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Observations of interstellar Lyman-α with the Orbiting Astronomical Observatory

Published online by Cambridge University Press:  14 August 2015

B. D. Savage  and
A. D. Code
B. D. Savage
Affiliation:
Space Astronomy Laboratory, Washburn Observatory, University of Wisconsin, Madison, Wis., U.S.A.
A. D. Code
Affiliation:
Space Astronomy Laboratory, Washburn Observatory, University of Wisconsin, Madison, Wis., U.S.A.

Abstract

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The equivalent width of the blended line at Lyman α is given for 48 stars measured with the OAO-A2 scanning spectrometer. This provides an upper limit to the neutral hydrogen column density. In the Orion association these upper limits are significantly lower than the column densities determined from 21-cm emission line measurements. The determination of the Lyman α equivalent width for θ Ori by Carruthers is rediscussed and agreement between 21-cm absorption measures and Lyman α absorption is obtained for a spin temperature in the range of 40–70 K. It is suggested that the most likely explanation for the discrepancies found for the other Orion stars is that the 21-cm emission primarily occurs beyond the Belt stars.

The correlation between the OAO blended equivalent widths and color excess, 4430 Å absorption, and interstellar sodium absorption are examined. Excellent correlation between sodium and hydrogen column densities is found.

Type
Part III: Interstellar Absorption and Emission
Information
Symposium - International Astronomical Union , Volume 36: Ultraviolet Stellar Spectra and Related Ground-Based Observations , 1970 , pp. 302 - 314
Copyright
Copyright © Reidel 1970 

References

Carruthers, G.: 1968, Astrophys. J. 151, 269.CrossRefGoogle Scholar
Carruthers, G.: 1969, Astrophys. J. 156, L97.CrossRefGoogle Scholar
Clark, B. G.: 1965, Astrophys. J. 142, 1398.CrossRefGoogle Scholar
Code, A. D. and Bless, R. C.: 1969, this volume, p. 173–177.CrossRefGoogle Scholar
Duke, D.: 1951, Astrophys. J. 113, 100.CrossRefGoogle Scholar
Goldstein, S. J. and MacDonald, D.: 1969, Astrophys. J., in press.Google Scholar
Habing, H. J.: 1968, Bull. Astron. Inst. Netherl. 20, 120.Google Scholar
Herbig, G. H.: 1968, Z. Astrophys. 68, 243.Google Scholar
Howard, W. E., Wentzel, D. G., and McGee, R. X.: 1963, Astrophys. J. 138, 988.CrossRefGoogle Scholar
Jenkins, E. B. and Morton, D. C.: 1967, Nature 215, 1257.CrossRefGoogle Scholar
Jenkins, E. B., Morton, D. C., and Matilsky, T. A.: 1969, in press.Google Scholar
Menon, T. K.: 1959, Astrophys. J. 127, 28.CrossRefGoogle Scholar
Merrill, P. W., Sanford, R. F., Wilson, O. C., and Burwell, C. G.: 1937, Astrophys. J. 86, 274.CrossRefGoogle Scholar
Morton, D. C.: 1967, Astrophys. J. 147, 1017.CrossRefGoogle Scholar
Muller, C. A.: 1959, Proc. IAU Symp. 9, Stanford Univ. Press, Stanford, Calif., p. 360.Google Scholar
Stoeckly, R. and Dressler, K.: 1964, Astrophys. J. 139, 240.CrossRefGoogle Scholar
Takakubo, K. and Van Woerden, H.: 1966, Bull. Astron. