Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-25T20:26:14.481Z Has data issue: false hasContentIssue false
  • English
  • Français

Current Problems in 21 cm Line Studies of the Large-Scale Structure of the Galaxy

Published online by Cambridge University Press:  14 August 2015

W. B. Burton
W. B. Burton*
Affiliation:
National Radio Astronomy Observatory∗ Charlottesville, Va., U.S.A.

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.

A number of current problems in 21 cm line studies of the Galaxy as a whole are discussed. Because of the difficulties involved with straightforward mapping, it is important to isolate integrated and other properties of the hydrogen profiles, the interpretation of which does not require accurate distance determinations. In addition, methods of analysis are necessary which either account for or exploit the sensitivity of hydrogen profiles to velocity irregularities and to geometrical configurations. The model-fitting approach to the interpretation of the hydrogen profiles is useful in this respect. Extragalactic hydrogen studies which show the relative ordering of the various components of spiral structure can inspire research in our own Galaxy. Such investigations are necessary for an understanding of the forces governing the spiral structure. It seems that the neutral hydrogen is primarily a tracer of locations where the overall distribution of stars is producing a gravitational sink. Other spiral tracers, in particular the molecules, are better considered as tracers of regions where the gas has been compressed, perhaps (at least on a large scale) by the shock front predicted by the density-wave theory.

Type
Part 6: Large-Scale Galactic Structure
Information
Symposium - International Astronomical Union , Volume 60: Galactic Radio Astronomy , 1974 , pp. 551 - 572
Copyright
Copyright © Reidel 1974 

References

Bajaja, E. and Colomb, F. R.: 1973, Carnegie Inst. Washington Publ. No. 632.Google Scholar
Barbanis, B. and Woltjer, L.: 1967, Astrophys. J. 150, 461.CrossRefGoogle Scholar
Burke, B. F.: 1957, Astron. J. 62, 90.CrossRefGoogle Scholar
Burton, W. B.: 1971, Astron. Astrophys. 10, 76.Google Scholar
Burton, W. B.: 1972, Astron. Astrophys. 19, 51.Google Scholar
Burton, W. B.: 1973, Publ. Astron. Soc. Pacific 85, 679.CrossRefGoogle Scholar
Burton, W. B. and Bania, T. M.: 1974, Astron. Astrophys, in press.Google Scholar
Burton, W. B. and Shane, W. W.: 1970, in Becker, W. and Contopoulos, (eds.), ‘The Spiral Structure of our Galaxy’, IAU Symp. 38, 397.Google Scholar
Burton, W. B. and Verschuur, G. L.: 1973, Astron. Astrophys. Suppl. 12, 145.Google Scholar
Davies, R. D.: 1972, Monthly Notices Roy. Astron. Soc. 160, 381.CrossRefGoogle Scholar
Davies, R. D. and Cohen, R. J.: 1973, Monthly Notices Roy. Astron. Soc., in preparation.Google Scholar
Dieter, N. H.: 1972, Astron. Astrophys. Suppl. 5, 21.Google Scholar
Fujimoto, M. and Tanahashi, Y.: 1971, Publ. Astron. Soc. Japan 23, 7.Google Scholar
Fujimoto, M. and Tanahashi, Y.: 1971, Publ. Astron. Soc. Japan 23, 13.Google Scholar
Garzoli, S. L.: 1972, Carnegie Inst. Washington Publ. No. 629.Google Scholar
Gum, C. S., Kerr, F. J., and Westerhout, G.: 1960, Monthly Notices Roy. Astron. Soc. 121, 132.CrossRefGoogle Scholar
Habing, H. J.: 1966, Bull. Astron. Inst. Neth. 18, 323.Google Scholar
Harten, R. H.: 1971, Ph.D. Thesis, University of Maryland.Google Scholar
Humphreys, R. M.: 1970, Astron. J. 75, 602.CrossRefGoogle Scholar
Humphreys, R. M.: 1972, Astron. Astrophys. 20, 29.Google Scholar
Kepner, M.: 1970, Astron. Astrophys. 5, 444.Google Scholar
Kerr, F. J.: 1957, Astron. J. 62, 93.CrossRefGoogle Scholar
Kerr, F. J. and Hindman, J. V.: 1970, Australian J. Phys. Astrophys. Suppl. No. 18, 1.Google Scholar
Kerr, F. J., Harten, R. H., and Ball, D. L.: 1974, Astron. Astrophys. Suppl., in press.Google Scholar
Knapp, G. R.: 1972, Astron. Astrophys. 21, 163.Google Scholar
Kwee, K. K., Muller, C. A., and Westerhout, G.: 1954, Bull. Astron. Inst. Neth. 12, 117.Google Scholar
Lin, C. C.: 1971, in de Jager, C. (ed.), Highlights of Astronomy, Vol. 2, Reidel Publ. Co., Dordrecht, p. 377.Google Scholar
Lin, C. C., Yuan, C., and Shu, F. H.: 1969, Astrophys. J. 155, 721.CrossRefGoogle Scholar
Lindblad, P. O.: 1974, Astron. Astrophys. Suppl. 16, 207.Google Scholar
Lynds, B. T.: 1970, in Becker, W. and Contopoulos, G. (eds.), ‘The Spiral Structure of Our Galaxy’, IAU Symp. 38, 26.Google Scholar
Mathewson, D. S., Kruit, P. C. van der, and Brouw, W. N.: 1972, Astron. Astrophys. 17, 468.Google Scholar
Oort, J. H., Kerr, F. J., and Westerhout, G.: 1958, Monthly Notices Roy. Astron. Soc. 118, 379.Google Scholar
Piddington, J. H.: 1973, Monthly Notices Roy. Astron. Soc. 162, 73.CrossRefGoogle Scholar
Roberts, W. W.: 1969, Astrophys. J. 158, 123.CrossRefGoogle Scholar
Schmidt, M.: 1965, Stars and Stellar Systems 5, 513.Google Scholar
Shane, W. W. and Bieger-Smith, G. P.: 1966, Bull. Astron. Inst. Neth. 18, 263.Google Scholar
Simonson, S. C. and Sancisi, R.: 1973, Astron. Astrophys. Suppl. 10, 283.Google Scholar
Tuve, M. A. and Lundsager, S.: 1972, Astron. J. 77, 652.CrossRefGoogle Scholar
Tuve, M. A. and Lundsager, S.: 1973, Carnegie Inst. Washington Publ. No. 630. Google Scholar
Verschuur, G. L.: 1973, Astron. Astrophys. 22, 139.Google Scholar
Weaver, H. and Williams, D. R.: 1973, Astron. Astrophys. Suppl. 8, 1.Google Scholar
Wentzel, D. G.: 1972, Publ. Astron. Soc. Pacific 84, 225.CrossRefGoogle Scholar
Westerhout, G.: 1969, Maryland-Green Bank Galactic 21-cm Line Survey, 2nd ed., University of Maryland, College Park, Maryland.Google Scholar
Westerhout, G.: 1973, Maryland-Green Bank Galactic 21-cm Line Survey, 3rd ed., University of Maryland, College Park, Maryland.Google Scholar
Woerden, H. van: 1967, in van Woerden, H. (ed.), ‘Radio Astronomy and the Galactic System’, IAU Symp. 31.Google Scholar
Yuan, C.: 1969, Astrophys. J. 158, 871.CrossRefGoogle Scholar
Zwicky, F.: 1955, Publ. Astron. Soc. Pacific 67, 232.CrossRefGoogle Scholar