Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-26T04:07:39.951Z Has data issue: false hasContentIssue false

AGB circumstellar envelopes: molecular observations

Published online by Cambridge University Press:  25 May 2016

V. Bujarrabal*
Affiliation:
Observatorio Astronómico Nacional, Apartado 1143, E-28800 Alcalá de Henares, Spain

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.

Due to the low excitation requirements and easy observation from the ground, molecular line observations probably constitute our main source of empirical knowledge on circumstellar envelopes (CSEs) around AGB stars. The CO rotational transitions, the most intense ‘thermal’ lines, are efficiently used to determine the total gas content and its spatial distribution in wide samples of objects. Thermal emission from other molecules is mainly useful in order to study their abundances and the chemical reactions taking place in CSEs. Maser lines are easily observed due to their high intensity and the flux distribution in very compact spatial spots and narrow profile spikes, characteristic of the exponential amplification; however the data interpretation is difficult due to the intricate pumping processes. The most important maser lines (of SiO, H2O and OH) arise from very different regions, which allows the study of various components of the CSEs. We will focus here on SiO masers.

Type
Part 4. Circumstellar Envelopes
Copyright
Copyright © Astronomical Society of the Pacific 1999 

References

Alcolea, J., Bujarrabal, V., Gómez-González, J., 1990, A&A 231, 431 Google Scholar
Alcolea, J., Pardo, J.R., Bujarrabal, V., et al., 1999, A&AS, submitted Google Scholar
Bieging, J.H., Knee, L.B.G., Latter, W.B., Olofsson, H., 1998, A&A 339, 811 Google Scholar
Bujarrabal, V., 1994, A&A 285, 953 Google Scholar
Bujarrabal, V., Fuente, A., Omont, A., 1994a, A&A 285, 247 Google Scholar
Bujarrabal, V., Fuente, A., Omont, A., 1994b, ApJ 421, L47 CrossRefGoogle Scholar
Bujarrabal, V., Planesas, P., Del Romero, A., 1987, A&A 175, 164 Google Scholar
Bujarrabal, V., Gómez-González, J., Planesas, P., 1989, A&A 219, 256 Google Scholar
Cernicharo, J., Bujarrabal, V., 1992, ApJ 401, L109 CrossRefGoogle Scholar
Cernicharo, J., Bujarrabal, V., Santarén, J.L., 1993, ApJ 407, L33 CrossRefGoogle Scholar
Cernicharo, J., Guélin, M., 1987, A&A 183, L10 Google Scholar
Clark, F.O, Troland, T.H., Miller, J.S., 1985, ApJ 289, 756 CrossRefGoogle Scholar
Colomer, F., Graham, D.A., Krichbaum, T.P., et al., 1992, A&A 254, L17 Google Scholar
Doel, R.C., Gray, M.D., Humphreys, E.M.L., et al., 1995, A&A 302, 797 Google Scholar
Fuente, A., Cernicharo, J., Omont, A., 1998, A&A 330, 232 Google Scholar
Goldreich, P., Scoville, N., 1976, ApJ 205, 144 CrossRefGoogle Scholar
Groenewegen, M.A.T., 1994, A&A 290, 531 Google Scholar
Groenewegen, M.A.T., van der Veen, W.E.C.J., Matthews, H.E., 1998, A&A 338, 491 Google Scholar
Guélin, M., Forestini, M., Valiron, P., et al., 1995, A&A 297, 183 Google Scholar
