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arXiv · 1908.03311

The nascent wind of AGB star R Doradus: evidence for a recent episode of enhanced mass loss

P. T. Nhung·D. T. Hoai·P. Tuan-Anh·P. Darriulat·P. N. Diep·N. T. Phuong·T. T. Thai
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Abstract

We analyse ALMA observations of the SO($J_K=6_5-5_4$) emission of the circumstellar envelope of oxygen-rich AGB star R Dor, probing distances between 20 and 100 au from the star where the nascent wind is building up. We give evidence for the slow wind to host, in addition to a previously observed rotating disc, a radial outflow covering very large solid angles and displaying strong inhomogeneity both in direction and radially: the former takes the form of multiple cores and the latter displays a radial dependence suggesting an episode of enhanced mass loss having occurred a century or so ago.

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P. T. Nhung, D. T. Hoai, P. Tuan-Anh, P. Darriulat, P. N. Diep, N. T. Phuong, T. T. Thai. 2019-08-09. The nascent wind of AGB star R Doradus: evidence for a recent episode of enhanced mass loss. https://doi.org/10.1093/mnras/stz2675

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