Initial Configuration

Both stars obey a n = 1 polytropic equation of state, P=Kρ₀^Γ, at t = 0. They are evolved according to the adiabatic law, P=(Γ-1)ρ₀ε. Here P is the pressure, K the polytropic gas constant, Γ is the adiabatic index, &epsilon is the specific internal energy, and ρ₀ is the rest-mass density. We chose Γ = 2 to mimick stiff nuclear matter. Both stars are irrotational (nonspinning) and are in a quasiequilibrium circular orbit.

We consider three different NSNS binaries:

• M1414 - identical low-mass stars each with compaction (M/R)_∞ = 0.14 and nondimensional rest mass M₀ = 0.146.


• M1616 - identical high-mass stars each with compaction (M/R)_∞ = 0.16 and nondimensional rest mass M₀ = 0.160.


• M1418 - stars with compactions (M/R)_∞ = 0.14 and 0.18 and nondimensional rest masses M₀ = 0.146 and 0.171.

With the adopted equation of state, the maximum nondimensional rest mass for an isolated, spherical star is M₀ = 0.180.

last updated 1 Mar. 09 by TC