Habing, H.J., 1996, A&A Rev 7, 97 Google Scholar
Hall, P.J., Allen, D.A., Troup, D.R., et al., 1990, MNRAS 243, 480 Google Scholar
Izumiura, H., Deguchi, T., Hashimoto, O, et al., 1995, ApJ 453, 837 CrossRefGoogle Scholar
Jewell, P.R., Dickinson, D.F., Snyder, L.E., Clemens, D.P., 1987, ApJ 323, 749 CrossRefGoogle Scholar
Justtanont, K., Skinner, C.J., Tielens, A.G.G.M., 1994, ApJ 435, 852 CrossRefGoogle Scholar
Justtanont, K., Skinner, C.J., Tielens, A.G.G.M., et al., 1996, ApJ 456, 337 CrossRefGoogle Scholar
Kahane, C., Cernicharo, J., Gómez-González, J., Guélin, M., 1992, A&A 256, 235 Google Scholar
Kastner, J.H., 1992, ApJ 401, 337 CrossRefGoogle Scholar
Kerschbaum, F., Olofsson, H., Hron, J., 1996, A&A 311, 273 Google Scholar
Kerschbaum, F., Olofsson, H., 1998, A&A 336, 654 Google Scholar
Knapp, G.R., Morris, M., 1985, ApJ 292, 640 CrossRefGoogle Scholar
Knapp, G.R., Young, K., Lee, E., Jorissen, A., 1998, ApJS 117, 209 CrossRefGoogle Scholar
Kwan, J., Linke, R.A., 1982, ApJ 254, 587 CrossRefGoogle Scholar
Kwan, J., Scoville, N., 1974, ApJ 194, L97 CrossRefGoogle Scholar
Lafont, S., Lucas, R., Omont, A., 1982, A&A 106, 201 Google Scholar
Lockett, P., Elitzur, M., 1992, ApJ 399, 704 CrossRefGoogle Scholar
Loup, C., Forveille, T., Omont, A., Paul, J.F., 1993, A&AS 99, 291 Google Scholar
Lucas, R., Bujarrabal, V., Guilloteau, S., et al., 1992, A&A 262, 491 Google Scholar
Mamon, G.A., Glassgold, A.E., Huggins, P.J., 1988, ApJ 328, 797 CrossRefGoogle Scholar
Margulis, M., Van Blerkom, D.J., Snell, R.L., Kleinmann, S.G., 1990, ApJ 361, 673 CrossRefGoogle Scholar
Miyoshi, M., Matsumoto, K., Kameno, S., et al., 1994, Nature 371, 395 CrossRefGoogle Scholar
Morris, M., 1975, ApJ 197, 603 CrossRefGoogle Scholar
Nercessian, E. Guilloteau, S., Omont, A., Benayoun, J.J., 1989, A&A 210, 225 Google Scholar
Neri, R., Kahane, C., Lucas, R., Bujarrabal, V., Loup, C., 1998, A&AS 130, 1 Google Scholar
Nyman, L.-Å., Hall, P.J., Le Bertre, T., 1993a, A&A 280, 551 Google Scholar
Nyman, L.-Å., Olofsson, H., Johansson, L.E.B., et al., 1993b, A&A 269, 377 Google Scholar
Olofsson, H., Bergman, P., Lucas, R., et al., 1998a, A&A 330, L1 Google Scholar
Olofsson, H., Eriksson, K., Gustafsson, B., Carlström, U., 1993a, ApJS 87, 267 CrossRefGoogle Scholar
Olofsson, H., Eriksson, K., Gustafsson, B., Carlström, U., 1993b, ApJS 87, 305 CrossRefGoogle Scholar
Olofsson, H., Johansson, L.E.B., Hjalmarson, Å, Nguyen-Q-Rieu, , 1982, A&A 107, 128 Google Scholar
Olofsson, H., Lindqvist, M., Nyman, L.-Å., Winnberg, A., 1998b, A&A 329, 1059 Google Scholar
Omont, A., Loup, C., Forveille, T., et al., 1993a, A&A 267, 515 Google Scholar
Omont, A., Lucas, R., Morris, M., Guilloteau, S., 1993b, A&A 267, 490 Google Scholar
Sahai, R., Wannier, P.G., 1992, ApJ 394, 320 CrossRefGoogle Scholar
Stanek, K.Z., Knapp, G.R., Young, K., Phillips, T.G., 1995, ApJS 100, 169 CrossRefGoogle Scholar
Young, K., 1995, ApJ 445, 872 CrossRefGoogle Scholar