منابع مشابه
RED SUPERGIANTS AS POTENTIAL TYPE IIn SUPERNOVA PROGENITORS: SPATIALLY RESOLVED 4.6 μm CO EMISSION AROUND VY CMa AND BETELGEUSE
We present high-resolution 4.6 μm CO spectra of the circumstellar environments of two red supergiants (RSGs) that are potential supernova (SN) progenitors: Betelgeuse and VY Canis Majoris. Around Betelgeuse, CO emission within ±3 (±12 km s) follows a mildly clumpy but otherwise spherical shell, smaller than its ∼55 shell in K i λ7699. In stark contrast, 4.6 μm CO emission around VY CMa is coinc...
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We investigate the pulsational properties of RSG models – which we evolve from ZAMS masses in the range 10 to 20M – by means of linear and non-linear calculations. We find period and growth rate of the dominant fundamental mode to increase with increasing luminosity-to-mass ratio L/M . Our models obtain relatively large L/M values due to the inclusion of rotation in the evolutionary calculation...
متن کاملPost-red Supergiants
The yellow hypergiants are found in a stage between the massive Red Supergiants and the Wolf-Rayet stars. This review addresses current issues concerning the evolution of massive stars, concentrating on the transitional postRed Supergiant phase. Few yellow hypergiants are known and even fewer show direct evidence for having evolved off the Red Supergiant branch. Indeed, only two such rare objec...
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Observational evidence for anisotropy in supernovae (SN) and their phenomenological connection to jetted sources such as gamma-ray bursts have revived considerations of the role magnetohydrodynamic outflows might play therein. Understanding the types of dynamos that might operate in supernova progenitors is therefore relevant. In contrast to previous work, here we study an “interface dynamo” fo...
متن کاملThe Physical Properties of Red Supergiants
Red supergiants (RSGs) are a He-burning phase in the evolution of moderately massive stars (10-25M⊙). For many years, the assumed physical properties of these stars placed them at odds with the predictions of evolutionary theory. We have recently determined new effective temperatures and luminosities for the RSG populations of galaxies with a factor of ∼8 range in metallicity, including the Mil...
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ژورنال
عنوان ژورنال: Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
سال: 2017
ISSN: 1364-503X,1471-2962
DOI: 10.1098/rsta.2016.0270