Related papers: Heavy hybrid stars from multi-quark interactions
We examine the properties of composite octet baryons in the nuclear medium and neutron star matter. The internal quark-diquark structure of the octet baryons and the equations of state of nuclear matter and neutron star matter in the mean…
We study the possible existence of deconfined quark matter in the interior of neutron stars using the Nambu-Jona-Lasinio model to describe the quark phase. We find that typical neutron stars with masses around 1.4 solar masses do not…
We study the effects of heavy quarks on the equation of state for cold and dense quark matter obtained from perturbative QCD, yielding observables parametrized only by the renormalization scale. We investigate the thermodynamics of charm…
Using a density dependent quark model and a relativistic model within the mean-field approximation for hadrons with density dependent meson-baryon couplings, we construct, for the first time, models that describe hybrid neutron stars…
In this paper we use the equation of state (EOS) of 2+1 flavors Nambu-Jona-Lasinio (NJL) model to study the structure of compact stars. To avoid the ultraviolet divergence, we employ the proper-time regularization (PTR) with an ultraviolet…
Densities in compact stars may be such that quarks are no longer confined in hadrons, but instead behave as weakly interacting particles. In this regime perturbative calculations are possible. Yet, due to high pressures and an attractive…
In this work we present a study of magnetars composed of hadronic and quark matter, under the influence of strong magnetic fields. We present our results for hadronic matter taking into account the effects that the inclusion of anomalous…
We investigate a nonlocal chiral quark model with separable 4-fermion interaction for the case of U(3) flavor symmetry and show that strange quark matter is unlikely to occur in a large enough volume of a compact star to entail remarkable…
Effects of the vector-type four-quark interaction on QCD phase structure are investigated in the imaginary chemical potential region, by using the Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model with the extended Z3 symmetry. In the…
We study the equation of state of neutron-star matter including the effects of isovector-vector coupling in quark matter. We employ the relativistic mean-field theory with an extended TM1 parameter set to describe hadronic matter and the…
Hadron--quark mixed phase is expected in a wide region of the inner structure of hybrid stars. However, we show that the hadron--quark mixed phase should be restricted to a narrower region to because of the charge screening effect. The…
Recently, with the goal to study multiplicity of chemically peculiar stars, we carried out a survey of 40 stars using diffraction limited near infrared (IR) imaging with NAOS-CONICA (NACO) at the VLT. Here, we announce the detection of 27…
We study the instabilities of quark matter in the framework of a generalized Nambu--Jona-Lasinio model, in order to explore possible competition between three-quark clustering to form nucleons and diquark formation leading to color…
We have investigated shear viscosity of quark matter in presence of a strong uniform magnetic field background where Nambu-Jona-Lasinio model has been considered to describe the magneto-thermodynamical properties of the medium. In presence…
Recently, it has been shown that the standard Nambu-Jona-Lasinio (NJL) model is not able to reproduce the correct QCD behavior of the gap equation at large density, and therefore a different cutoff procedure at large momenta has ben…
We study the so called hybrid stars, which are hadronic stars that contain a core of deconfined quarks. For this purpose, we make use of an extended version of the SU(3) chiral model. Within this approach, the degrees of freedom change…
The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) studies properties and phase transitions of nuclear matter in various nucleus-nucleus collisions at center-of-mass energies per nucleon collision $\sqrt{s_{NN}}=7.7$-200 GeV.…
We study the hadron-quark phase transition in the interior of neutron stars. The relativistic mean field (RMF) theory is adopted to describe the hadronic matter phase, while the Nambu-Jona-Lasinio (NJL) model is used for the quark matter…
In the present work we are interested in understanding various properties of quark matter subject to strong magnetic fields described by the Nambu-Jona-Lasinio model with Polyakov loop. We start by analysing the differences arising from two…
It is shown that eight-quark interactions, which are needed to stabilize the ground state of the combined three flavor Nambu -- Jona-Lasinio and 't Hooft Lagrangians, play also an important role in determining the critical temperature at…