Related papers: Atmospheric Effects on Neutron Star Parameter Cons…
Exoplanet characterization is one of the main foci of current exoplanetary science. For super-Earths and sub-Neptunes, we mostly rely on mass and radius measurements, which allow to derive the body's mean density and give a rough estimate…
The study of neutron stars, or more general compact stars, is a topic of central interest in nuclear astrophysics. Furthermore, neutron stars serve as the only physical systems whose properties can be used to infer information on cold and…
In this paper, we discuss the impact of the following laboratory experiments and astrophysical observation of neutron stars (NSs) on its equation of state (EoS): (a) The new measurement of neutron skin thickness of $\rm ^{208} \! Pb$,…
The Neutron Star Interior Composition Explorer (NICER) recently measured the mass and equatorial radius of the isolated neutron star PSR J0030+0451. We use these measurements to infer the moment of inertia, the quadrupole moment, and the…
r-mode oscillations have been shown to have a significant potential to constrain the composition of fast spinning neutron stars. Due to their high rotation rates, millisecond pulsars (MSPs) provide a unique platform to constrain the…
Properties of X-ray radiation emitted from the polar caps of a radio pulsar depend not only on the cap temperature, size, and position, but also on the surface chemical composition, magnetic field, and neutron star's mass and radius.…
X-ray burst spectra have long been used to estimate neutron star masses and radii. These estimates assumed that burst spectra are accurately described by the model atmosphere spectra developed over the last three decades. We compared RXTE…
Analyses for the NICER data indicate that there is no significant variation of the compact star radii within the mass range of 1.4 to 2.0 solar masses. Yamamoto et al. [Phys. Rev. C 108, 035811 (2023)] concluded recently that ``this feature…
The boundary conditions of the heliosphere are set by the ionization, density and composition of inflowing interstellar matter. Constraining the properties of the Local Interstellar Cloud (LIC) at the heliosphere requires radiative transfer…
XMM-Newton observations of the middle-aged radio-quiet $\gamma$-ray pulsar J0554+3107 allowed us, for the first time, firmly identify it in X-rays by detection of pulsations with the pulsar period. In the 0.2-2 keV band, the pulse profile…
We present a new method of matching observations of Type I (thermonuclear) X-ray bursts with models, comparing the predictions of a semi-analytic ignition model with X-ray observations of the accretion-powered millisecond pulsar SAX…
We present a detailed investigation of atmospheres around accreting neutron stars with high magnetic field ($B\gtrsim 10^{12}$ G) and low luminosity ($L\lesssim 10^{33}$ erg/s). We compute the atmospheric structure, intensity and emergent…
We present results of recent Neutron Star Interior Composition Explorer observations of the accreting millisecond X-ray pulsar IGR J17062-6143 that show that it resides in a circular, ultracompact binary with a 38 minute orbital period.…
I summarize some constraints on the physics of neutron stars arising from X-ray observations of the surfaces of neutron stars, focusing on using models of low-magnetic-field neutron star atmospheres to interpret their X-ray spectra. I…
The fastest and heaviest pulsar, PSR J0952-0607, with a mass of $M=2.35\pm0.17 \ M_\odot$, has recently been discovered in the disk of the Milky Way Galaxy. In response to this discovery, a new RMF model, `NITR' has been developed. The NITR…
A major uncertainty in the structure and dynamics of magnetized, radiation pressure dominated neutron star accretion columns in X-ray pulsars and pulsating ultraluminous X-ray sources is that they are thought to be subject to the photon…
We analyze families of hybrid equations of state of cold QCD matter, which combine input from gauge/gravity duality and from various ab initio methods for nuclear matter at low density, and predict that all neutron stars are fully hadronic…
We report on a series of spectroscopic observations of PSR J1311-3430, an extreme black-widow gamma-ray pulsar with a helium-star companion. In a previous study we estimated the neutron star mass as M_NS= 2.68+/-0.14M_Sun (statistical…
We study the impact of modern stellar atmospheres that take into account the effects of stellar winds, departures from LTE and line blanketing ("CoStar" models) on the ionization structure of HII regions. Results from a large grid of…
Intense magnetic fields in the atmospheres of neutron stars render non-trivial angular dependence of intensity and polarization of soft X-ray emission originating from their surfaces. By tracking the complex electric field vector for each…