A new view on the maximum mass of differentially rotating neutron stars

Understand

We study the main astrophysical properties of differentially rotating neutron stars described as stationary and axisymmetric configurations of a moderately stiff $\Gamma=2$ polytropic fluid.

• The high level of accuracy and of stability of our relativistic multidomain pseudo-spectral code enables us to explore the whole solution space for broad ranges of the degree of differential rotation, but also of the stellar density and oblateness.
• Staying within an astrophysicaly motivated range of rotation profiles, we investigate the characteristics of neutron stars with maximal mass for all types of families of differentially rotating relativistic objects identified in a previous article Ansorg, Gondek-Rosinsla, Villain (2009).
• We find that the maximum mass depends on both the degree of differential rotation and on the type of solution.