Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-24T12:40:42.607Z Has data issue: false hasContentIssue false
  • English
  • Français

Dust-driven Winds Beyond Spherical Symmetry

Published online by Cambridge University Press:  01 April 2008

Peter Woitke
Peter Woitke*
Affiliation:
UK Astronomy Technology Centre, Blackford Hill, EH9 3HJ Edinburgh, Scotland, UK School of Physics & Astronomy, University of St Andrews, North Haugh, KY16 9SS St. Andrews, Scotland, UK, email: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

New 2D dynamical models for the winds of AGB stars are presented which include hydrodynamics with radiation pressure on dust, equilibrium chemistry, time-dependent dust formation theory, and coupled frequency-dependent Monte Carlo radiative transfer. The simulations reveal a much more complicated picture of the dust formation and wind acceleration as compared to 1D spherical wind models. Triggered by non-spherical pulsations or large-scale convective motions, dust forms event-like in the cooler regions above the stellar surface which are temporarily less illuminated, followed by the radial ejection of dust arcs and clumps. These simulations can possibly explain recent high angular resolution interferometric IR observations of red giants, which show an often non-symmetric and highly time-variable innermost dust formation and wind acceleration zone. The dependence of the mass-loss rates on stellar parameters is less threshold-like as used from 1D models, and therefore, it seems quite possible that the phenomenon of dust-driven winds may occur also in less evolved red giants.

Keywords

hydrodynamicsradiative transferstars: late-typestars: windsstars: mass loss
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 4 , Symposium S252: The Art of Modeling Stars in the 21st Century , April 2008 , pp. 229 - 234
Copyright
Copyright © International Astronomical Union 2008

References

Ferrarotti, A. S. & Gail, H.-P., 2006, A&A, 447, 553Google Scholar
Fryxell, B., Olson, K., Ricker, P., Timmes, F. X., & Zingale, M., et al. , 2000, ApJ, 131, 273Google Scholar
Freytag, B. & Höfner, S., 2008, A&A, 483, 571Google Scholar
Helling, Ch., Winters, J. M., & Sedlmayr, E, 2000, A&A, 358, 651Google Scholar
Helling, Ch. & Woitke, P., 2006, A&A, 455, 325Google Scholar
Helling, Ch., Woitke, P., & Thi, W.-F., 2008, A&A accepted, astro-ph 0803.4315v1Google Scholar
Höfner, S., Gautschy-Loidl, R., Aringer, B., & J/orgensen, U. G., 2003, A&A, 399, 589Google Scholar
Höfner, S. & Andersen, A. C., 2007, A&A, 465, L39Google Scholar
Hony, S. & Bouwman, J., 2004, A&A, 413, 981Google Scholar
Jäger, C., Mutschke, H., Dorschner, J., & Henning, Th., 1998, A&A, 332, 291Google Scholar
Jørgensen, U. G., Johnson, H. R., & Nordlund, Å, 1992, A&A, 261, 263Google Scholar
Jeong, K. S., Winters, J. M., Le Bertre, T., & Sedlmayr, E., 2003, A&A, 407, 191Google Scholar
Mattsson, L., Höfner, S., Wahlin, R., & Herwig, F., 2007 astro-ph 0705.2315v2CrossRefGoogle Scholar
Monnier, J. D., Millan-Gabet, R., & Tuthill, P. G., et al. , 2004, ApJ, 605, 436CrossRefGoogle Scholar
Niccolini, G., Woitke, P., & Lopez, B., 2003, A&A, 399, 703Google Scholar
Ramstedt, S., Schoeier, F. L., & Olofsson, H., 2007, astro-ph 0706.2559v1Google Scholar
Sandin, C., & Höfner, S., 2003, A&A, 404, 789Google Scholar
Schirrmacher, V., Woitke, P., & Sedlmayr, E., 2003, A&A, 404, 267Google Scholar
Gail, H.-P., & Sedlmayr, E., 1988, A&A, 206, 153Google Scholar
Verhoelst, T., Decin, L., van Malderen, R., Hony, S., Cami, J., Eriksson, K., Perrin, G., Deroo, P., Vandenbussche, B., & Waters, L. B. F. M., 2006, A&A, 447, 311Google Scholar
Winters, J. M., Le Bertre, T., Jeong, K. S., Helling, Ch., & Sedlmayr, E., 2000, A&A, 361, 641Google Scholar
Woitke, P., 1999, in Astronomy with Radioactivities, ed. Diehl, R. & Hartmann, D. (Schloß Ringberg, Germany: MPE Report 274), 163–174Google Scholar
Woitke, P., 2006a, A&A, 452, 537Google Scholar
Woitke, P., 2006b, A&A, 460, L9Google Scholar
Woitke, P., 2008, “Monte Carlo Radiative Transfer from τ = 0 to τ = ∞”, MNRAS, in preparationGoogle Scholar