相关论文: Classifications of Twin Star Solutions for a Const…
We present a model of compact stars with a dark matter core. The hadronic equation of state is based on the parity doublet model and does not present a phase transition to quark matter. Instead, a strong first-order phase transition to dark…
We discuss the "constant speed of sound" (CSS) parametrization of the equation of state of high-density matter and its application to the field correlator method (FCM) model of quark matter. We show how observational constraints on the…
The twin star configuration, where two neutron stars share the same mass but exhibit different radii, arises from a strong first-order phase transition within the stellar interior. In widely used equation of state (EoS) meta-models, such as…
We study the mass-radius curve of hybrid stars, assuming a single first-order phase transition between nuclear and quark matter, with a sharp interface between the quark matter core and nuclear matter mantle. We use a generic…
In the present study, we employ three distinct, physically motivated speed of sound bounds to construct hybrid models, where the high-density phase is described by the maximally stiff equation of state. In particular, we consider the bounds…
We perform a model-agnostic Bayesian analysis of the neutron-star-matter equation of state (EoS), using known ab-initio constraints and astrophysical observations to limit its behavior at intermediate densities. Permitting explicit…
We introduce a parametrized density-dependent speed of sound and construct an ensemble of equations of state for neutron stars which are found to closely resemble the realistic equations of state calculated using relativistic mean field…
From the observation of both heavy neutron stars and light ones with small radii, one anticipates a steep rise in the speed of sound of nuclear matter as a function of baryon density up to values close to the causal limit. A question…
If a phase transition is allowed to take place in the core of a compact star, a new stable branch of equilibrium configurations can appear, providing solutions with the same mass as the purely hadronic branch and hence giving rise to…
The existence of massive compact stars $(M\gtrsim 2.1 M_{\odot})$ implies that the conformal limit of the speed of sound $c_s^2=1/3$ is violated if those stars have a crust of ordinary nuclear matter. Here we show that, if the most massive…
Astrophysical observations from NICER and gravitational wave data constrain the properties of matter at the cores of neutron stars, enabling us to probe high-density matter with greater accuracy. To understand its implications for neutron…
Determining the equation of state of matter at nuclear density and hence the structure of neutron stars has been a riddle for decades. We show how the imminent detection of gravitational waves from merging neutron star binaries can be used…
The upper bound of the speed of sound in dense nuclear matter is one of the most interesting but still unsolved problems in Nuclear Physics. Theoretical studies in connection with recent observational data of isolated neutron stars as well…
Twin stars are predicted to exist in nature if the hadron-to-quark phase transition is strong enough to form a new branch of hybrid stars, separated from the branch of neutron stars. We adopt an agnostic approach, using transition energy…
The equation of state is fundamental in describing matter under the extreme conditions characteristic of neutron stars and is central to advancing our understanding of dense matter physics. A critical challenge, however, lies in accurately…
The phase state of dense matter in the intermediate density range ($\sim$1-10 times the nuclear saturation density) is both intriguing and unclear and could have important observable effects in the present gravitational wave era of neutron…
We report on a three--month research project for undergraduate students about the mass-radius relation of compact stars. The equation of state used is constrained at low densities by well-established equations of state of the nuclear phase…
We present two types of models for hybrid compact stars composed of a quark core and a hadronic mantle with an abrupt first order phase transition at the interface which are in accordance with the latest astrophysical measurements of two 2…
Understanding the dense matter equation of state at extreme conditions is an important open problem. Astrophysical observations of neutron stars promise to solve this, with NICER poised to make precision measurements of mass and radius for…
We describe two fitting schemes that aim to represent the high-density part of realistic equations of state for numerical simulations such as neutron star oscillations. The low-density part of the equation of state is represented by an…