Phenomenological neutron star equations of state: 3-window modeling of QCD matter

Understand

We discuss the 3-window modeling of cold, dense QCD matter equations of state at density relevant to neutron star properties.

• At low baryon density, n_B < ~ 2n_s (n_s: nuclear saturation density), we utilize purely hadronic equations of state that are constrained by empirical observations at density n_B ~ n_s and neutron star radii.
• At high density, n_B > ~ 5n_s, we use the percolated quark matter equations of state which must be very stiff to pass the two-solar mass constraints.
• The intermediate domain at 2 < n_B/n_s < 5 is described as neither purely hadronic nor percolated quark matter, and the equations of state are inferred by interpolating hadronic and percolated quark matter equations of state.