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arXiv · astro-ph/0606457

Mira B Rejuvenated

Brian E. Wood·Margarita Karovska
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Abstract

Recent ultraviolet spectra from the Hubble Space Telescope (HST) and Far Ultraviolet Spectroscopic Explorer (FUSE) satellites demonstrate that UV line and continuum fluxes observed from Mira B are increasing back towards the levels that the International Ultraviolet Explorer observed in 1979-1980 and 1990-1995, after having been found in a very low state by HST and FUSE in 1999-2001. The UV emission is associated with accretion of material onto Mira B from Mira A's massive wind, so the variability is presumably due to variations in accretion rate. From wind absorption features, we estimate a Mira B mass loss rate of 2.5e-12 M_sun/yr, indicating that Mira B's wind has increased in strength along with the accretion rate. The UV variability may be associated with a previously reported 14-year periodicity in Mira B's optical emission.

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Brian E. Wood, Margarita Karovska. 2006-06-19. Mira B Rejuvenated. https://doi.org/10.1086/506383

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