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High-Density, Cool Regions of Interstellar Matter in the Galaxy

Published online by Cambridge University Press:  14 August 2015

W. B. Burton  and
H. S. Liszt
W. B. Burton
Affiliation:
Department of Astronomy, University of Minnesota
H. S. Liszt
Affiliation:
National Radio Astronomy Observatory

Extract

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The distribution of interstellar nucleons is dominated by gas at temperatures ranging from a few K to a few hundred K. At the warmer end of this temperature range, the gas is predominantly in the form of ubiquitously distributed atomic hydrogen. The colder gas is almost entirely molecular; it resides in compressed clumps, confined principally to the inner-galaxy, and is most effectively traced by observations of carbon monoxide. In this paper, we focus on some of the problems which currently hinder derivation of the morphology and total number of nucleons in the galaxy. For the atomic gas, these problems involve optical depth effects in HI profiles, the amount of cold HI residing in molecular clouds, and the form of the outer-galaxy rotation curve. For the molecular gas, the problems involve the uncertainties in the conversion from CO intensities to H2 densities, including the possibility of composition gradients across the galaxy, the total number and typical size of molecular clouds, and the possibility that the molecular material in the region of the galactic nucleus is distributed differently from the material in the galaxy at large.

Type
Research Article
Information
Symposium - International Astronomical Union , Volume 94: Origin of Cosmic Rays , 1981 , pp. 227 - 250
Copyright
Copyright © Reidel 1981 

