相关论文: Predictions of variable mass loss for Luminous Blu…

(Abridged) The behaviour of mass loss across bi-stability jump is a key uncertainty in models of massive stars. While an increase in mass loss is theoretically predicted, this has so far not been observationally confirmed. However,…

A debate has arisen regarding the importance of stationary versus eruptive mass loss for massive star evolution. The reason is that stellar winds have been found to be clumped, which results in the reduction of unclumped empirical mass-loss…

We present results of a long-term spectroscopic monitoring program (since mid 2009) of Luminous Blue Variables with the new HERMES echelle spectrograph on the 1.2 m Mercator telescope at La Palma (Spain). We investigate high-resolution…

Dust formation in the winds of hot stars is inextricably linked to the classic eruptive state of luminous blue variables (LBVs) because it requires very high mass loss rates, Mdot>10^(-2.5) Msun/year, for grains to grow and for the non-dust…

We present the results of Monte Carlo mass-loss predictions for hot low-mass stars, specifically for Subdwarf B (SdB) stars. It is shown that the mass-loss rates on the Horizontal Branch (HB) computed from radiative line-driven wind models…

The atmospheres and winds of C-type AGB stars are modeled with the 1D spherically symmetric radiation-hydrodynamical code DARWIN. To explore the metallicity-dependence of mass loss we calculate model grids at three different chemical…

In this paper we present new models of massive stars based on recent advancements in the theory of diffusive mixing and a new empirical formulation of the mass-loss rates of red supergiant stars. We compute two sets of stellar models of…

Second only to initial mass, the rate of wind-driven mass loss determines the final mass of a massive star and the nature of its remnant. Motivated by the need to reconcile observational values and theory, we use a recently vetted technique…

[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 present a spectroscopic analysis of VLT/X-Shooter observations of six O-type stars in the low-metallicity (Z ~ 1/7 Z\odot) galaxies IC 1613, WLM and NGC 3109. The stellar and wind parameters of these sources allow us, for the first time,…

Some studies have claimed the existence of a stellar upper-mass limit of 150 Msun. A factor that is often overlooked concerns the issue that there might be a significant difference between the present-day and the initial mass of the most…

The effects of gravitational settling and radiative levitation in the stellar atmospheres and envelopes of subdwarf B (sdB) stars strongly depend on the presence of weak winds. In the paper the existence of weak radiatively driven winds is…

Very massive stars (VMS) play a fundamental role in astrophysics due to their winds and supernovae (SN), and their role as massive black hole (BH) progenitors. However, their origin and evolution remain a significant challenge. Recent…

Massive O-type stars lose a significant fraction of their mass through radiation-driven winds, a process that critically shapes their evolution and feedback into the interstellar medium. Accurate predictions of mass-loss rates are essential…

An increasing number of non-terminal eruptions are being found in the numerous surveys for optical transients. Very little is known about these giant eruptions, their progenitors and their evolutionary state. A greatly improved census of…

The effect of photon frequency redistribution by line branching on mass-loss rates for hot luminous stars is investigated. Monte Carlo simulations are carried out for a range of OB-star models which show that previous mass-loss calculations…

The luminous blue variable (LBV) stars are peculiar very massive stars. The study of these stellar objects and their surroundings is important for understanding the evolution of massive stars and its effects on the interstellar medium. We…

It is well established that mass loss from AGB stars due to dust driven winds cannot be arbitrarily low. We model the mass loss from carbon rich AGB stars using detailed frequency-dependent radiation hydrodynamics including dust formation.…

Luminous blue variables are an intermediate stage in the evolution of high-mass stars characterized by extreme mass loss and substantial variability. The stars show large irregular episodic variations on timescales of years to decades in…

(Abridged) Stars more massive than $20-30M_{\odot}$ are so luminous that the radiation force on the cooler, more opaque outer layers can balance or exceed the force of gravity. These near or super-Eddington outer envelopes represent a long…