Comoving frame models of hot star winds
نویسندگان
چکیده
منابع مشابه
Spectral Modeling of X-rays from Hot Star Winds
We attempt to determine the mass-loss rates of several O stars using x-ray spectra from Chandra’s archive. Models of x-ray production in hot star winds predict broad, asymmetric emission lines, but observed lines tend to be much more symmetric. Such symmetry can be explained by either lowering the values of the mass-loss rate for these winds, or by reassessing the commonly accepted models of x-...
متن کاملModelling the clumping-induced polarimetric variability of hot star winds
Context. Clumping in the winds of massive stars may significantly reduce empirical mass-loss rates, and which in turn may have a large impact on our understanding of massive star evolution. Aims. Here, we investigate wind-clumping through the linear polarization induced by light scattering off the clumps. Methods. Through the use of an analytic wind clumping model, we predict the time evolution...
متن کاملFUSE Observations of Variability in Hot-Star Winds
New constraints on the large-scale wind structures responsible for discrete absorption components are obtained from far-ultraviolet time-series observations of O supergiants in the Large Magellanic Cloud. 1. What Causes DACs? Discrete absorption components (DACs) are optical depth enhancements in the absorption troughs of P Cygni profiles, which (a) occur very commonly in wind profiles of OB-ty...
متن کاملMass loss from inhomogeneous hot star winds I. Resonance line formation in 2D models
Context. The mass-loss rate is a key parameter of hot, massive stars. Small-scale inhomogeneities (clumping) in the winds of these stars are conventionally included in spectral analyses by assuming optically thin clumps, a void inter-clump medium, and a smooth velocity field. To reconcile investigations of different diagnostics (in particular, unsaturated UV resonance lines vs. Hα/radio emissio...
متن کاملGamma-ray bursts in the comoving frame
We estimate the bulk Lorentz factor 0 of 31 gamma-ray bursts (GRBs) using the measured peak time of their afterglow light curves. We consider two possible scenarios for the estimate of 0: the case of a homogeneous circumburst medium or a wind density profile. The values of 0 are broadly distributed between few tens and several hundreds with average values ∼138 and ∼66 for the homogeneous and wi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2017
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201730723