The Case for Asymmetric Dust Around a C-Rich AGB star
Abstract
JHKL observations of the mass-losing carbon Mira variable IRAS 15194-5115 (II Lup) extending over about 18 years are presented and discussed. The pulsation period is 575 days and has remained essentially constant over this time span. The star has undergone an extensive obscuration minimum during this time. This is complex and, like such minima in similar objects, e.g. R For, does not fit the model predictions of a simple long term periodicity. Together with the high resolution observations of Lopez et al. the results suggest that the obscuration changes are due to the formation of dust clouds of limited extent in the line-of-sight. This is an RCB-type model. The effective reddening law at J and H is similar to that found for R For.
Cite
@article{arxiv.astro-ph/0308417,
title = {The Case for Asymmetric Dust Around a C-Rich AGB star},
author = {Michael W Feast and Patricia A Whitelock and Freddy Marang},
journal= {arXiv preprint arXiv:astro-ph/0308417},
year = {2009}
}
Comments
8 pages, 2 figures, accepted for publication in MNRAS