Sf. Gao et al., BOSONIZATION IN THE PRESENCE OF CONFINEMENT - CALCULATION OF THE NUCLEON-NUCLEON INTERACTION, Physical review. C. Nuclear physics, 53(4), 1996, pp. 1936-1944
We describe an extended version of the Nambu-Jona-Lasinio (NJL) model
that includes a description of confinement. It is necessary to incorpo
rate some description of confinement in order to discuss the propertie
s of the sigma, rho, and omega mesons in the NJL model. These mesons,
in addition to the pion, are the minimum needed to describe the salien
t features of the nucleon-nucleon interaction. In previous work we con
sidered the relation between the bosonized NJL model and the one-boson
-exchange (OBE) model of the nucleon-nucleon force. Most of our attent
ion was given to pion and sigma exchange. We provide a review of that
work and extend our discussion to a consideration of rho and omega exc
hange. We also present a more detailed discussion of the bosonization
procedure. Our results depend upon the strength of the confining inter
action. Once that is fixed, we obtain good values for the omega-nucleo
n coupling constant, G(omega NN), and for the tensor coupling constant
f(r)ho, in the rho-nucleon interaction. (One limitation of the presen
t version of the model is that the ratio f(rho)/g(rho)=3.70, instead o
f the empirical value of f(rho)/g(rho)similar or equal to 6.1.) If we
consider nucleon-nucleon scattering for relatively small momentum tran
sfer, we obtain good results for the processes of sigma, pion, rho, an
d omega exchange. Remarkably, the description of pion exchange is very
accurate up to q(2) similar to-2 GeV2. That is, the microscopic model
reproduces the pion-exchange amplitude of the boson-exchange model ov
er a broad range of momentum transfer when we specify a single paramet
er than governs the momentum-transfer dependence of the pseudoscalar-i
sovector form factor of the nucleon. In the other channels (sigma,rho,
omega), the nucleon form factors may be treated in the same manner. Ho
wever, if we calculate the form factors in our model, we find that the
y are too ''soft'' to fit the OBE amplitudes away from q(2) similar or
equal to 0. Further work is needed to obtain good fits for the variou
s amplitudes for large momentum transfer, although the OBE amplitudes
are well reproduced in the case of scattering at small momentum transf
er (\q(2)\less than or equal to 0.1 GeV2).