Skip to main content Accessibility help
×
Home

Determining the effect of a non-uniform AGB outflow on its chemistry

  • M. Van de Sande (a1), J. O. Sundqvist (a1), T. J. Millar (a2) and L. Decin (a1)

Abstract

The molecular composition of the stellar outflows of AGB stars is determined by the stellar elemental carbon-to-oxygen abundance ratio, together with the physical circumstances in the innermost region of the outflow. Near the stellar surface, thermal equilibrium (TE) can be assumed. This leads to a certain molecular composition with a O- or C-rich signature. However, several molecular species have been detected that are not expected to be present in the inner region under the assumption of TE chemistry. As a solution to explain the presence of these unexpected species, non-equilibrium chemistry in the inner region of the outflow has been proposed. The outflows of AGB stars are generally not spherically symmetric or homogeneous, which influences the penetration of interstellar UV photons throughout the outflow. We investigate the effect of a clumpy, non-homogeneous outflow on the composition of the inner region by introducing a simple porosity formalism in our chemical model.

Copyright

References

Hide All
Agúndez, M., Cernicharo, J., & Guélin, M., 2010, ApJ, 724, L133
Agúndez, M., Cernicharo, J., Quintana-Lacaci, G. et al., 2017, A&A, 601, A4
Bujarrabal, V., Fuente, A., & Omont, A., 1994, A&A, 285, 247
Cherchneff, I., 2006, A&A, 456, 1001
Decin, L., Agúndez, M., Barlow, M. J. et al., 2010, A&A, 467, 64
Duari, D., Cherchneff, I., & Willacy, K., 1999, A&A, 341, L47
Gobrecht, D., Cherchneff, I., Sarangi, A. et al., 2016, A&A, 585, A6
Justtanont, K., de Jong, T., Helmich, F. P. et al., 1996, A&A, 315, L127
Keady, J. J. & Ridgway, S. T., 1993, A&A, 564, A88
Kervella, P., Montargès, M., Ridgway, S. T. et al., 2014, ApJ, 406, 199
Khouri, T., Maercker, M., Waters, L. B. F. M. et al., 2016, A&A, 591, A70
Maercker, M., Mohamed, S., Vlemmings, W. H. T. et al., 1995, Nature, 490, 232
McElroy, D., Walsh, C., Markwick, A. J. et al., 2013, A&A, 550, A36
Menten, K. M. & Alcolea, J., 1995, ApJ, 448, 416
Omont, A., Lucas, R., Morris, M., & Guilloteau, S., 1993, A&A, 267, 490
Owocki, S. P., Gayley, K. G., & Shaviv, N. J., 2004, ApJ, 616, 525
Owocki, S. P. & Cohen, D. H., 2006, ApJ, 648, 565
Sundqvist, J. O., Owocki, S. P., Cohen, D. H. et al., 2012, MNRAS, 420, 1553
Sundqvist, J. O., Puls, J., & Owocki, S. P., 2014, A&A, 568, A59
MathJax
MathJax is a JavaScript display engine for mathematics. For more information see http://www.mathjax.org.

Keywords

Determining the effect of a non-uniform AGB outflow on its chemistry

  • M. Van de Sande (a1), J. O. Sundqvist (a1), T. J. Millar (a2) and L. Decin (a1)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed