next-to-leading order. It is on the same level of quality as the one obtained by the most advanced phenomenological hyperon–nucleon interaction models.
We present predictions for the binding energies of the light hypernuclei
Λ
3
H
,
Λ
4
He
and
Λ
4
H
based on Faddeev- and Yakubovsky equations in momentum space. We discuss how such results can help to ...test the existing hyperon–nucleon (
Y N
) potential models and effective field theory based
Y N
interactions. Especially, we show results for the chiral interactions at next-to-leading order.
A
bstract
We show that the proposed measurements of the electric dipole moments of light nuclei in storage rings would put strong constraints on models of flavor-diagonal CP violation. Our analysis ...is exemplified by a comparison of the Standard Model including the QCD theta term, the minimal left-right symmetric model, a specific version of the so called aligned two-Higgs doublet model, and briefly the minimal supersymmetric extension of the Standard Model. By using effective field theory techniques we demonstrate to what extent measurements of the electric dipole moments of the nucleons, the deuteron, and helion could discriminate between these scenarios. We discuss how measurements of electric dipole moments of other systems relate to the light-nuclear measurements.
Properties of finite nuclei are evaluated with two-nucleon (NN) and three-nucleon (NNN) interactions derived within chiral effective field theory. The nuclear Hamiltonian is fixed by properties of ...the A=2 system, except for two low-energy constants (LECs) that parametrize the short range NNN interaction, which we constrain with the A=3 binding energies. We investigate the sensitivity of 4He, 6Li, 10,11B, and 12,13C properties to the variation of the constrained LECs. We identify observables that are sensitive to this variation and find preferred values that give the best overall description. We demonstrate that the NNN interaction terms significantly improve the binding energies and spectra of mid-p-shell nuclei not just with the preferred choice of the LECs but even within a wide range of the constrained LECs. We find that a very high quality description of these nuclei requires further improvements to the chiral Hamiltonian.
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