References

Altenhoff, W. J., Downes, D., Goad, L., Maxwell, A., and Rinehart, R.: 1970, Astr. and Astrophys. Suppl. 1, pp. 319–355.Google Scholar
Baker, P. L.: 1976, Astr. and Astrophys. 48, pp. 163–164.Google Scholar
Baker, P. L.: 1979, Proc. IAU Symp. 84, pp. 287–294.Google Scholar
Baker, P. L., and Burton, W. B.: 1975, Astrophys. J. 198, pp. 281–297.Google Scholar
Baker, P. L., and Burton, W. B.: 1979, Astr. and Astrophys. Suppl. 35, pp. 129–152.Google Scholar
Blitz, L.: 1979, Astrophys. J. Lett. 231, pp. L115–L119.Google Scholar
Blitz, L., and Shu, F.: 1980, Astrophys. J., in press.Google Scholar
Burton, W. B.: 1972, Astr. and Astrophys. 19, pp. 51–65.Google Scholar
Burton, W. B.: 1976, Ann. Rev. Astr. and Astrophys. 14, pp. 275–306.Google Scholar
Burton, W. B., and Gordon, M. A.: 1976, Astrophys. J. Lett. 207, pp. L89–L93.Google Scholar
Burton, W. B., and Gordon, M. A.: 1978, Astr. and Astrophys. 63, pp. 7–27.Google Scholar
Burton, W. B., Liszt, H. S., and Baker, P. L.: 1978, Astrophys. J. Lett. 219, pp. L67–L72.CrossRefGoogle Scholar
Clark, B. G.: 1965, Astrophys. J. 142, pp. 1398–1422.Google Scholar
Cohen, R. S., Tomasevich, G. R., and Thaddeus, P.: 1979, Proc. IAU Symp. 84, pp. 53–56.Google Scholar
Cohen, R. S., Cong, H., Dame, T. M., and Thaddeus, P.: 1980, Astrophys. J. Lett., in press.Google Scholar
Davies, R. D.: 1956, Mon. Not. Roy. Astr. Soc. 116, pp. 443–452.CrossRefGoogle Scholar
de Ruiter, H. R., Willis, A. G., and Arp, H. C.: 1977, Astr. and Astrophys. Suppl. 28, pp. 211–293.Google Scholar
Field, G. B., Goldsmith, D. W., and Habing, H. J.: 1969, Astrophys. J. 158, pp. 173–183.Google Scholar
Gordon, M. A., and Burton, W. B.: 1976, Astrophys. J. 208, pp. 346–353.Google Scholar
Heeschen, D. W.: 1955, Astrophys. J. 121, pp. 569–584.CrossRefGoogle Scholar
Heiles, C.: 1975, Astr. and Astrophys. Suppl. 20, pp. 37–55.Google Scholar
Heiles, C.: 1980, Astrophys. J. 235, pp. 833–839.Google Scholar
Jackson, P. D., FitzGerald, M. P., and Moffat, A. F. J.: 1979, Proc. IAU Symp. 84, pp. 221–224.Google Scholar
Johansson, L. E. B., Andersson, C., Goss, W. M., and Winnberg, A.: 1977, Astr. and Astrophys. 54, pp. 323–334.Google Scholar
Kalberla, P. M. W.: 1978, , University of Bonn.Google Scholar
Knapp, G. R., Tremaine, S. D., and Gunn, J. E.: 1978, Astr. J. 83, pp. 1585–1593.Google Scholar
Kniffen, D. A., Fichtel, C. E., and Thompson, D. J.: 1977, Astrophys. J. 215, pp. 765–774.Google Scholar
Linke, R. A., Stark, A. A., and Frerking, M. A.: 1980, Astrophys. J., in press.Google Scholar
Liszt, H. S., and Burton, W. B.: 1978, Astrophys. J. 226, pp. 790–816.Google Scholar
Liszt, H. S., and Burton, W. B.: 1980a, Astrophys. J. 236, pp. 779–797.Google Scholar
Liszt, H. S., and Burton, W. B.: 1980b, Astrophys. J., in press.Google Scholar
Liszt, H. S., Burton, W. B., and Bania, T. M.: 1980, Astrophys. J., submitted.Google Scholar
Liszt, H. S., Burton, W. B., and Xiang, D.-L.: 1980, Astrophys. J., in preparation.Google Scholar
Liszt, H. S., Burton, W. B., Sanders, R. H., and Scoville, N. Z.: 1977, Astrophys. J. 213, pp. 38–42.Google Scholar
Lockman, F. J.: 1976, Astrophys. J. 209, pp. 429–444.Google Scholar
Lockman, F. J.: 1979, Astrophys. J. 232, pp. 761–781.Google Scholar
Radhakrishnan, V., Murray, J. D., Lockhart, P., and Whittle, R. P. J.: 1972, Astrophys. J. Suppl. 24, pp. 15–47.Google Scholar
Roberts, W. W., and Burton, W. B.: 1977, in “Topics in Interstellar Matter,” ed. van Woerden, H. (Dordrecht: Reidel), pp. 195–205.Google Scholar
Scoville, N. Z., and Solomon, P. M.: 1975, Astrophys. J. Lett. 199, pp. L105–L109.Google Scholar
Scoville, N. Z., Solomon, P. B., and Sanders, D. B.: 1979, Proc. IAU Symp. 84, pp. 277–283.Google Scholar
Shuter, W. L. H., and Verschuur, G. L.: 1964, Mon. Not. Roy. Astr. Soc. 127, pp. 387–404.Google Scholar
Solomon, P. M., and Sanders, D. B.: 1980, in “Giant Molecular Clouds in the Galaxy,” eds. Solomon, P. M. and Edmunds, M. (London: Pergamon).Google Scholar
Solomon, P. M., and Wickramasinghe, N. C.: 1969, Astrophys. J. 158, pp. 449–460.Google Scholar
Solomon, P. M., Sanders, D. B., and Scoville, N. Z.: 1979, Proc. IAU Symp. 84, pp. 35–52.Google Scholar
Solomon, P. M., Scoville, N. Z., and Sanders, D. B.: 1979, Astrophys. J. Lett. 232, pp. L89–L93.Google Scholar
Spitzer, L., and Schwarzschild, M.: 1951, Astrophys. J. 114, pp. 385–397.Google Scholar
Spitzer, L., and Schwarzschild, M.: 1953, Astrophys. J. 118, pp. 106–112.CrossRefGoogle Scholar
Stark, A. A.: 1979, , Princeton University.Google Scholar
Stark, A. A., and Blitz, L.: 1978, Astrophys. J. Lett. 225, pp. L15–L19.CrossRefGoogle Scholar
Szabo, A., Shuter, W. L. H., and McCutcheon, W.: 1980, Astrophys. J. 235, pp. 45–51.Google Scholar
van de Hulst, H. C., Muller, C. A., and Oort, J. H.: 1954, Bull. Astr. Inst. Netherlands 12, pp. 117–149.Google Scholar
van der Hulst, J. M.: 1979, Astr. and Astrophys. 75, pp. 97–111.Google Scholar
Wannier, P. G., Penzias, A. A., Linke, R. A., and Wilson, R. W.: 1976, Astrophys. J. 204, pp. 26–42.CrossRefGoogle Scholar
Weaver, H., and Williams, D. R. W.: 1973, Astr. and Astrophys. Suppl. 8, pp. 1–503.Google Scholar
Zuckerman, B., and Kuiper, T. B. H.: 1980, Astrophys. J. 235, pp. 840–844.CrossRefGoogle Scholar