Gravitational wave content and stability of uniformly, rotating, triaxial neutron stars in general relativity
Targets for ground-based gravitational wave interferometers include continuous, quasiperiodic sources of gravitational radiation, such as isolated, spinning neutron stars. In this work, we perform evolution simulations of uniformly rotating, triaxially deformed stars, the compressible analogs in general relativity of incompressible, Newtonian Jacobi ellipsoids. We investigate their stability and gravitational wave emission. We employ five models, both normal and supramassive, and track their evolution with different grid setups and resolutions, as well as with two different evolution codes. We find that all models are dynamically stable and produce a strain that is approximately one-tenth the average value of a merging binary system. We track their secular evolution and find that all our stars evolve toward axisymmetry, maintaining their uniform rotation, rotational kinetic energy, and angular momentum profiles while losing their triaxiality.
Tsokaros, Antonios Ruiz Meneses, Milton Javier Paschalidis, Vasileios Shapiro, Stuart L. Baiotti, Luca Uryū, Kōji 2017 Gravitational wave content and stability of uniformly, rotating, triaxial neutron stars in general relativity Physical Review D 95 12 1 14