A high-speed bipolar outflow from the archetypical pulsating star mira a
Meaburn, J. ; López, J. A. ; Boumis, P. ; Lloyd, M. ; Redman, M. P.
Meaburn, J.
López, J. A.
Boumis, P.
Lloyd, M.
Redman, M. P.
Publication Date
2009-04-29
Type
Article
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Meaburn, J. López, J. A.; Boumis, P.; Lloyd, M.; Redman, M. P. (2009). A high-speed bipolar outflow from the archetypical pulsating star mira a. Astronomy & Astrophysics 500 (2), 827-831
Abstract
Optical images and high-dispersion spectra have been obtained of the ejected material surrounding the pulsating AGB star Mira A. The two streams of knots on either side of the star, found in far-ultraviolet (FUV) GALEX images, have now been imaged clearly in the light of Ha. Spatially resolved profiles of the same line reveal that the bulk of these knots form a bipolar outflow with radial velocity extremes of +/- 150 km s(-1) with respect to the central star. The south stream is approaching and the north stream receding from the observer. A displacement away from Mira A between the position of one of the south-stream knots in the new Ha image and its position in the previous Palomar Observatory Sky Survey (POSS I) red plate was noted. If interpreted as a consequence of expansion proper motions, the bipolar outflow is tilted at 69 degrees +/- 15 degrees to the plane of the sky, has an outflow velocity of 160 +/- 10 km s(-1) and is approximate to 1000 y old.
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Publisher
EDP Sciences
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Attribution-NonCommercial-NoDerivs 3.0 Ireland