The outflowing disks of B[e] supergiants and unclassified B[e] stars

Michaela Kraus; Marcelo Borges Fernandes

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The outflowing disks of B[e] supergiants and unclassified B[e] stars

Michaela Kraus·Marcelo Borges Fernandes

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Abstract

B[e] supergiants are known to possess outflowing cool disks but also some unclassified B[e] stars show clear indications for the presence of a neutral disk. We derive constraints on the disk mass loss rates, temperature distributions and disk opening angles for the Small Magellanic Cloud B[e] supergiant Hen S 18 and the unclassified galactic B[e] star Hen 2-90 by modeling the line luminosities of the [OI] lines arising in their optical spectrum. These lines are supposed to form in a hydrogen neutral disk. We find disk mass fluxes of order 3.4 10^-4 g s^-1 cm^-2 and 5.5 10^{-1} g s^{-1}cm^{-2} resulting in disk mass loss rates of 1.0 10^{-4} M_sun yr^{-1} and 1.5 10^{-5} M_sun yr^{-1} for Hen S 18 and Hen 2-90, respectively.

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Michaela Kraus, Marcelo Borges Fernandes. 2004-12-16. The outflowing disks of B[e] supergiants and unclassified B[e] stars. https://arxiv.org/abs/astro-ph/0408073

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