Related papers: Solid Quark Stars?
We show that within a recently developed nonlocal chiral quark model the critical density for a phase transition to color superconducting quark matter under neutron star conditions can be low enough for these phases to occur in compact star…
Strange-quark matter (SQM) is a likely candidate of the ground state of nuclear matter. Along with many other equations of state (EoSs), SQM seemed to be severely constrained by the recent discoveries of the 1.97 $M_\odot$ PSR J1614-2230…
If quark matter is energetically favored over nuclear matter at zero temperature and pressure then it has long been expected to take the form of strange quark matter (SQM), with comparable amounts of $u$, $d$, $s$ quarks. The possibility of…
Heavy-quark effects on the equation of state for cold and dense quark matter are obtained from perturbative QCD, yielding observables parametrized only by the renormalization scale. In particular, we investigate the thermodynamics of charm…
In the context of the standard model of particle physics, there is a definite upper limit to the density of stable compact stars. However, if there is a deeper layer of constituents, below that of quarks and leptons, stability may be…
At very large densities and/or temperatures a quark-hadron phase transition is expected to take place. Simulations of QCD on lattice at zero baryon density indicate that the transition occurs at $T_c \sim 150-170$ MeV. The calculations…
The appearance of quark matter in the core of hybrid stars is a fundamental issue in such compact stars. The central density of these stars is sufficiently high such that nuclear matter undergoes a further change into other exotic phases…
The possibility of strange stars mixed with dark energy to be one of the candidates for dark energy stars is the main issue of the present study. Our investigation shows that quark matter acts as dark energy after a certain yet unknown…
Neutron stars contain matter in one of the densest forms found in the Universe. This feature, together with the unprecedented progress in observational astrophysics, makes such stars superb astrophysical laboratories for a broad range of…
It has recently been pointed out that if the surface tension of quark matter is low enough, the surface of a strange star will be a crust consisting of a crystal of charged strangelets in a neutralizing background of electrons. This affects…
It is conventionally thought that the state equation of dense matter softens and thus cannot result in high maximum mass if pulsars are quark stars, and that a recently discovered $2M_\odot$ pulsar (PSR J1614-2230) may make quark stars to…
The chemical evolution of nascent quark matter core in a newborn compact neutron star is studied in presence of a strong magnetic field. The effective rate of strange quark production in degenerate quark matter core in presence of strong…
We investigated compact stars consisting of cold quark matter and fermionic dark matter treated as two admixed fluids. We computed the stellar structures and fundamental radial oscillation frequencies for different masses of the dark…
The cooling of a young bare strange star is studied numerically by solving the equations of energy conservation and heat transport for both normal and superconducting strange quark matter inside the star. We show that the thermal luminosity…
Recent Chandra observations have raised expectations that the objects RX J185635-3754 and 3C58 are either bare strange quark stars or stars with extended quark cores. However, these observations can also be interpreted in terms of normal…
The previous thermodynamic treatment for models with density and/or temperature dependent quark masses is shown to be inconsistent with the requirement of fundamental thermodynamics. We therefore study a fully self-consistent one according…
The densest predicted state of matter is colour-superconducting quark matter, in which quarks near the Fermi surface form a condensate of Cooper pairs. This form of matter may well exist in the core of compact stars, and the search for…
After a brief non technical introduction of the basic properties of strange quark matter (SQM) in compact stars, we consider some of the late important advances in the field, and discuss some recent astrophysical observational data that…
Pulsar-like compact stars usually have strong magnetic fields, with the strength from $\sim 10^8$ to $\sim 10^{12}$ Gauss on surface. How such strong magnetic fields can be generated and maintained is still an unsolved problem, which is, in…
One of the most important questions in the study of compact objects is the nature of pulsars, including whether they consist of neutron matter or strange quark matter (SQM). However, few mechanisms for distinguishing between these two…