Nuclear symmetry energy and the role of the tensor force, I. Vidana, University of Coimbra, Portugal − Using the Hellmann--Feynman theorem we analyze the contribution of the different terms of the nucleon-nucleon interaction to the nuclear symmetry energy E_sym and the slope parameter L.  The analysis is performed within the microscopic Brueckner--Hartree--Fock approach using the Argonne V18 potential plus the Urbana IX three-body force.  We find that the main contribution to E_sym and L comes from the tensor component of the nuclear force.