Nuclear energy density functional from chiral pion nucleon dynamics revisited

作者：Kaiser N^*; Weise W

来源：Nuclear Physics A, 2010, 836(3-4): 256-274.

DOI：10.1016/j.nuclphysa.2010.02.004

• Nuclear energy density functional
• Density-matrix expansion
• Chiral pion-nucleon dynamics

We use a recently improved density-matrix expansion to calculate the nuclear energy density functional in the framework of in-medium chiral perturbation theory. Our calculation treats systematically the effects from 1 pi-exchange, iterated 1 pi-exchange, and irreducible 2 pi-exchange with intermediate Delta-isobar excitations, including Pauli-blocking corrections up to three-loop order. We find that the effective nucleon mass M*(rho) entering the energy density functional is identical to the one of Fermi-liquid theory when employing the improved density-matrix expansion. The strength F(del)(rho) of the ((del) over bar rho)(2) surface-term as provided by the pion-exchange dynamics is in good agreement with that of phenomenological Skyrme forces in the density region rho(0)/2 < rho < rho(0). The spin-orbit coupling strength F(so)(rho) receives contributions from iterated 1 pi-exchange (of the "wrong sign") and from three-nucleon interactions mediated by 2 pi-exchange with virtual Delta-excitation (of the "correct sign"). In the region around rho(0)/2 similar or equal to 0.08 fm(-3) where the spin-orbit interaction in nuclei gains most of its weight these two components tend to cancel, thus leaving all room for the short-range spin-orbit interaction. The strength function F(J)(rho) multiplying the square of the spin-orbit density comes out much larger than in phenomenological Skyrme forces and it has a pronounced density dependence.

• 出版日期2010-5-15