Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-13T09:23:47.715Z Has data issue: false hasContentIssue false

Submillimeter H2O maser emission from water fountain nebulae

Published online by Cambridge University Press:  16 July 2018

Daniel Tafoya
Affiliation:
Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden email: daniel.tafoya@chalmers.se
Wouter H. T. Vlemmings
Affiliation:
Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden email: daniel.tafoya@chalmers.se
Andres F. Pérez-Sánchez
Affiliation:
European Southern Observatory, Alonso de Córdova 3107, Vitacura, Casilla 19001, Santiago, Chile
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.

We present the results of the first detection of submillimeter water maser emission toward water-fountain nebulae. Using APEX we found emission at 321.226 GHz toward two sources: IRAS 18043−2116, and IRAS 18286−0959. The submillimeter H2O masers exhibit expansion velocities larger than those of the OH masers, suggesting that these masers, similarly to the 22 GHz masers, originate in fast bipolar outflows. The 321 GHz masers in IRAS 18043−2116 and IRAS 18286−0959, which figure among the sources with the fastest H2O masers, span a velocity range similar to that of the 22 GHz masers, indicating that they probably coexist. The intensity of the submillimeter masers is comparable to the 22 GHz masers, implying that the kinetic temperature of the region where the masers originate is Tk>1000 K. We propose a simple model invoking the passage of two shocks through the same gas that creates the conditions for explaining the strong high-velocity 321 GHz masers coexisting with the 22 GHz masers in the same region.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2018 

References

Cooke, B. & Elitzur, M., 1985, ApJ, 295, 175CrossRefGoogle Scholar
Deacon, R. M., Chapman, J. M., Green, A. J., & Sevenster, M. N., 2007, ApJ, 658, 1096CrossRefGoogle Scholar
Elitzur, M., Hollenbach, D. J., & McKee, C. F., 1989, ApJ, 346, 983CrossRefGoogle Scholar
Imai, H., Obara, K., Diamond, P. J., Omodaka, T., & Sasao, T., 2002, Nature, 417, 829CrossRefGoogle Scholar
Kaufman, M. J. & Neufeld, D. A., 1996, ApJ, 456, 250CrossRefGoogle Scholar
Likkel, L. & Morris, M., 1988, ApJ, 329, 914CrossRefGoogle Scholar
Melnick, G. J., Menten, K. M., Phillips, T. G., & Hunter, T., 1993, ApJ (Letters), 416, L37CrossRefGoogle Scholar
Menten, K. M., Melnick, G. J., & Phillips, T. G., 1990a, ApJ (Letters), 350, L41CrossRefGoogle Scholar
Menten, K. M., Melnick, G. J., Phillips, T. G., & Neufeld, D. A., 1990b, ApJ (Letters), 363, L27CrossRefGoogle Scholar
Neufeld, D. A. & Melnick, G. J., 1990, ApJ (Letters), 352, L9CrossRefGoogle Scholar
Patel, N. A., Curiel, S., Zhang, Q.,et al. 2007, ApJ (Letters), 658, L55CrossRefGoogle Scholar
Pérez-Sánchez, A. F., Tafoya, D., García López, R., Vlemmings, W., & Rodríguez, L. F., 2017, A&A, 601, A68Google Scholar
Richards, A. M. S., Etoka, S., Gray, M. D.,et al. 2012, A&A, 546, A16Google Scholar
Tafoya, D., Franco-Hernández, R., Vlemmings, W. H. T., Pérez-Sánchez, A. F., & Garay, G., 2014, A&A, 562, L9Google Scholar
Vlemmings, W. H. T., Diamond, P. J., & Imai, H., 2006, Nature, 440, 58CrossRefGoogle Scholar
Walsh, A. J., Breen, S. L., Bains, I., & Vlemmings, W. H. T., 2009, MNRAS, 394, L70CrossRefGoogle Scholar
Yates, J. A., Field, D., & Gray, M. D., 1997, MNRAS, 285, 303CrossRefGoogle Scholar
Yung, B. H. K., Nakashima, J.-i., Imai, H., et al. 2011, ApJ, 741, 94CrossRefGoogle Scholar