천문학논총 (Publications of The Korean Astronomical Society)

  • 제22권4호
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  • Pages.89-95
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  • 2007
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  • 1225-1534(pISSN)
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  • 2287-6936(eISSN)
한국천문학회 (The Korean Astronomical Society)
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우리은하 중온 이온화 매질의 광이온화 모델

PHOTOIONIZATION MODELS OF THE WARM IONIZED MEDIUM IN THE GALAXY

  • 발행 : 2007.12.31
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초록

The warm ionized medium (WIM) outside classical H II regions is a fundamental gas-phase constituent of the Milky Way and other late-type spiral galaxies, and is traced by faint emission lines at optical wavelengths. We calculate the photoionization models of the WIM in the Galaxy by a stellar UV radiation with the effective temperature 35,000 K assuming not only spherical geometry but also plane parallel geometry, and compare the results with the observed emission line ratios. We also show the dependence of the emission line ratios on various gas-phase abundances. The emergent emission-line ratios are in agreement with the average-values of observed ratios of [S II] ${\lambda}6716/H{\alpha}$, [N II] ${\lambda}6583/H{\alpha}$, [O I] ${\lambda}6300/H{\alpha}$, [O III] ${\lambda}5007/H{\alpha}$, He I ${\lambda}5876/H{\alpha}$. However, their extreme values could not be explained with the photoionization models. It is also shown that the addition of all stellar radiation from the OB stars in the Hipparcos stellar catalog resembles that of an O7-O8 type star.

