Related papers: Mass loss from inhomogeneous hot star winds II. Co…
Small-scale clumping in the winds of hot, massive stars is 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…
Small-scale inhomogeneities, or `clumping', in the winds of hot, massive stars are conventionally included in spectral analyses by assuming optically thin clumps. To reconcile investigations of different diagnostics using this microclumping…
We investigate the impact of optically thick clumping on stellar wind diagnostics in O supergiants and constrain wind parameters associated with porosity in velocity space. This is the first time the effects of optically thick clumping have…
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…
The true mass-loss rates from massive stars are important for many branches of astrophysics. For the correct modeling of the resonance lines, which are among the key diagnostics of stellar mass-loss, the stellar wind clumping turned out to…
Mass loss governs the evolution of massive stars and shapes the stellar surroundings. To quantify the impact of the stellar winds we need to know the exact mass-loss rates; however, empirical constraints on the rates are hampered by limited…
We review recent developments regarding radiation driven mass loss from OB-stars. We first summarize the fundamental theoretical predictions, and then compare these to observational results (including the VLT-FLAMES survey of massive…
Recent studies of O-type stars demonstrated that discrepant mass-loss rates are obtained when different diagnostic methods are employed - fitting the unsaturated UV resonance lines (e.g. P v) gives drastically lower values than obtained…
We constrain wind parameters of a sample of 18 O-type stars in the LMC, through analysis with stellar atmosphere and wind models including the effects of optically thick clumping. This allows us to determine the most accurate spectroscopic…
Winds of massive stars have density inhomogeneities (clumping) that may affect the formation of spectral lines in different ways, depending on their formation region. Most of previous and current spectroscopic analyses have been performed…
Mass loss is a key process in the evolution of massive stars, and must be understood quantitatively to be successfully included in broader astrophysical applications. In this review, we discuss various aspects of radiation driven mass loss,…
[Abridged] Clumping in the radiation-driven winds of hot, massive stars affects the derivation of synthetic observables across the electromagnetic spectrum. We implement a formalism for treating wind clumping - in particular the…
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…
Context. The uncertainty in the degree to which radiation-driven winds of hot stars might be affected by small inhomogeneities in the density leads to a corresponding uncertainty in the determination of the atmospheric mass loss rates from…
We study the effects of optically thick clumps, non-void inter-clump medium, variation of the onset of clumping, and velocity dispersion inside clumps on the formation of resonance lines. For this purpose we developed a full 3-D Monte Carlo…
Context. Mass-loss, occurring through radiation driven supersonic winds, is a key issue throughout the evolution of massive stars. Two outstanding problems are currently challenging the theory of radiation-driven winds: wind clumping and…
Recent results strongly challenge the canonical picture of massive star winds: various evidence indicates that currently accepted mass-loss rates, Mdot, may need to be revised downwards significantly. This is because the most commonly used…
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…
Hot, massive (OB) stars experience strong line-driven stellar winds and mass loss. As the majority of efficient driving lines are metallic, the amount of wind driving and mass loss is dependent on the stellar metallicity Z. In addition,…
The clumping of massive star winds is an established paradigm, which is confirmed by multiple lines of evidence and is supported by stellar wind theory. We use the results from time-dependent hydrodynamical models of the instability in the…