Non-perturbative methods for NN singular interactions
Grupo de Física Nuclear e IUFFyM, Universidad de Salamanca, 37008, Salamanca, Spain
2 Departamento de Física, Universidad de Murcia, 30071, Murcia, Spain
Accepted: 17 March 2021
Published online: 6 June 2021
Chiral Effective Field Theory (EFT) has been extensively used to study the NN interaction during the last three decades. In Effective Field Theories (EFTs) the renormalization is performed order by order including the necessary counter terms. Due to the strong character of the NN interaction a non-perturbative resummation is needed. In this work, we will review some of the methods proposed to completely remove cut-off dependencies. The methods covered are renormalization with boundary conditions, renormalization with one counter term in momentum space (or equivalently subtractive renormalization) and the exact N/D method. The equivalence between the methods up to one renormalization condition will be checked showing results in the NN system. The exact N/D method allows to go beyond the others, and using a toy model it is shown how it can renormalize singular repulsive interactions.
© The Author(s), under exclusive licence to EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature 2021