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Physical and Chemical Processes in the Diffuse and Dense Neutral ISM

Published online by Cambridge University Press:  20 December 2008

M.J. Kaufman*
Affiliation:
Dept. of Physics and Astronomy, San Jose State University, San Jose, CA 95192, USA
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Abstract

Most of the mass of the interstellar medium is in neutral phases that are heated by far-ultraviolet radiation from star forming regions. The gas, in turn, emits line radiation in the infrared and submillimeter that potentially has great diagnostic value. In this paper, we will review the physical processes (including heating, cooling, gas phase and grain surface chemistry) that give rise to this line emission and present diagnostic diagrams. We will also discuss several examples where models of neutral gas emission have been used to interpret line emission, including observations of H2O and O2 in molecular clouds and an example which points out the caution that must be used when applying the diagnostics to kiloparsec-sized regions in other galaxies.

Type
Research Article
Copyright
© EAS, EDP Sciences, 2009

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References

Bakes, E.L.O., & Tielens, A.G.G.M., 1994, ApJ, 427, 822 CrossRef
Bergin, E.A., Neufeld, D.A., & Melnick, G.J., 1998, ApJ, 499, 777 CrossRef
Bergin, E.A., et al., 2000, ApJ, 539, L129 CrossRef
Bertoldi, F., et al., 2003, A&A, 409, L47
Cazaux, S., & Tielens, A.G.G.M., 2004, ApJ, 604, 222 CrossRef
Contursi, A., et al., 2002, AJ, 124, 751 CrossRef
Dole, H., et al., 2006, A&A, 451, 417
Kaufman, M.J., Wolfire, M.G., & Hollenbach, D.J., 2006, ApJ, in press
Kaufman, M.J., Wolfire, M.G., Hollenbach, D.J., & Luhman, M.L., 1999, ApJ, 527, 795 (KWHL99) CrossRef
Langer, W.D., & Graedel, T.E., 1989, ApJS, 69, 241 CrossRef
Larsson, B., et al., 2007, A&A, 466, 999
Maiolino, R., Cox, P., Caselli, P., et al., 2005, A&A, 440, L51
Millar, T.J., 1990, Molec. Astrophys., 115
Neufeld, D.A., Lepp, S., & Melnick, G.J., 1995, ApJS, 100, 132 CrossRef
Neufeld, D.A., Kaufman, M.J., Goldsmith, P.F., Hollenbach, D.J., & Plume, R., 2002, ApJ, 580, 278 CrossRef
Oey, M.S., & Kennicutt, R.C. Jr., 1993, ApJ, 411, 137 CrossRef
Osterbrock, D.E., & Ferland, G.J., 2006, Astrophysics of gaseous nebulae and active galactic nuclei, 2nd. ed. D.E. Osterbrock and G.J. Ferland (Sausalito, C.A., University Science Books)
Parravano, A., Hollenbach, D.J., & McKee, C.F., 2003, ApJ, 584, 797 CrossRef
Plume, R., et al., 2004, ApJ, 605, 247 CrossRef
Smith, J.D.T., et al., 2004, ApJS, 154, 199 CrossRef
Snell, R.L., et al., 2000, ApJ, 539, L101 CrossRef
Weingartner, J.C., & Draine, B.T., 2001, ApJ, 563, 842 CrossRef
Wolfire, M.G., Hollenbach, D., & Tielens, A.G.G.M., 1993, ApJ, 402, 195 CrossRef
Wolfire, M., McKee, C.F, Hollenbach, D.J., & Tielens, A.G.G.M., 2003, ApJ, 587, 278 CrossRef
Wright, E.L., et al., 1991, ApJ, 381, 200 CrossRef