Related papers: Advances in mass-loss predictions
Most stars will experience episodes of substantial mass loss at some point in their lives. For very massive stars, mass loss dominates their evolution, although the mass loss rates are not known exactly, particularly once the star has left…
We study the influence of clumping on the predicted wind structure of O-type stars. For this purpose we artificially include clumping into our stationary wind models. When the clumps are assumed to be optically thin, the radiative line…
We present mass-loss predictions from Monte Carlo radiative transfer models for helium (He) stars as a function of stellar mass, down to 2 Msun. Our study includes both massive Wolf-Rayet (WR) stars and low-mass He stars that have lost…
Reliable predictions of mass-loss rates are important for massive-star evolution computations. We aim to provide predictions for mass-loss rates and wind-momentum rates of O-type stars, carefully studying the behaviour of these winds as…
One of the key questions in Astrophysics concerns the issue of whether there exists an upper-mass limit to stars, and if so, what physical mechanism sets this limit, which might also determine if the upper-mass limit is metallicity (Z)…
Understanding the evolution of massive binary stars requires accurate estimates of their masses. This understanding is critically important because massive star evolution can potentially lead to gravitational wave sources such as binary…
Clumping in hot star winds can significantly affect estimates of mass-loss rates, the inferred evolution of the star and the environmental impact of the wind. A hydrodynamical simulation of a colliding winds binary (CWB) with clumpy winds…
We compare the hot star wind models calculated assuming older solar abundance determination with models calculated using the recently published values derived from 3D hydrodynamical model atmospheres. We show that the use of new abundances…
Over the last years a new generation of model atmosphere codes, which include the effects of metal line-blanketing of millions of spectral lines in NLTE, has been used to re-determine the properties of massive stars through quantitative…
The fate of massive stars up to 300 Msun is highly uncertain. Do these objects produce pair-instability explosions, or normal Type Ic supernovae? In order to address these questions, we need to know their mass-loss rates during their lives.…
I provide an overview of the empirical mass-loss rates of hot and cool luminous stars. Stellar species included in this talk are luminous OB stars, Wolf-Rayet stars, asymptotic giant branch stars, and red supergiants. I discuss the scaling…
The polarimetric and photometric variability of Wolf-Rayet (WR) stars as caused by clumps in the winds, is revisited. In the model which is improved from Li et al. 2000, the radial expansion of the thickness is accounted for, but we retain…
It is observationally as well as theoretically well established that the winds of hot, massive OB-stars are highly structured on a broad range of spatial scales. This paper first discusses consequences of the small-scale structures…
Mass fluxes J are computed for the extragalactic O stars investigated by Tramper et al. (2011; TSKK). For one early-type O star, computed and observed rates agree within errors. However, for two late-type O stars, theoretical mass-loss…
Mass loss rates for the tenuous, hot winds of cool stars are extremely difficult to measure, yet they are a crucial ingredient in the stars' rotational evolution. We present a new method for measuring these mass loss rates in young,…
I start with a discussion of spherical winds and small-scale clumping, before continuing with various theories that have been proposed to predict how mass loss depends on stellar rotation -- both in terms of wind strength, as well as the…
Various theories have been proposed to predict how mass loss depends on the stellar rotation rate, both in terms of its strength, as well as its latitudinal dependence, crucial for our understanding of angular momentum evolution. Here we…
We present radiation-driven wind models for Luminous Blue Variables (LBVs) and predict their mass-loss rates. We study the effects of lower masses and modified abundances in comparison to the normal OB supergiants, and we find that the main…
The basic mechanisms responsible for producing winds from cool, late-type stars are still largely unknown. We take inspiration from recent progress in understanding solar wind acceleration to develop a physically motivated model of the…
Context: The mass-loss rate is a key parameter of massive stars. Adequate stellar atmosphere models are required for spectral analyses and mass-loss determinations. Present models can only account for the inhomogeneity of stellar winds in…