R-mode instability of neutron stars: LOCV approach

In this work, we study the r-mode instability of neutron stars and present critical angular velocity [Formula: see text] associated with bulk and shear viscosity for rotational stellar models. For this aim, we employ the lowest order constrained variational method and utilize realistic nucleon-nucleon interactions to determine the equation of state of neutron stars. We work within the framework of the slow rotation approximation and use various equations of state to calculate the angular velocity, fiducial gravitational radiation timescale and the rates of frequency change for both the maximum mass configuration and 1.4[Formula: see text][Formula: see text] stars. Additionally, we compute the equation of state of magnetized neutron matter and investigate the effects of strong magnetic field on the r-mode instability window. In addition, we examine the influence of neuron star crust on a star’s angular velocity.