相关论文: Monte Carlo Simulations of Polarimetric and Light …
Massive star winds are complex radiation-hydrodynamic (sometimes magnetohydrodynamic) outflows that are propelled by their enormously strong luminosities. The winds are often found to be structured and variable, but can also display…
Massive star winds are structured both stochastically ("clumps") and often coherently (Co-rotation Interaction Regions, or CIRs). Evidence for CIRs threading the winds of Wolf-Rayet (WR) stars arises from multiple diagnostics including…
The intriguing WN4b star WR6 has been known to display epoch-dependent spectroscopic, photometric and polarimetric variability for several decades. In this paper, we set out to verify if a simplified analytical model in which Corotating…
We present two-dimensional hydrodynamical simulations of corotating stream structure in the wind from a rotating O star, together with resulting synthetic line profiles showing discrete absorption components (DACs). An azimuthal variation…
A Monte Carlo method is used to calculate the profiles and the polarization of the Raman scattered O VI lines(lambda lambda 6827,7088) in symbiotic stars. A point-like isotropic UV radiation source is assumed and a simple spherical wind…
Almost all early-type stars show Discrete Absorption Components (DACs) in their ultraviolet spectral lines. These can be attributed to Co-rotating Interaction Regions (CIRs): large-scale spiral-shaped structures that sweep through the…
Polarization is an important tool to further the understanding of interstellar dust and the sources behind it. In this paper we describe our implementation of polarization that is due to scattering of light by spherical grains and electrons…
Massive star binaries are critical laboratories for measuring masses and stellar wind mass-loss rates. A major challenge is inferring viewing inclination and extracting information about the colliding wind interaction (CWI) region.…
OB stars are known to exhibit various types of wind variability, as detected in their ultraviolet spectra, amongst which are the ubiquitous discrete absorption components (DACs). These features have been associated with large-scale…
Corotating Interaction Regions (CIRs) are recurring structures in the solar wind, characterized by interactions between fast and slow solar wind streams that compress and heat plasma. This study investigates the polytropic behavior of…
We have modelled the circumstellar envelope of {\it o} Ceti (Mira) using new observational constraints. These are obtained from photospheric light scattered in near-IR vibrational-rotational lines of circumstellar CO molecules at 4.6…
Fast-rotating Wolf-Rayet (WR) stars are potential progenitors of long gamma-ray bursts, but observational verification is challenging. Spectral lines from their expanding stellar wind obscure accurate rotational velocity measurements.…
The structured winds of single massive stars can be classified into two broad groups: stochastic structure and organized structure. While the former is typically identified with clumping, the latter is typically associated with rotational…
Soft X-ray emission from neutron stars affords powerful diagnostic tools for uncovering their surface and interior properties, as well as their geometric configurations. In the atmospheres of neutron stars, the presence of magnetic fields…
Light transfer in gradient-index media generally follows curved ray trajectories, which will cause light beam to converge or diverge during transfer and induce the rotation of polarization ellipse even when the medium is transparent.…
Bow shocks and related density enhancements produced by the winds of massive stars moving through the interstellar medium provide important information regarding the motions of the stars, the properties of their stellar winds, and the…
We present the first numerical radiative transfer simulation of multiple light scattering in dust configurations containing aligned non-spherical (spheroidal) dust grains. Such models are especially important if one wants to explain the…
In this work, we investigate if gravitational microlensing can magnify the polarization signal of a stellar spot and make it be observable. A stellar spot on a source star of microlensing makes polarization signal through two channels of…
The intense magnetic fields of neutron stars naturally lead to strong anisotropy and polarization of radiation emanating from their surfaces, both being sensitive to the hot spot position on the surface. Accordingly, pulse phase-resolved…
We study the polarization produced by scattering from dust in a bow shock-shaped region of enhanced density surrounding a stellar source, using the Monte Carlo radiative transfer code SLIP. Bow shocks are structures formed by the…