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We investigate the possible role of line-driven winds in the circumstellar envelope in B[e] stars, mainly the role of the $Omega$-slow wind solution, which is characterized by a slower terminal velocity and higher mass-loss rate, in comparison with the standard (m-CAK) wind solution. In this work, we assume two scenarios: 1) a spherically symmetric star and 2) a scenario that considers the oblate shape, considering only the oblate correction factor. For certain values of the line force parameters (according to previous works), we obtain in both scenarios a density contrast $gtrsim10^{2}$ between equatorial and polar densities, characterized for a fast polar wind and a slow and denser wind when the $Omega$-slow wind solution is obtained. All this properties are enhanced when the oblate correction factor is included in our calculations.
B[e] supergiants are evolved massive stars with a complex circumstellar environment. A number of important emission features probe the structure and the kinematics of the circumstellar material. In our survey of Magellanic Cloud B[e] supergiants we f
MWC158 is a star with the B[e] phenomenon that shows strong spectrophotometric variability (in lines and in UV and visible continuum) attributed to phases of shell ejection. The evolutionary stage of this star was never clearly determined. Previous i
The effects of rapid rotation and bi--stability upon the density contrast between the equatorial and polar directions of a B[e] supergiant are investigated. Based on a new slow solution for different high rotational radiation--driven winds and the fa
The resolved stellar populations of local galaxies, from which it is possible to derive complete star formation and chemical enrichment histories, provide an important way to study galaxy formation and evolution that is complementary to lookback time
Thanks to the high spatial resolution provided by long baseline interferometry, it is possible to understand the complex circumstellar geometry around stars with the B[e] phenomenon. These stars are composed by objects in different evolutionary stage