We study the structure of spherically symmetric and static objects in the presence of a nonminimally coupled scalar field having a potential of the form $V(ϕ)=-μ^2ϕ^2/2+λϕ^4/4$. We numerically solve equations of the system using two different realistic equations of state for neutron matter and give the mass-radius relations as well as the radial profiles of the scalar field, densities and the mass function for a sample configuration. We show that a specific solution type encountered in such systems causes characteristic neutron star mass-radius relations to turn into the ones belonging to strange quark stars.
We study the electromagnetic spectrum of accretion disks around neutron and strange stars in $\mathcal{R}^2$ gravity. Both static and rapidly rotating models are investigated. The results are compared with the General Relativistic results. We found difference between the results in both theories of about 50\% for the electromagnetic flux and about 20\% in the luminosity for models with equal mass and angular velocity in both theories. The observed differences are much lower for models rotating with Kelperian velocity and with equal masses.
In this article, we demonstrated a stellar model for compact star in presence of strange matter embedded in $D\ge4$ dimensional space-time defind by Finch-Skea metric. To study the relevant physical properties of the interior matter, we consider the equation of state $(henceforth~EOS)$ as proposed in MIT bag model given by $p=\frac{1}{3}(ρ-4B)$, where $B$ is termed as bag constant. The Mass-Radius relationships in four and higher dimensions are determined using the range of values of surface density through the relation $ρ_{s}=4B$ for which bulk strange matter may be a viable issue for compact…
Strangeness Transport in Binary Neutron Star Mergers
California Institute of Technology（加州理工学院）；KTH Royal Institute of Technology（皇家理工学院）；University of Southampton（南安普顿大学）；Walter Burke Institute for Theoretical Physics, California Institute of Technology（加州理工学院沃尔特·伯克理论物理研究所）；Illinois Center for Advanced Studies of the Universe, Department of Physics, University of Illinois at Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校物理系宇宙高级研究伊利诺伊中心）；Kent State University（肯特州立大学）
Rapidly and differentially rotating compact stars are believed to be formed in binary neutron star merger events, according to both numerical simulations and the multi-messenger observation of GW170817. The lifetime and evolution of such a differentially rotating star, is tightly related to the observations in the post-merger phase. Various studies on the maximum mass of differentially rotating neutron stars have been done in the past, most of which assume the so-called $j$-const law as the rotation profile inside the star and consider only neutron star equations of state. In this paper, we ex…
We investigate the properties of anisotropic, spherically symmetric compact stars, especially neutron stars and strange quark stars, made of strongly magnetized matter. The neutron stars are described by SLy equation of state, the strange quark stars by an equation of state based on the MIT Bag model. The stellar models are based on an a priori assumed density dependence of the magnetic field and thus anisotropy. Our study shows that not only the presence of a strong magnetic field and anisotropy, but also the orientation of the magnetic field itself, have an important influence on the physica…
In this paper, we present a new kind of stellar model using the Nariai IV metric. This model can be used to study the strange/quark stars(which is our present interest, though it can also be applicable to neutron stars). We present a mass-radius region where all the regularity conditions, energy conditions, the TOV equation, and stability conditions are satisfied. According to our model, strange stars having mass up to $1.9165M_{\odot}(=2.81 km)$ is stable. A strange star having a mass greater than $1.9165M_{\odot}$ violates the stability conditions. This model can be very useful to predict th…
Oscillation modes of isolated compact stars can, in principle, be a fingerprint of the equation of state (EoS) of dense matter. We study the non-radial high-frequency l=2 spheroidal modes of neutron stars and strange quark stars, adopting a two-component model (core and crust) for these two types of stars. Using perturbed fluid equations in the relativistic Cowling approximation, we explore the effect of a strangelet or hadronic crust on the oscillation modes of strange stars. The results differ from the case of neutron stars with a crust. In comparison to fluid-only configurations, we find th…
