Related papers: On the maximum rotational frequency of neutron and…
We study effects of the strange quark mass and of the QCD coupling constant in the MIT bag model of quark matter with lowest order quark-gluon interactions on the rapid rotation of strange stars. The influence of rotation on global…
We report on numerical calculations of orbital and epicyclic frequencies in nearly circular orbits around rotating neutron stars and strange quark stars. The FPS equation of state was used to describe the neutron star structure while the…
Using the most recent realistic effective interactions for nuclear matter with a smooth extrapolation to high densities including causality, we constrain the equation of state and calculate maximum masses of rotating neutron stars. First…
We have considered a hot neutron star with a quark core, a mixed phase of quark-hadron matter, and a hadronic matter crust and have determined the equation of state of the hadronic phase and the quark phase, we have then found the equation…
We make a first calculation of eigenfrequencies of radial pulsations of neutron stars with quark cores in a general relativistic formalism given by Chandrasekhar. The equations of state (EOS) used to estimate such eigenfrequencies have been…
The recent precise measurement of the mass of pulsar PSR J1614$-$2230, as well as observational indications of even more massive neutron stars, has revived the question of the composition of matter at the high densities prevailing inside…
We study the hadron-quark phase transition in the interior of neutron stars (NS's). We calculate the equation of state (EOS) of hadronic matter using the Brueckner-Bethe-Goldstone formalism with realistic two-body and three-body forces, as…
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…
The existence of quark matter inside the heaviest neutron stars has been the topic of numerous recent studies, many of them suggesting that a phase transition to strongly interacting conformal matter inside neutron stars is feasible. Here…
Chiral Lagrangian and quark-meson coupling models of hyperon matter are used to estimate the maximum mass of neutron stars. Our relativistic calculations include, for the first time, both Hartree and Fock contributions in a consistent…
It has been suggested that observations of quasi periodic oscillations (QPOs) in the X-ray fluxes from low mass X-ray binaries can be used to constrain the mass of the compact object and the equation of state of its matter. A specific…
We investigate the properties of the neutron star with relativistic mean field models. We incorporate in the quantum hadrodynamics and in the quark-meson coupling models a possible reduction of meson masses in nuclear matter. The equation…
Strange quark matter in beta equilibrium at high densities is studied in a quark confinement model. Two equations of state are dynamically generated for the {\it same} set of model parameters used to describe the nucleon: one corresponds to…
We study the properties of strange quark matter in equilibrium with normal nuclear matter. Instead of using the conventional bag model in quark sector, we achieve the confinement by a density-dependent quark mass derived from in-medium…
The recent measurements of the masses of the pulsars PSR J1614-2230 and PSR J0348-0432 provide independent proof for the existence of neutron stars with masses in range of 2 $M_\odot$. This fact has significant implications for the physics…
Rapid uniformly-rotating neutron stars are expected to be formed for instance in the collapse of some massive stars, the accretion of compact object binaries, and double neutron star mergers. The huge amount of the rotational energy has…
We study the properties of neutron stars adopting relativistic equations of state of neutron star matter, calculated in the framework of the relativistic Brueckner-Hartree-Fock approximation for electrically charge neutral neutron star…
In the present work we use the vector MIT bag model to describe quark matter and obtain the macroscopic properties of neutron stars. We also calculate the speed of sound of quark matter described by this model with specific parameter values…
We study the radial pulsation frequencies of slowly rotating neutron stars in general relativistic formalism using realistic equations of state. It is found that the pulsation frequencies are always an increasing function of rotation rate.…
We study the orbital and epicyclic frequencies of particles orbiting around rapidly rotating neutron stars and strange stars in a particular scalar-tensor theory of gravity. We find very large deviations of these frequencies, when compared…