Related papers: Pulsations as a mass-loss trigger in evolved hot s…
We discuss the physics and the evolution of a typical massive star passing through an evolutionary stage similar to that of Betelgeuse. After a brief introduction recalling various observed parameters of Betelgeuse, we discuss the…
Luminous blue variables (LBVs) are characterized by semi-periodic episodes of enhanced mass-loss, or outburst. The cause of these outbursts has thus far been a mystery. One explanation is that they are initiated by kappa-effect pulsations…
We investigate the evolution of collisionally merged stars with mass of ~100 MSun which might be formed in dense star clusters. We assumed that massive stars with several tens Msun collide typically after ~1Myr of the formation of the…
The most massive stars are thought to lose a significant fraction of their mass in a steady wind during the main-sequence and blue supergiant phases. This in turn sets the stage for their further evolution and eventual supernova, with…
Evolved massive stars are known to undergo outflow with high mass ejections, resulting in the loss of a substantial portion of their envelopes. One proposed mechanism driving these events is the release or deposition of energy within the…
Eclipses and pulsations are the two primary ways in which the physical properties of stars can be deduced and used to improve our understanding of stellar theory. An obvious idea is to combine these two analyses into the study of pulsating…
The fact that the majority of the youngest radio pulsars are surrounded by expanding supernova remnants is strong evidence that neutron stars are produced in the supernovae of massive stars. In many cases, the pulsar appears significantly…
We discuss the various post-main sequence phases of massive stars, focusing on Wolf-Rayet stars, Luminous Blue Variables, plus connections with other early-type and late-type supergiants. End states for massive stars are also investigated,…
The development and progress of the studies of winds and mass loss from hot stars, from about 1965 up to now, is discussed in a personal historical perspective. The present state of knowledge about stellar winds, based on papers presented…
How massive stars die -- what sort of explosion and remnant each produces -- depends chiefly on the masses of their helium cores and hydrogen envelopes at death. For single stars, stellar winds are the only means of mass loss, and these are…
We discuss the spin evolution of pulsars in the case where a superfluid component of the star is coupled to the observable crust on long, spindown timescales. The momentum transfer from the superfluid interior results in an apparent decay…
Mass loss from massive stars ($\ga 8 \msun$) can result in the formation of circumstellar wind blown cavities surrounding the star, bordered by a thin, dense, cold shell. When the star explodes as a core-collapse supernova (SN), the…
We present results of pulsation analyses of B-type supergiant models with masses of $14 - 18 M_\odot$, considering evolutionary stages before and after helium core ignition. Using a non-adiabatic pulsation code, we compute instability…
We study the runaway mass loss process of major eruptions of luminous blue variables (LBVs) stars, such as the 1837-1856 Great Eruption of Eta Carinae. We follow the evolution of a massive star with a spherical stellar evolution numerical…
Massive stars less massive than ~30 Msol evolve into a red supergiant after the main sequence. Given a standard IMF, this means about 80% of all single massive stars will experience this phase. RSGs are dominated by convection, with a…
We investigate the dependence of pulse amplitudes of accreting millisecond pulsars on the masses of the neutron stars. Because the pulsation amplitudes are suppressed as the neutron stars become more massive, the probability of detection of…
Mass loss is a crucial component in stellar evolution models, since it largely determines the rate of evolution at the later stages of a star's life. The dust-driven outflows from AGB stars are particularly important in this regard.…
Massive stars becoming red supergiants lose a significant amount of their mass during that brief evolutionary phase. They then either explode as a hydrogen-rich supernova (SN Type II), or continue to evolve as a hotter supergiant (before…
Discoveries of planet- and stellar remnant-hosting pulsars challenge our understanding as the violent supernova explosion that forms the pulsar presumably destabilizes the system. Type II supernova explosions lead to the formation of…
Diffusion in cool B stars of the main sequence has been shown to strongly affect opacities and convection in cool B stars of the main sequence. We show here that diffusion in B stars maintains or enhances the excitation of pulsations in…