Comparison of quasifree (p,2p) with (p,pn) scattering as a check of the impulse approx

Abstract

It is shown that the ratio o f the cross sections o f quasifree (p ,Zp) and (p ,pn) reactions in complex nuclei for identical and suitable geometries can be reliably calculated in the distorted wave impulse approximation. A comparison with preliminary experimental results supports the validity of the impulse approximation for the medi um energy scattering of nucleons.

The quark-photon vertex and meson electromagnetic form factors

“…The details of the model can be found in Refs. [2,3]. It leads to chiral symmetry breaking and confinement; furthermore, at large momenta, our effective interaction reduces to the perturbative running coupling and thus preserves the one-loop renormalization group behavior of QCD and reproduces perturbative results in the ultraviolet region.…”

“…The Dyson-Schwinger equations [DSEs] form a useful tool for nonperturbative QCD modeling of hadrons and their interactions. They have been successfully applied to calculate properties of light vector and pseudoscalar mesons [1,2], as described elsewhere in these proceedings [3]. The dressed-quark propagator, as obtained from its DSE, together with the Bethe-Salpeter amplitude as obtained from the Bethe-Salpeter equation [BSE] for qq bound states, form essential ingredients for calculations of meson couplings and form factors [4].…”

“…Here, we use a solution of the DSE for the quark-photon vertex under the same truncation as used in Refs. [1][2][3] for light mesons.…”

“…It leads to chiral symmetry breaking and confinement; furthermore, at large momenta, our effective interaction reduces to the perturbative running coupling and thus preserves the one-loop renormalization group behavior of QCD and reproduces perturbative results in the ultraviolet region. The model gives a good description of the π, ρ, K, K ⋆ and φ masses and decay constants [2,3].…”

New insight into nuclear structure from QCD

“…In χPT the next term is non-analytic in m q [55]. However, over the relevant mass range, fits to lattice data, as well as fits to Schwinger-Dyson phenomenology [56,57] and a best fit to the χPT expansion, all suggest that…”