Relativistic $O(q^4)$ two-pion exchange nucleon-nucleon potential:   parametrized version
  The chiral two-pion exchange nucleon-nucleon interaction has nowadays a rather firm conceptual basis, but depends on low-energy constants, which may be extracted from fits to data. In order to facilitate this kind of application, we present here a parametrized version of our relativistic expansion of this component of the force to $O(q^4)$, performed recently. 
R. Higa (Jefferson Lab), M. R. Robilotta (U. of Sao Paulo), C. A. da   Rocha (Sao Judas Tadeu U.)