Davesne, D., Holt, J. W., Pastore, A., & Navarro, J. (2015). Effect of three-body forces on response functions in infinite neutron matter. Phys. Rev. C, 91(1), 014323–7pp.
Abstract: We study the impact of three-body forces on the response functions of cold neutron matter. These response functions are determined in the random phase approximation from a residual interaction expressed in terms of Landau parameters. Special attention is paid to the noncentral part, including all terms allowed by the relevant symmetries. Using Landau parameters derived from realistic nuclear two-and three-body forces grounded in chiral effective field theory, we find that the three-body term has a strong impact on the excited states of the system and in the static and long-wavelength limit of the response functions for which a new exact formula is established.
|
Davesne, D., Pastore, A., & Navarro, J. (2021). Linear response theory with finite-range interactions. Prog. Part. Nucl. Phys., 120, 103870–55pp.
Abstract: This review focuses on the calculation of infinite nuclear matter response functions using phenomenological finite-range interactions, equipped or not with tensor terms. These include Gogny and Nakada families, which are commonly used in the literature. Because of the finite-range, the main technical difficulty stems from the exchange terms of the particle-hole interaction. We first present results based on the so-called Landau and Landau-like approximations of the particle-hole interaction. Then, we review two methods which in principle provide numerically exact response functions. The first one is based on a multipolar expansion of both the particle-hole interaction and the particle-hole propagator and the second one consists in a continued fraction expansion of the response function. The numerical precision can be pushed to any degree of accuracy, but it is actually shown that two or three terms suffice to get converged results. Finally, we apply the formalism to the determination of possible finite-size instabilities induced by a finite-range interaction.
|
Davesne, D., Pastore, A., & Navarro, J. (2016). Extended Skyrme equation of state in asymmetric nuclear matter. Astron. Astrophys., 585, A83–11pp.
Abstract: We present a new equation of state for infinite systems (symmetric, asymmetric, and neutron matter) based on an extended Skyrme functional that has been constrained by microscopic Brueckner-Bethe-Goldstone results. The resulting equation of state reproduces the main features of microscopic calculations very accurately and is compatible with recent measurements of two times Solar-mass neutron stars. We provide all necessary analytical expressions to facilitate a quick numerical implementation of quantities of astrophysical interest.
|
Davesne, D., Meyer, J., Pastore, A., & Navarro, J. (2015). Partial wave decomposition of the N3LO equation of state. Phys. Scr., 90(11), 114002–6pp.
Abstract: By means of a partial wave decomposition, we separate their contributions to the equation of state (EoS) of symmetric nuclear matter for the N3LO pseudo-potential. In particular, we show that although both the tensor and the spin-orbit terms do not contribute to the EoS, they give a non-vanishing contribution to the separate (JLS) channels.
|
Davesne, D., Navarro, J., Meyer, J., Bennaceur, K., & Pastore, A. (2018). Two-body contributions to the effective mass in nuclear effective interactions. Phys. Rev. C, 97(4), 044304–7pp.
Abstract: Starting from general expressions of well-chosen symmetric nuclear matter quantities derived for both zero-and finite-range effective theories, we derive some universal relations between them. We first showthat, independently of the range, the two-body contribution is enough to describe correctly the saturation mechanism but gives an effective mass value around m(*)/m similar or equal to 0.4 when the other properties of the saturation point are set near their generally accepted values. Then, we show that a more elaborated interaction (for instance, an effective two-body density-dependent term on top of the pure two-body term) is needed to reach the accepted value m(*)/m similar or equal to 0.7-0.8.
|
Davesne, D., Becker, P., Pastore, A., & Navarro, J. (2016). Infinite matter properties and zero-range limit of non-relativistic finite-range interactions. Ann. Phys., 375, 288–312.
Abstract: We discuss some infinite matter properties of two finite-range interactions widely used for nuclear structure calculations, namely Gogny and M3Y interactions. We show that some useful informations can be deduced for the central, tensor and spin orbit terms from the spin-isospin channels and the partial wave decomposition of the symmetric nuclear matter equation of state. We show in particular that the central part of the Gogny interaction should benefit from the introduction of a third Gaussian and the tensor parameters of both interactions can be deduced from special combinations of partial waves. We also discuss the fact that the spin orbit of the M3Y interaction is not compatible with local gauge invariance. Finally, we show that the zero-range limit of both families of interactions coincides with the specific form of the zero-range Skyrme interaction extended to higher momentum orders and we emphasize from this analogy its benefits.
|
Davesne, D., Becker, P., Pastore, A., & Navarro, J. (2016). Partial-wave decomposition of the finite-range effective tensor interaction. Phys. Rev. C, 93(6), 064001–6pp.
Abstract: We perform a detailed analysis of the properties of the finite-range tensor term associated with the Gogny and M3Y effective interactions. In particular, by using a partial-wave decomposition of the equation of state of symmetric nuclear matter, we show how we can extract their tensor parameters directly from microscopic results based on bare nucleon-nucleon interactions. Furthermore, we show that the zero-range limit of both finite-range interactions has the form of the next-to-next-to-next-leading-order (N3LO) Skyrme pseudopotential, which thus constitutes a reliable approximation in the density range relevant for finite nuclei. Finally, we use Brueckner-Hartree-Fock results to fix the tensor parameters for the three effective interactions.
|
Davesne, D., Navarro, J., Becker, P., Jodon, R., Meyer, J., & Pastore, A. (2015). Extended Skyrme pseudopotential deduced from infinite nuclear matter properties. Phys. Rev. C, 91(6), 064303–6pp.
Abstract: We discuss the contributions to the equation of state for the NlLO Skyrme pseudopotential (l = 2,3). We show that by adding fourth- and sixth-order gradient terms, it is possible to fairly reproduce the spin/isospin decomposition of an equation of state obtained from ab initio methods. Moreover, by inspecting the partial-wave decomposition of the equation of state, we show for the first time a possible way to add explicit constraints on the sign of the tensor terms of the Skyrme interaction.
|
Becker, P., Davesne, D., Meyer, J., Pastore, A., & Navarro, J. (2015). Tools for incorporating a D-wave contribution in Skyrme energy density functionals. J. Phys. G, 42(3), 034001–19pp.
Abstract: The possibility of adding a D-wave term to the standard Skyrme effective interaction has been widely considered in the past. Such a term has been shown to appear in the next-to-next-to-leading order of the Skyrme pseudo-potential. The aim of the present article is to provide the necessary tools to incorporate this term in a fitting procedure: first, a mean-field equation written in spherical symmetry in order to describe spherical nuclei and second, the response function to detect unphysical instabilities. With these tools it will be possible to build a new fitting procedure to determine the coupling constants of the new functional.
|
Becker, P., Davesne, D., Meyer, J., Navarro, J., & Pastore, A. (2017). Solution of Hartree-Fock-Bogoliubov equations and fitting procedure using the N2LO Skyrme pseudopotential in spherical symmetry. Phys. Rev. C, 96(4), 044330–17pp.
Abstract: We present the development of the extended Skyrme N2LO pseudopotential in the case of spherical even-even nuclei calculations. The energy density functional is first presented. Then we derive the mean-field equations and discuss the numerical method used to solve the resulting fourth-order differential equation together with the behavior of the solutions at the origin. Finally, a fitting procedure for such an N2LO interaction is discussed and we provide a first parametrization. Typical ground-state observables are calculated and compared against experimental data.
|