Moon Taeg Jeong

Nucleon Electromagnetic Properties Modified in Nuclear Medium

Introducing effective masses of mesons and nucleons in the framework of the cloudy bag model, we calculated the bound nucleon form factors, magnetic moments, rms radii and axial coupling constant. These form factors have been applied to evaluate the dynamical charge longitudinal structure factors and the sum rules of nuclear response functions.

Investigation of electromagnetic form factors for light nuclei

Abstract Transverse form factors for electron scattering from 6 Li and 9 Be have been calculated with the Cohen-Kurath wave functions, by using the phenomenological magnetic form factors of bound nucleons. The effects of meson exchange currents on the EM form factors were also investigated.

The Electric Dipole Amplitudes of the Neutral Pion Photoproduction on the Proton near Threshold

The electric dipole amplitude E 0+ for p (γ, π 0 ) p near threshold has been extracted from the experimental data by fitting the total cross section in high energy region, E γ >160 MeV. The result is (-1.56±0.10)×10 -3 m π+ -1 . This amplitude is calculated by taking the vector mesons into account in the pole model of t-channel. Our analysis manifests a favor of negative sign for the ρπγ coupling constant.

Electron scattering and pion photoproduction on the trinucleon

The electromagnetic form factors and pion photoproduction on the trinucleon have been calculated using mesons (π, ρ, ω) and baryons ( N , Δ) properties modified by the presence of the nuclear medium. It is shown that use of their modified masses and coupling constants brings the positions of the first minimum for the trinucleon electromagnetic form factors to a little lower values of momentum transfer Q 2 and improves considerably the theoretical results in the region of high momentum transfers. The pion photoproduction on the trinucleon are consistently evaluated with mesons and baryons properties modified in the nuclear medium.