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arXiv · 1011.3730

The nebulae around LBVs: a multiwavelength approach

Grazia Umana·Carla S. Buemi·Corrado Trigilio·Paolo Leto·Joseph L. Hora·Giovanni Fazio
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Abstract

We present first results of our study of a sample of Galactic LBV, aimed to contribute to a better understanding of the LBV phenomenon, by recovering the mass-loss history of the central object from the analysis of its associated nebula. Mass-loss properties have been derived by a synergistic use of different techniques, at different wavelengths, to obtain high-resolution, multi-wavelength maps, tracing the different emitting components coexisting in the stellar ejecta: the ionized/neutral gas and the dust. Evidence for asymmetric mass-loss and observational evidence of possible mutual interaction between gas and dust components have been observed by the comparison of mid-IR (Spitzer/IRAC, VLT/VISIR) and radio (VLA) images of the nebulae, while important information on the gas and dust composition have been derived from Spitzer/IRS spectra.

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Grazia Umana, Carla S. Buemi, Corrado Trigilio, Paolo Leto, Joseph L. Hora, Giovanni Fazio. 2010-11-16. The nebulae around LBVs: a multiwavelength approach. https://arxiv.org/abs/1011.3730

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