$D$ mesons in strongly magnetized asymmetric nuclear matter

The medium modifications of the open charm mesons ($D$ and $\overline{D}$) are studied in isospin asymmetric nuclear matter in the presence of strong magnetic fields, using a chiral effective model. The mass modifications of these mesons in the effective hadronic model arise due to their interactions with the protons, neutrons, and the scalar mesons (nonstrange isoscalar, $\sigma$, strange isoscalar, $\zeta$, and nonstrange isovector, $\delta$) in the magnetized nuclear matter. In the presence of a magnetic field, for the charged baryon, i.e., the proton, the number density as well as the scalar density have contributions due to the summation over the Landau energy levels. For given values of the baryon density and isospin asymmetry, the scalar fields are solved self-consistently from their coupled equations of motion. The modifications of the masses of the $D$ and $\overline{D}$ mesons are calculated from the medium modifications of the scalar fields and the nucleons. The effects of the anomalous magnetic moments of the nucleons on the masses of the open charm mesons are also investigated in the present work. The effects of isospin asymmetry as well as of the anomalous magnetic moments are observed to be prominent at high densities for large values of magnetic fields.

Figure 1

The scalar field $\sigma$ plotted as function of the baryon density ${\rho }_B/{\rho }_0$, for different values of magnetic field, is shown for different values of the isospin asymmetry parameter $\eta$, when the effects of anomalous magnetic moment are taken into account, and compared to the case when the effects of anomalous magnetic moment are not taken into account (dotted line).

Figure 2

The scalar field $\zeta$ plotted as function of the baryon density ${\rho }_B/{\rho }_0$, for different values of magnetic field, is shown for different values of the isospin asymmetry parameter $\eta$, when the effects of anomalous magnetic moment are taken into account, and compared to the case when the effects of anomalous magnetic moment are not taken into account (dotted line).

Figure 3

The scalar field $\delta$ plotted as function of the baryon density ${\rho }_B/{\rho }_0$, for different values of magnetic field, is shown for different values of the isospin asymmetry parameter $\eta$ when the effects of anomalous magnetic moment are taken into account, and compared to the case when the effects of anomalous magnetic moment are not taken into account (dotted line).

Figure 4

The effective masses of $D$ ($D^{+},D^0$) and $\overline{D}$ ($D^{-},\overline{D^0}$) mesons in MeV plotted as functions of $eB/m_{\pi }^2$, for baryon density ${\rho }_B={\rho }_0$, with different values of isospin asymmetry parameter $\eta$, accounting for the effects of the anomalous magnetic moments (AMMs) for the nucleons. The results are compared with the case of not accounting for the anomalous magnetic moments (shown as dotted lines).

Figure 5

The effective masses of $D$ ($D^{+},D^0$) and $\overline{D}$ ($D^{-},\overline{D^0}$) mesons in MeV plotted as functions of $eB/m_{\pi }^2$, for baryon density ${\rho }_B=3{\rho }_0$, with different values of isospin asymmetry parameter $\eta$, accounting for the effects of the anomalous magnetic moments (AMMs) for the nucleons. The results are compared with the case of not accounting for the anomalous magnetic moments (shown as dotted lines).

Figure 6

The effective masses of $D$ ($D^{+},D^0$) and $\overline{D}$ ($D^{-},\overline{D^0}$) mesons in MeV plotted as functions of $eB/m_{\pi }^2$, for baryon density ${\rho }_B=5{\rho }_0$, with different values of isospin asymmetry parameter $\eta$, accounting for the effects of the anomalous magnetic moments (AMMs) for the nucleons. The results are compared with the case of not accounting for the anomalous magnetic moments (shown as dotted lines).