Hostname: page-component-848d4c4894-nmvwc Total loading time: 0 Render date: 2024-06-27T01:57:09.365Z Has data issue: false hasContentIssue false
  • English
  • Français

Modeling CO, CO2 and H2O Ice Abundances in the Envelopes of Young Stellar Objects in the Magellanic Clouds

Published online by Cambridge University Press:  04 September 2018

Tyler Pauly Open the ORCID record for Tyler Pauly [Opens in a new window]  and
Robin T. Garrod
Tyler Pauly
Affiliation:
Cornell Center for Astrophysics and Planetary Science and Department of Astronomy, Cornell University, Ithaca, NY 14853, USA email: tap74@cornell.edu
Robin T. Garrod
Affiliation:
Departments of Chemistry and Astronomy, University of Virginia, Charlottesville, VA 22904-4319, USA
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.

Massive young stellar objects (MYSOs) in the Magellanic Clouds (MCs) show infrared absorption features corresponding to significant abundances of CO, CO2 and H2O ice along the line of sight, with the relative abundances of these ices varying between sources in the Magellanic Clouds and the Milky Way. We use our gas-grain chemical code MAGICKAL, with multiple grain sizes and grain temperatures, and further expand it with a treatment for increased interstellar radiation field intensity to model the elevated dust temperatures observed in the MCs. We also adjust the elemental abundances used in the chemical models, guided by observations of HII regions in these metal-poor satellite galaxies. With a grid of models, we are able to reproduce the relative ice fractions observed in MC MYSOs, indicating that metal depletion and elevated grain temperature are important drivers of the MYSO envelope ice composition. The observed shortfall in CO in the Small Magellanic Cloud can be explained by a combination of reduced carbon abundance and increased grain temperatures. The models indicate that a large variation in radiation field strength is required to match the range of observed LMC abundances.

Keywords

astrochemistry—ISM: abundances—ISM: molecules—Magellanic Clouds
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 13 , Symposium S332: Astrochemistry VII: Through the Cosmos from Galaxies to Planets , March 2017 , pp. 47 - 53
Copyright
Copyright © International Astronomical Union 2018 

References

Boogert, A. C. A. & Ehrenfreund, P., 2004, ASPC, 309, 547Google Scholar
Cuppen, H. M., van Dishoeck, E. F., Herbst, E., & Tielens, A. G. G. M., 2009, A&A, 508, 275Google Scholar
Garrod, R. T., 2008, A&A, 491, 239Google Scholar
Garrod, R. T. & Pauly, T., 2011, ApJ, 735, 15Google Scholar
Garrod, R. T., 2013, ApJ, 765, 60Google Scholar
Gerakines, P. A., Whittet, D. C. B., Ehrenfreund, P., Boogert, A. C. A., Tielens, A. G. G. M., Schutte, W. A., Chiar, J. E., van Dishoeck, E. F., Prusti, T., Helmich, F. P., & de Graauw, T., 1999, ApJ, 522, 357Google Scholar
Gibb, E. L., Whittet, D. C. B., Schutte, W. A., Boogert, A. C. A., Chiar, J. E., Ehrenfreund, P., Gerakines, P. A., Keane, J. V., Tielens, A. G. G. M., van Dishoeck, E. F., & Kerkhof, O., 2000, ApJ, 536, 347Google Scholar
Gibb, E. L., Whittet, D. C. B., Boogert, A. C. A., & Tielens, A. G. G. M., 2004, ApJS, 151, 35Google Scholar
Harper, M., Weinstein, B., Simon, C., chebee7 i, Swanson-Hysell, N., The Gitter Badger, Greco, M., & Zuidhof, G. 2015, doi = 10.5281/zenodo.34938Google Scholar
Kurt, C. M. & Dufour, R. J., 1998, RMxAC, 7, 202Google Scholar
Oliveira, J. M., van Loon, J. T., Sloan, G. C., Indebetouw, R., Kemper, F., Tielens, A. G. G. M., Simon, J. D., Woods, P. M., & Meixner, M., 2011, MNRAS, 411, 36Google Scholar
Oliveira, J. M., van Loon, J. T., Sloan, G. C., Sewiło, M., Kraemer, K. E., Wood, P. R., Indebetouw, R., Filipović, M. D., Crawford, E. J., Wong, G. F., Hora, J. L., Meixner, M., Robitaille, T. P., Shiao, B., & Simon, J. D., 2013, MNRAS, 428, 3001Google Scholar
Pauly, T. & Garrod, R. T. 2016, ApJ, 817, 146Google Scholar
Peimbert, A. 2003, ApJ, 584, 735Google Scholar
Russell, S. C. & Dopita, M. A. 1992, ApJ, 384, 508Google Scholar
Shimonishi, T., Onaka, T., Kato, D., Sakon, I., Ita, Y., Kawamura, A., & Kaneda, H., 2010, A&A, 514, 12Google Scholar
Shimonishi, T., Dartois, E., Onaka, T., & Boulanger, F. 2016, A&A 585 107Google Scholar
Shimonishi, T., Onaka, T., Kawamura, A., & Aikawa, Y. 2016, ApJ, 827, 72Google Scholar
Watanabe, N. & Kouchi, A. 2002, ApJL, 571, 173Google Scholar
Zucconi, A., Walmsley, C. M., & Galli, D. 2001, A&A, 376, 650Google Scholar