Octet baryon electromagnetic form factors in nuclear medium

TL;DR

This paper investigates how octet baryon electromagnetic form factors are altered in nuclear matter using a covariant spectator quark model, revealing enhancements in magnetic form factors and variations in electric form factors, with implications for bound nucleons.

Contribution

The study extends the covariant spectator quark model to nuclear matter, incorporating hadron mass changes and pion-baryon coupling modifications to analyze baryon form factors.

Findings

Magnetic form factors are enhanced at low Q^2 in nuclear matter.

Electric form factors vary more rapidly with Q^2 in nuclear medium.

Predictions for neutron form factor modifications are provided.

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 $Q^2$ region, while the electric form factors show a more rapid variation with $Q^2$. 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.