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تسجيل مستخدم جديدOn the Structure and Kinematics of Nebulae around LBVs and LBV Candidates in the LMC
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Kerstin Weis
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We present a detailed analysis of the morphology and kinematics of nebulae around LBVs and LBV candidates in the Large Magellanic Cloud. HST images and high-resolution Echelle Spectra were used to determine the size, shape, brightness, and expansion velocities of the LBV nebulae around R127, R143, and S61. For S Dor, R71, R99, and R84 we discuss the possible presence of nebular emission, and derive upper limits for the size and lower limits on the expansion velocities of possible nebulae. Including earlier results for the LBV candidates S119 and SK-69 279 we find that in general the nebulae around LBVs in the LMC are comparable in size to those found in the Milky Way. The expansion velocities of the LMC nebulae, however, are significantly lower--by about a factor of 3 to 4--than those of galactic nebulae of comparable size. Galactic and LMC nebulae show about the same diversity of morphologies, but only in the LMC do we find nebulae with outflow. Bipolarity--at least to some degree--is found in nebulae in the LMC as well as in the Milky Way, and manifests a much more general feature among LBV nebulae than previously known.
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