Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-04T19:22:04.007Z Has data issue: false hasContentIssue false
  • English
  • Français

AKARI near-infrared spectroscopy: Detection of H2O and CO2 ices toward young stellar objects in the Large Magellanic Cloud

Published online by Cambridge University Press:  01 July 2008

Takashi Shimonishi ,
Takashi Onaka ,
Daisuke Kato ,
Itsuki Sakon ,
Yoshifusa Ita ,
Akiko Kawamura  and
Hidehiro Kaneda
Takashi Shimonishi
Affiliation:
Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0003, Japan, email: [email protected]
Takashi Onaka
Affiliation:
Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0003, Japan, email: [email protected]
Daisuke Kato
Affiliation:
Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0003, Japan, email: [email protected]
Itsuki Sakon
Affiliation:
Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0003, Japan, email: [email protected]
Yoshifusa Ita
Affiliation:
National Astronomical Observatory of Japan, Japan
Akiko Kawamura
Affiliation:
Department of Astrophysics, Nagoya University, Japan
Hidehiro Kaneda
Affiliation:
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Japan
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 first results of the AKARI Infrared Camera near-infrared spectroscopic survey of the Large Magellanic Cloud (LMC). The circumstellar material of young stellar objects (YSOs) are affected by galactic environments such as a metallicity or radiation field. Ices control the chemical balance of circumstellar environments of embedded YSOs. We detected absorption features of the H2O ice 3.05 μm and the CO2 ice 4.27 μm stretching mode toward seven massive YSOs in the LMC. This is the first detection of the 4.27 μm CO2 ice feature toward extragalactic YSOs. The present samples are for the first time spectroscopically confirmed to be YSOs. We used a curve-of-growth method to evaluate the column densities of the ices and derived the CO2/H2O ratio to be 0.45±0.17. This is clearly higher than that seen in Galactic massive YSOs (0.17±0.03). We suggest that the strong ultraviolet radiation field and/or the high dust temperature in the LMC may be responsible for the observed high CO2 ice abundance.

Keywords

circumstellar matterstars: pre-main-sequenceISM: moleculesgalaxies: individual (LMC)Magellanic Clouds
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 4 , Symposium S256: The Magellanic System: Stars, Gas, and Galaxies , July 2008 , pp. 233 - 238
Copyright
Copyright © International Astronomical Union 2009

References

Alves, D. R. 2004, New Astron. Revs, 48, 659CrossRefGoogle Scholar
Bernstein, M. P., Sandford, S. A., & Allamandola, L. J. 2000, ApJ, 542, 892CrossRefGoogle Scholar
Boogert, A. C. A. & Ehrenfreund, P. 2004, in Witt, A. N., Clayton, G. C., & Draine, B. T. (eds.), Astrophysics of Dust, ASP-CS, 309, p. 547Google Scholar
Boogert, A. C. A., Pontoppidan, K. M., Knez, C., et al. 2008, ApJ, 678, 985CrossRefGoogle Scholar
Chiar, J. E., Gerakines, P. A., Whittet, D. C. B., Pendleton, Y. J., Tielens, A. G. G. M., Adamson, A. J., & Boogert, A. C. A. 1998, ApJ, 498, 716CrossRefGoogle Scholar
Ehrenfreund, P., Boogert, A. C. A., Gerakines, P. A., Jansen, D. J., Schutte, W. A., Tielens, A. G. G. M., & van Dishoeck, E. F. 1996, A&A, 315, L341Google Scholar
Ehrenfreund, P. & Schutte, W. A. 2000, Adv. Sp. Res., 25, 2177CrossRefGoogle Scholar
Gerakines, P. A., Schutte, W. A., Greenberg, J. M., & van Dishoeck, E. F. 1995, A&A, 296, 810Google Scholar
Gerakines, P. A., Whittet, D. C. B., Ehrenfreund, P., et al. 1999, ApJ, 522, 357CrossRefGoogle Scholar
Gibb, E. L., Whittet, D. C. B, Schutte, W. A., et al. 2000, ApJ, 536, 347CrossRefGoogle Scholar
Gibb, E. L., Whittet, D. C. B., Boogert, A. C. A., & Tielens, A. G. G. M. 2004, ApJS, 151, 35CrossRefGoogle Scholar
Israel, F. P., de Graauw, Th., van de Stadt, D., & de Vries, C. P. 1986, ApJ, 303, 186CrossRefGoogle Scholar
Ita, Y., Onaka, T., Kato, D., et al. 2008, PASJ, 60, S435CrossRefGoogle Scholar
Kato, D., Nagashima, C., Nagayama, T., et al. 2007, PASJ, 59, 615CrossRefGoogle Scholar
Luck, R. E., Moffett, T. J., Barnes, T. G. III, & Gieren, P. W. 1998, AJ, 115, 605CrossRefGoogle Scholar
Meixner, M., Gordon, K. D., Indebetouw, R., et al. 2006, AJ, 132, 2268CrossRefGoogle Scholar
Murakami, H., Baba, H., Barthel, P., et al. 2007, PASJ, 59, S369CrossRefGoogle Scholar
Nummelin, A., Whittet, D. C. B., Gibb, E. L., Gerakines, P. A., & Chiar, J. E. 2001, ApJ, 558, 185CrossRefGoogle Scholar
Öberg, K. I., Fraser, H. J., Boogert, A. C. A., Bisschop, S. E., Fuchs, G. W., van Dishoeck, E. F., & Linnartz, H. 2007, A&A, 462, 1187Google Scholar
Ohyama, Y., Onaka, T., Matsuhara, H., et al. 2007, PASJ, 59, S411CrossRefGoogle Scholar
Onaka, T., Matsuhara, H., Wada, T., et al. 2007, PASJ, 59, S401CrossRefGoogle Scholar
Pontoppidan, K. M., Boogert, A. C. A., Fraser, H. J., et al. 2008, ApJ, 678, 1005CrossRefGoogle Scholar
Ruffle, D. P. & Herbst, E. 2001, MNRAS, 324, 1054CrossRefGoogle Scholar
Sakon, I., Onaka, T., Kaneda, H., et al. 2006, ApJ, 651, 174CrossRefGoogle Scholar
Shimonishi, T., Onaka, T., Kato, D., Sakon, I., Ita, Y., Kawamura, A., & Kaneda, H. 2008, ApJ, 686, L99CrossRefGoogle Scholar
Sylvester, R. J., Kemper, F., Barlow, M. J., de Jong, T., Waters, L. B. F. M., Tielens, A. G. G. M., & Omont, A. 1999, A&A, 352, 587Google Scholar
van Loon, J. Th., Oliveira, J. M., Wood, P. R., et al. 2005, MNRAS, 364, L71CrossRefGoogle Scholar
Watanabe, N., Mouri, O., Nagaoka, A., Chigai, T., Kouchi, A., & Pirronello, V. 2007, ApJ, 668, 1001CrossRefGoogle Scholar
Whitney, B. A., Indebetouw, R., Bjorkman, J. E., & Wood, K. 2004, ApJ, 617, 1177CrossRefGoogle Scholar
Whitney, B. A., Sewilo, M., Indebetouw, R., et al. 2008, AJ, 136, 18CrossRefGoogle Scholar
Whittet, D. C. B., Shenoy, S. S., Bergin, E. A., Chiar, J. E., Gerakines, P. A., Gibb, E. L., Melnick, G. J., & Neufeld, D. A. 2007, ApJ, 655, 332CrossRefGoogle Scholar
Zaritsky, D., Harris, J., Thompson, I. B., & Grebel, E. K. 2004, AJ, 128, 1606CrossRefGoogle Scholar