相关论文: Extensive Observational Evidence for Massive Star …
The impact of FUSE upon the fundamental parameters of OB stars and Wolf-Rayet stars is reviewed. The stellar wind signatures available in the far-UV provide us with important additional diagnostics of effective temperature. Together with…
We investigate the line-profile variability (lpv) of H-alpha for a large sample of O-type supergiants. We used the Temporal Variance Spectrum (TVS) analysis, developed by Fullerton et al 1996 and modified by us to take into account the…
A small subset of Galactic O-stars possess surface magnetic fields that alter the outflowing stellar wind by magnetically confining it. Key to the magnetic confinement is that it induces rotational modulation of spectral lines over the full…
By extending our self-consistent MHD simulations for the solar wind, we study the evolution of stellar winds of solar-type stars from early main sequence stage to red giant phase. Young solar-type stars are active and the mass loss rates…
Aims: We study the acceleration of the stellar winds of rapidly rotating low mass stars and the transition between the slow magnetic rotator and fast magnetic rotator regimes. We aim to understand the properties of stellar winds in the fast…
The most massive stars dominate the chemical enrichment, mechanical and radiative feedback, and energy budget of their host environments. Yet how massive stars initially form and how they evolve throughout their lives is ambiguous. The mass…
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…
Aims: We develop a method for estimating the properties of stellar winds for low-mass main-sequence stars between masses of 0.4 and 1.1 solar masses at a range of distances from the star. Methods: We use 1D thermal pressure driven…
We use Geneva-evolution-code to run evolutionary tracks for stellar masses ranging from $20$ to $85$ $M_\odot$ at SMC metallicity ($Z=0.002$). We upgrade the recipe for stellar winds by adopting our self-consistent m-CAK prescription, which…
The existence of a mass-metallicity (MZ) relation in star forming galaxies at all redshift has been recently established. We aim at studying some possible physical mechanisms contributing to the MZ relation by adopting analytical solutions…
Understanding the complex behavior of High Mass X-ray binaries (HMXBs) is not possible without detailed information about their donor stars. While crucial, this turns out to be a challenge on multiple fronts. First, multi-wavelength…
The mass loss from Wolf-Rayet (WR) stars is of fundamental importance for the final fate of massive stars and their chemical yields. Its Z-dependence is discussed in relation to the formation of long-duration Gamma Ray Bursts (GRBs) and the…
(shortened) The first couple of stellar generations may have been massive, of order 100 Msun, and to have played a dominant role in galaxy formation and the chemical enrichment of the early Universe. Some fraction of these objects may have…
The winds of massive stars are important for their direct impact on the interstellar medium, and for their influence on the final state of a star prior to it exploding as a supernova. However, the dynamics of these winds is understood…
We study the spectroscopic appearance of very massive stars and their effect on the integrated light of starbursts at low metallicity (Z). We adopt two frameworks for the mass loss rates of VMS: in one case we assume no Z dependence, in the…
We use ultraviolet space-based (FUSE, HST) and optical/IR ground-based (2.3m MSSSO, NTT) spectroscopy to determine the physical parameters of six WC4-type Wolf-Rayet stars in the Large Magellanic Cloud. Stellar parameters are revised…
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.…
A review of observational evidence in favour of a metallicity dependence of WN and WC stars is presented. New near-IR studies of Milky Way, LMC and SMC early-type WN stars are presented, with weake winds amongst WN stars containing…
Determining how much mass is removed by stellar winds is crucial to understanding massive star evolution and feedback. However, traditional spectroscopic diagnostics in the UV and optical are not sensitive enough to characterize weak…
Massive stars with their strong ionizing radiation and strong stellar winds are the key feedback agents of the universe. Stellar winds of massive stars are often measured by fitting resonance lines in the UV using non-LTE stellar atmosphere…