Core-crust transition and crustal fraction of moment of inertia in neutron stars

Abstract

The crustal fraction of moment of inertia in neutron stars is calculated using $β$-equilibrated nuclear matter obtained from density dependent M3Y effective interaction. The transition density, pressure and proton fraction at the inner edge separating the liquid core from the solid crust of the neutron stars determined from the thermodynamic stability conditions are found to be $ρ_t=$ 0.0938 fm$^{-3}$, P$_t=$ 0.5006 MeV fm$^{-3}$ and $x_{p(t)}=$ 0.0308, respectively. The crustal fraction of the moment of inertia can be extracted from studying pulsar glitches and is most sensitive to the pressure as well as density at the transition from the crust to the core. These results for pressure and density at core-crust transition together with the observed minimum crustal fraction of the total moment of inertia provide a new limit for the radius of the Vela pulsar: $R \geq 4.10 + 3.36 M/M_\odot$ kms.

6 pages including 2 figures and 3 tables; Calculations are made more accurate by using very accurate values of Solar mass, erg to MeV conversion factor, pi and gravitational constant G. arXiv admin note: substantial text overlap with arXiv:1406.5302; text overlap with arXiv:hep-ph/0009357, arXiv:hep-ph/0011333, arXiv:hep-ph/0109135, arXiv:hep-ph/0102047 by other authors