相关论文: Modeling X-ray Bursting Neutron Star Atmospheres
Compton scattering is the nonresonant inelastic scattering of an x-ray photon by an electron and has been used to probe the electron momentum distribution in gas-phase and condensed-matter samples. In the low x-ray intensity regime, Compton…
Numerical simulations of radiative processes in magnetized compact sources such as hot accretion disks around black holes, relativistic jets in active galaxies and gamma-ray bursts are complicated because the particle and photon…
Spectral properties of super-Eddington accretion flows are investigated by means of a parallel line-of-sight calculation. The subjacent model, taken from two-dimensional radiation hydrodynamic simulations by Ohsuga et al. (2005), consists…
Recent observations by XMM-Newton detected rotational pulsations in the total brightness and spectrum of several neutron stars. To properly interpret the data, accurate modeling of neutron star emission is necessary. Detailed analysis of…
We present a sequence of toy models for irradiated planet atmospheres, in which the effects of geometry and energy redistribution are modelled self-consistently. We use separate but coupled grey atmosphere models to treat the ingoing…
We present model atmospheres and theoretical spectra for X-ray bursters. Our models include the effects of Compton scattering on free electrons. The atmospheres have compositions that are mixtures of hydrogen, helium, and iron. For our…
We use two-dimensional, general relativistic, viscous, radiation hydrodynamic simulations to study the impact of a Type I X-ray burst on a hot and geometrically thick accretion disk surrounding an unmagnetized, non-rotating neutron star.…
Neutron stars accreting matter from low-mass binary companions are observed to undergo bursts of X-rays due to the thermonuclear explosion of material on the neutron star surface. We use recent results on superfluid and superconducting…
Winds are an important ingredient in the evolution of X-ray binary (XRB) systems, particularly those at high accretion rates such as ultra-luminous X-ray sources (ULXs), because they may regulate the accretion of matter onto the compact…
Nuclear burning and its dependence on the mass accretion rate are fundamental ingredients for describing the complicated observational phenomenology of neutron stars in binary systems. Motivated by high quality burst rate data emerging from…
X-ray pulsars experiencing extreme mass accretion rates can produce neutrino emission in the MeV energy band. Neutrinos in these systems are emitted in close proximity to the stellar surface and subsequently undergo gravitational bending in…
A phase-resolved analysis on the X-ray spectrum of Ultra-Luminous X-ray Pulsar (ULXP) NGC 300 ULX-1 is performed with data taken with XMM-Newton and NuSTAR on 2016 December 16th. In addition to the classical phase-restricting analysis, a…
Type-I X-ray bursts arise from unstable thermonuclear burning of accreted fuel on the surface of neutron stars. In this chapter we review the fundamental physics of the burning processes, and summarise the observational, numerical, and…
We present a method for computing the net transmission of X-rays emitted by shock-heated plasma distributed throughout a partially optically thick stellar wind from a massive star. We find the transmission by an exact integration of the…
The Cosmic Neutrino Background (C$\nu$B) constitutes the last observable prediction of the standard cosmological model, which has yet to be detected directly. In this work, we show how the coherent scattering of neutrinos off dense neutron…
The atmospheres of planets (including Earth) and the outer layers of stars have often been treated in radiative transfer as plane-parallel media, instead of spherical shells, which can lead to inaccuracy, e.g. limb darkening. We give an…
The nature of ultraluminous X-ray sources in nearby galaxies is one of the major open questions in modern X-ray astrophysics. One possible explanation for these objects is an inhomogeneous, radiation dominated accretion disk around a $\sim…
We describe X-ray production in the atmospheres of hot, early-type stars in the framework of a ``stochastic shock model''. The extended envelope of a star is assumed to possess numerous X-ray emitting ``hot'' zones that are produced by…
The beaming pattern of radiation emitted by a relativistically moving source like jets in microquasars, AGN and GRBs, is a key issue for understanding of acceleration and radiation processes in these objects. In this paper we introduce a…
We present a detailed investigation of atmospheres around accreting neutron stars with high magnetic field ($B\gtrsim 10^{12}$ G) and low luminosity ($L\lesssim 10^{33}$ erg/s). We compute the atmospheric structure, intensity and emergent…