Examination of the influence of the $f_0\left(975\right)$ and $\varphi$(1020) mesons on the surface gravitational redshift of the neutron star PSR J0348+0432

The effect of the mesons $f_0\left(975\right)$ and $\varphi \left(1020\right)$ on the surface gravitational redshift of the neutron star PSR J0348+0432 is examined in the framework of the relativistic mean field theory by choosing the suitable hyperon coupling constants. We find that compared with that without considering the mesons $f_0\left(975\right)$ and $\varphi \left(1020\right)$, the value range of the radius $R$ of the neutron star PSR J0348+0432 would be changed from a narrow range 12.964 km $\sim 12.364$ km to a wider range 12.941 km $\sim 11.907$ km corresponding to the observation mass $M=1.97M_{\odot }\sim 2.05M_{\odot }$. We also find that the value range of the surface gravitational redshift $z$ of the neutron star PSR J0348+0432 changes from 0.3469 $\sim 0.3997$ to 0.3480 $\sim 0.4263$ corresponding to the observation mass $M=1.97M_{\odot }\sim 2.05M_{\odot }$ with the mesons $f_0\left(975\right)$ and $\varphi \left(1020\right)$ being considered. This means that the radius $R$ and the surface gravitational redshift $z$ both will be constrained in a wider scope with the mesons $f_0\left(975\right)$ and $\varphi \left(1020\right)$ being considered. We also can see that the difference of the radius and the surface gravitational redshift is not so large whether the mesons $f_0\left(975\right)$ and $\varphi \left(1020\right)$ are considered or not. This indicates that the mesons $f_0\left(975\right)$ and $\varphi \left(1020\right)$ do not play a major role in the massive neutron star PSR J0348+0432.

Figure 1

The mass of the neutron star as a function of the parameters number.

Figure 2

The radius of the neutron star as a function of the mass. Case 1 does not include the mesons $f_0\left(975\right)$ and $\varphi \left(1020\right)$ while case 2 includes them.

Figure 3

The radius of the neutron star as a function of the mass. Case 1 does not include the mesons $f_0\left(975\right)$ and $\varphi \left(1020\right)$ while case 2 includes them.