相关论文: O-star mass-loss rates at low metallicity

In an attempt to understand the extraordinarily small mass-loss rates of late-type O dwarfs, mass fluxes in the relevant part of (T_{eff}, g)-space are derived from first principles using a previously-described code for constructing moving…

Mass loss forms an important aspect of the evolution of massive stars, as well as for the enrichment of the surrounding ISM. Our goal is to predict accurate mass-loss rates and terminal wind velocities. These quantities can be compared to…

We have determined accurate values of the product of the mass-loss rate and the ion fraction of P^{4+}, Mdot q(P^{4+}), for a sample of 40 Galactic O-type stars by fitting stellar-wind profiles to observations of the P V resonance doublet…

[Abridged] We present a comprehensive study of the metallicity dependence of the mass-loss rates in stationary stellar winds of hot massive stars. Assuming a power-law dependence of mass loss on metallicity, Mdot \propto Z^{m}, and adopting…

We review the various techniques through which wind properties of massive stars - O stars, AB supergiants, Luminous Blue Variables (LBVs), Wolf-Rayet (WR) stars and cool supergiants - are derived. The wind momentum-luminosity relation (e.g.…

I discuss observational evidence -- independent of the direct spectral diagnostics of stellar winds themselves -- suggesting that mass-loss rates for O stars need to be revised downward by roughly a factor of three or more, in line with…

We study the stellar and wind properties of a sample of Galactic O dwarfs to track the conditions under which weak winds (i.e mass loss rates lower than ~ 1e-8 Msol/yr) appear. The sample is composed of low and high luminosity dwarfs…

We have calculated mass-loss rates for a grid of wind models covering a wide range of stellar parameters and have derived a mass-loss recipe for two ranges of effective temperature at either side of the bi-stability jump around spectral…

The rate at which massive stars eject mass in stellar winds significantly influences their evolutionary path. Cosmic rates of nucleosynthesis, explosive stellar phenomena, and compact object genesis depend on this poorly known facet of…

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…

We use a combination of VJHK and Spitzer} [3.6], [5.8] and [8.0] photometry, to determine IR excesses in a sample of LMC and SMC O stars. This sample is ideal for determining excesses because: 1) the distances to the stars, and hence their…

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…

[Abridged] Context: Radiation-driven mass loss plays a key role in the life-cycles of massive stars. However, basic predictions of such mass loss still suffer from significant quantitative uncertainties. Aims: We develop new…

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…

Massive stars lose a large fraction of their mass to radiation-driven winds throughout their entire life. These outflows impact both the life and death of these stars and their surroundings. Theoretical mass-loss rates of hot, massive stars…

Building upon a previous analysis of P V wind lines in LMC O stars, we analyze the P V wind lines in a sample of Galactic O stars which have empirical mass loss rates determined from either their radio fluxes or H alpha profiles. Since the…

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…

We use a combination of BVJHK and Spitzer [3.6], [5.8] and [8.0] photometry to determine IR excesses for a sample of 58 LMC and 46 SMC O stars. This sample is ideal for determining IR excesses because the very small line of sight reddening…

Stellar evolution models of massive stars are very sensitive to the adopted mass-loss scheme. The magnitude and evolution of mass-loss rates significantly affect the main sequence evolution, and the properties of post-main sequence objects,…

The winds of stars with very specific temperatures and luminosities are ideal for determining the magnitude and nature of mass loss in OB stars. I identify these stars and analyze their wind lines. The results are discussed within the…