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The activity of massive stars approaching core-collapse can strongly affect the appearance of the star and its subsequent supernova. Late-phase convective nuclear burning generates waves that propagate toward the stellar surface, heating the envelope and potentially triggering mass loss. In this work, we improve on previous one-dimensional models by performing two-dimensional simulations of the pre-supernova mass ejection phase due wave heat deposition. Beginning with stellar evolutionary models of a 15 $M_{odot}$ red supergiant star during core O-burning, we treat the energy deposition rate and duration as model parameters and examine the mass-loss dependence and the pre-explosion morphology accordingly. Unlike one-dimensional models, density
The post main-sequence evolution of massive stars is very sensitive to many parameters of the stellar models. Key parameters are the mixing processes, the metallicity, the mass-loss rate and the effect of a close companion. We study how the red super
We report mid- to far-infrared imaging and photomety from 7 to 37 microns with SOFIA/FORCAST and 2 micron adaptive optics imaging with LBTI/LMIRCam of a large sample of red supergiants (RSGs) in four Galactic clusters; RSGC1, RSGC2=Stephenson 2, RSGC
Mass loss is an important activity for red supergiants (RSGs) which can influence their evolution and final fate. Previous estimations of mass loss rates (MLRs) of RSGs exhibit significant dispersion due to the difference in method and the incomplete
We aim to investigate mass loss and luminosity in a large sample of evolved stars in several Local Group galaxies with a variety of metalliticies and star-formation histories: the Small and Large Magellanic Cloud, and the Fornax, Carina, and Sculptor
SN2005ip was a TypeIIn event notable for its sustained strong interaction with circumstellar material (CSM), coronal emission lines, and IR excess, interpreted as shock interaction with the very dense and clumpy wind of an extreme red supergiant. We