Speaker
Luca Girlanda
(Universita del Salento, Lecce & INFN-Lecce)
Description
Despite long-lasting efforts in the determination of a realistic three-nucleon force (TNF), none of the presently available models leads to a satisfactory description of bound and scattering states of the $A=3$ system. It seems natural to ascribe the above situation to the fact that these models include a very small number of adjustable parameters, compared to the two-nucleon interaction case. For example, in the framework of the chiral expansion, only 2 low-energy constants (LECs) enter up to and including N3LO. At the following order (N4LO) one encounters 10 additional LECs, which parametrize the short-range component of the TNF, and are unconstrained by chiral symmetry. As such, they could provide the necessary flexibility to arrive at a truly realistic model for the TNF. In this contribution we will report about our progress along these lines. In particular we examine to which extent the AV18 $NN$ interaction, supplemented by the leading and subleading contact-range TNF, provides a satisfactory fit to $N-d$ scattering data.
Primary author
Luca Girlanda
(Universita del Salento, Lecce & INFN-Lecce)
Co-authors
Dr
Alejandro Kievsky
(PI)
Dr
Michele Viviani
(PI)
