Octet baryon electromagnetic form factors in nuclear medium

Abstract

We study the octet baryon electromagnetic form factors in nuclear matter using the covariant spectator quark model extended to the nuclear matter regime. The parameters of the model in vacuum are fixed by the study of the octet baryon electromagnetic form factors. In nuclear matter the changes in hadron properties are calculated by including the relevant hadron masses and the modification of the pion–baryon coupling constants calculated in the quark–meson coupling model. In nuclear matter the magnetic form factors of the octet baryons are enhanced in the low Q² region, while the electric form factors show a more rapid variation with Q². The results are compared with the modification of the bound proton electromagnetic form factors observed at Jefferson Lab. In addition, the corresponding changes for the bound neutron are predicted.