出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：Wigner and Serber symmetries for the two-nucleon system provide unique examples of long distance
symmetries in Nuclear Physics, i.e. symmetries of the meson exchange forces broken only
at arbitrarily small distances. We analyze the large Nc picture as a key ingredient to understand
these, so far accidental, symmetries from a more fundamental viewpoint. A set of sum rules for
NN phase-shifts, NN potentials and coarse grained Vlowk NN potentials can be derived showing
Wigner SU(4) and Serber symmetries not to be fully compatible everywhere. The symmetry
breaking pattern found from the partial wave analysis data, high quality potentials in coordinate
space at long distances and their Vlowk relatives is analyzed on the light of large Nc contracted
SU(4)C symmetry. Our results suggest using large Nc potentials as long distance ones for the
two-nucleon system where the meson exchange potential picture is justified and known to be consistent
with large Nc counting rules. We also show that potentials based on chiral expansions do
not embody theWigner and Serber symmetries nor do they scale properly with Nc. We implement
the One Boson Exchange potential realization saturated with their leading Nc contributions due
to p,s ,r and w mesons. The short distance 1/r3 singularities stemming from the tensor force
can be handled by renormalization of the Schrödinger equation. A good description of deuteron
properties and deuteron electromagnetic form factors in the impulse approximation for realistic
values of the meson-nucleon couplings is achieved.