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참고문헌

  1. Abbott, D. C., 1982, The Return Of Mass And Energy To The Interstellar Medium By Winds From Early-Type Stars, ApJ, 263, 723
  2. Anders, E. & Grevesse, N., 1989, Abundances of the elements - Meteoritic and solar, Geochim. Cosmochim. Acta, 53, 197
  3. Baldwin, J., Ferland, G. J., Martin, P. G., Corbin, M., Cota, S., Peterson, B. M., & Slettebak, A., 1991, Physical conditions in the Orion Nebula and an assessment of its helium abundance, ApJ, 374, 580 https://doi.org/10.1086/170146
  4. Bohlin, R. C., Savage, B. D., & Drake, J. F., 1978, A Survey Of Interstellar H I From L-Alpha Absorption Measurements. Ii, ApJ, 224, 132
  5. Castelli, F. & Kurucz, R. L., 2003, New Grids of ATLAS9 Model Atmospheres, IAUS, 210, 20
  6. Cowie, L. L. & Songaila, A., 1986, High-resolution optical and ultraviolet absorption-line studies of interstellar gas, ARA&A, 24, 499
  7. Domgorgen, H. & Mathis, J. S., 1994, The ionization of the diffuse ionized gas, ApJ, 428, 647 https://doi.org/10.1086/174275
  8. Ferguson, A. M. N., Wyse, R. F. G., Gallagher, J. S. III, & Hunter, D. A., 1996, Diffuse Ionized Gas in Spiral Galaxies: Probing Lyman Continuum Photon Leakage From H II Regions?, AJ, 111, 2265
  9. Ferland, G. J., Korista, K. T., Verner, D. A., Ferguson, J. W., Kingdon, J. B., & Verner, E. M., 1998, CLOUDY 90: Numerical Simulation of Plasmas and Their Spectra, PASP, 110, 761
  10. Grevesse, N. & Noels, A., 1993, in Origin and Evolution of the Elements, ed. N. Prantzos, E. Vangioni-Flam, & M. Casse (Cambridge: Cambridge Univ. Press), 15
  11. Howk, J. C., Savage, B. D., & Fabian, D., 1999, Chandrasekhar & Fermi's Convergence of Astrophysics and Cosmic Rays, ApJ, 525, 253 https://doi.org/10.1086/307888
  12. Kilian-Montenbruck, J., Gehren, T., & Nissen, P. E., 1994, The galactic distribution of chemical elements as derived from B-stars in open clusters. 2: NGC 6611, S 285, and S 289, A&A, 291, 757
  13. Madsen, G. J., Reynolds, R. J., & Haffner, L. M., 2006, A Multiwavelength Optical Emission Line Survey of Warm Ionized Gas in the Galaxy, ApJ, 652, 401 https://doi.org/10.1086/508441
  14. Mathis, J. S., 1986, The photoionization of the diffuse galactic gas , ApJ, 301, 423 https://doi.org/10.1086/163910
  15. Mathis, J. S., 2000, The Warm Ionized Medium in the Milky Way and Other Galaxies, ApJ, 544, 347 https://doi.org/10.1086/317210
  16. Meyer, D. M., Cardelli, J. A., & Sofia, U. J., 1997, The Abundance of Interstellar Nitrogen, ApJ, 490, L103 https://doi.org/10.1086/311023
  17. Meyer, D. M., Jura, M., & Cardelli, J. A., 1998, The Definitive Abundance of Interstellar Oxygen, ApJ, 493, 222 https://doi.org/10.1086/305128
  18. Osterbrock, D. E., Tran, H. D., & Veilleux, S., 1992, Faint emission lines in the spectrum of the Orion Nebula and the abundances of some of the rarer elements, ApJ, 389, 305 https://doi.org/10.1086/171206
  19. Perryman, M. A. C., et al., 1997, The HIPPARCOS Catalogue, A&A, 323, L49
  20. Rand, R. J., 1996, Diffuse Ionized Gas in Nine Edgeon Galaxies, ApJ, 462, 712 https://doi.org/10.1086/177184
  21. Rand, R. J., 1998, Further Spectroscopy of the Diffuse Ionized Gas in NGC 891 and Evidence for a Secondary Source of Ionization, ApJ, 501, 137 https://doi.org/10.1086/305814
  22. Reynolds, R. J., 1984, A measurement of the hydrogen recombination rate in the diffuse interstellar medium, ApJ, 282, 191 https://doi.org/10.1086/162190
  23. Reynolds, R. J., 1991, Ionized disk/halo gas - Insight from optical emission lines and pulsar dispersion measures, IAUS, 144, 67
  24. Reynolds, R. J. & Tufte, S. L., 1995, A search for the He I lambda 5876 recombination line from the diffuse interstellar medium, ApJ, 439, L17 https://doi.org/10.1086/187734
  25. Rubin, R. H., Simpson, J. R., Haas, M. R., & Erickson, E. F., 1991, Axisymmetric model of the ionized gas in the Orion Nebula, ApJ, 374, 564 https://doi.org/10.1086/170145
  26. Savage, B. D., & Sembach, K. R., 1996, Interstellar Abundances from Absorption-Line Observations with the Hubble Space Telescope, ARA&A, 34, 279
  27. Sembach, K. R., Howk, J. C., Ryans, R. S. I., & Keenan, F. P., 2000, Modeling the Warm Ionized Interstellar Medium and Its Impact on Elemental Abundance Studies, ApJ, 528, 301
  28. Straizys, V. & Kuriliene, G., 1981, Fundamental stellar parameters derived from the evolutionary tracks, Ap&SS, 80, 353 https://doi.org/10.1007/BF00652936
  29. Sofia, U. J., Cardelli, J. A., Guerin, K. P., & Meyer, D. M., 1997, Carbon in the Diffuse Interstellar Medium, ApJ, 482, L105 https://doi.org/10.1086/310681
  30. Sokolowski, J. & Bland-Hawthorn, J., 1991, Photoionization of high-latitude gas in NGC 891, PASP, 103, 911
  31. van Hoof, P. A. M., Weingartner, J. C., Martin, P. G., Volk, K., & Ferland, G. J., 2004, Grain size distributions and photoelectric heating in ionized media, MNRAS, 350, 1330 https://doi.org/10.1111/j.1365-2966.2004.07734.x
  32. Walterbos, R. A. M. & Braun, R., 1996, The Cool and Warm Phases of the Interstellar Medium in Spiral Galaxies, ASPC, 106, 1