Correlation between the symmetry energy slope and the deconfinement phase transition

We study how the nuclear symmetry energy slope ($L$) can affect the hadron-quark phase transition and neutron star properties. We show that the main physical quantities as the critical chemical potential and pressure are strongly influenced by the symmetry energy slope. In extreme cases, the total amount of deconfined quarks can reach up to $99\%$ of the hybrid star mass.

Figure 1

Critical chemical potential (a) and pressure (b) as a function of the symmetry energy slope $L$, for different quark-meson couplings: $G_V=0.38$, 0.40, and 0.42 ${\mathrm{fm}}^2$.

Figure 2

Hybrid EoS for different slope values of the hadron phase and for quark vector couplings $G_V=0.38$ (a) and 0.42 ${\mathrm{fm}}^2$ (b) in the top and bottom figures, respectively.

Figure 3

Energy difference (a) and latent energy (b) of the deconfinement transition as a function of the slope. Each curve corresponds to a different quark meson coupling, $G_V=0.38$, 0.40, and 0.42 ${\mathrm{fm}}^2$.

Figure 4

Mass radius diagram for hybrid stars within $G_V=0.38$ (a) and $G_V=0.42{\mathrm{fm}}^2$ (b). Different curves represent different slope values for hadron matter. The hatched areas are the constraints coming from the PSR $\mathrm{J}0740+6620$ [50] and the radius of the canonical star as discussed in the text.

Figure 5

Percentual amount of quarks in the core of the most massive hybrid stars. The amount of quarks can be as high as $99\%$ of the total mass of the star.