Nowadays it has become customary in nuclear physics to denote by “tradition” the approach that considers nucleons and mesons as the relevant degrees of freedom. It is the purpose of this chapter to review this “traditional” approach in the area of nuclear forces and their applications to nuclear structure.

The Meson Theory of Nuclear Forces and Nuclear Structure

Charge symmetry, quarks and mesons

$\rho - \omega$ mixing, vector meson dominance and the pion form-factor

: Quasi-free proton-proton scattering in light nuclei was studied experimentally at 450 Mev incident proton energy. Energy aod angular correlations of the two emerging protons were measured using two double focusing magnetic spectrometers and a multi-channel electronic detector system.

Quasi-free proton-proton scattering in light nuclei at 450 mev

▪ Abstract Charge symmetry breaking (CSB) in the strong interaction occurs because of the difference between the masses of the up and down quarks. The use of effective field theories allows us to follow this influence of confined quarks in hadronic and nuclear systems. We review the progress in observing and understanding CSB, with particular attention to the recent successful observations of CSB in measurements involving the production of a single neutral pion, and to the related theoretical progress.

https://www.annualreviews.org/doi/pdf/10.1146/annurev.nucl.56.080805.140446

Charge Symmetry Breaking and QCD

An experiment resulting in the first measurement of the isospin-mixing, charge-symmetry violating component of the n-italic-p-italic interaction has been performed. The experiment determined the difference in the angles of the zero crossing of the neutron and proton analyzing powers A-italic/sub n-italic/ and A-italic/sub p-italic/ at 477 MeV. In terms of the laboratory scattering angle of the neutron, the measured difference t-italich-italice-italict-italica-italic/sub 0//sub n-italic/(A/sub n/)= -t-italich-italice-italict-italica-italic/sub 0//sub n-italic/(A/sub p/) = +0.13X(de +- 0.06 X(de( +- 0.03X(de) where the second error is a worst case estimate of systematic error. The resulting difference in the analyzing powers at the zero-crossing angle A-italic/sub n-italic/-A/sub p/ = +0.0037 +- 0.0017( +- 0 .0008).

/pdf/test-of-charge-symmetry-in-neutron-proton-elastic-scattering-4hg2dthpxk.pdf

Test of charge symmetry in neutron-proton elastic scattering at 477 MeV

Charge-symmetry breaking in np elastic scattering at 477 MeV.

Elastic scattering of polarized protons from 3He at intermediate energies.

Quasifree p-p and p-d scattering from $^{3}\mathrm{He}$ at intermediate energies has been studied. The $^{3}\mathrm{He}$(p,2p)d reaction has been measured at 300 MeV at the angle pair 70\ifmmode^\circ\else\textdegree\fi{}-33\ifmmode^\circ\else\textdegree\fi{} and at 450 MeV at the angle pairs 70\ifmmode^\circ\else\textdegree\fi{}-30\ifmmode^\circ\else\textdegree\fi{} and 46\ifmmode^\circ\else\textdegree\fi{}-46\ifmmode^\circ\else\textdegree\fi{} for recoil momenta between 350 and 530 MeV/c. For the $^{3}\mathrm{He}$(p,pd)p reaction, energy sharing loci have been measured at 300 MeV at the angle pair 70\ifmmode^\circ\else\textdegree\fi{}-33\ifmmode^\circ\else\textdegree\fi{} and at 450 MeV for the angle pairs 25\ifmmode^\circ\else\textdegree\fi{}-68\ifmmode^\circ\else\textdegree\fi{}, 50\ifmmode^\circ\else\textdegree\fi{}-68\ifmmode^\circ\else\textdegree\fi{}, and 70\ifmmode^\circ\else\textdegree\fi{}-30\ifmmode^\circ\else\textdegree\fi{}, yielding a recoil momentum range from 0 to 480 MeV/c. The spectral function S(q,E) with E equal to the two-body breakup energy for $^{3}\mathrm{He}$ has been deduced from the present results in the framework of the plane-wave impulse approximation as a function of the p-d relative momentum q. The spectral function is compared with other spectral functions obtained from previous $^{3}\mathrm{He}$(p,pd)p and $^{3}\mathrm{He}$(e,e'p)d experiments and with existing theoretical predictions.

H.P. Gubler

Papers

Test of charge symmetry in neutron-proton elastic scattering at 477 MeV

Charge-symmetry breaking in np elastic scattering at 477 MeV.

Elastic scattering of polarized protons from 3He at intermediate energies.

3He(p,2p)d and 3He(p,pd)p reactions at large recoil momenta.

Large angle 2H(p, 2p)n at 507 MeV