the linear adiabatic pulsation-periods of mira variable stars have been derived. approximately 2701[1]models were calculated for m = 0.7 mθ to 2 mθ stars with radii from 180 rθ to 340 rθ and luminosities from 2800 lθ to 10,000 lθ. the chemical composition of all models is (x,z) = (0.7,0.02). from the result of this study, linear relations on luminosity-period-mass relationship and luminosity-pe...

We study local stability of self-gravitating fluid and stellar disk in the context of modified gravity theories which predict a Yukawa-like term in the gravitational potential of a point mass. We investigate the effect of such a Yukawa-like term on the dynamics of self-gravitating disks. More specifically, we investigate the consequences of the presence of this term for the local stability of t...

In this work, we investigate the influence of phase transition and a stiffer fluid in neutron stars' cores on static equilibrium configuration, dynamical stability, tidal deformability. For aim, it is taken into account that core envelope follow relativistic polytropic equation state. We find will reflect total mass, radius, speed sound, radial stability with slow rapid conversion at interface,...

The merger of two neutron stars leaves behind a rapidly spinning hypermassive object whose survival is believed to depend on the maximum mass supported by the nuclear equation of state, angular momentum redistribution by (magneto-)rotational instabilities, and spindown by gravitational waves. The high temperatures (∼5 − 40MeV) prevailing in the merger remnant may provide thermal pressure suppor...

Aims. We calculate the energy release associated with a strong first-order phase transition, from normal phase N to an “exotic” superdense phase S, in a rotating neutron star. Such a phase transition N−→S, accompanied by a density jump ρ N −→ ρ S , is characterized by ρ S /ρ N > 3 2 (1+P0/ρNc ), where P0 is the pressure, at which phase transition occurs. Configurations with small S-phase cores ...

the linear adiabatic pulsation-periods of mira variable stars have been derived. approximately 2701[1]models were calculated for m = 0.7 mθ to 2 mθ stars with radii from 180 rθ to 340 rθ and luminosities from 2800 lθ to 10,000 lθ. the chemical composition of all models is (x,z) = (0.7,0.02). from the result of this study, linear relations on luminosity-period-mass relationship and luminosity-pe...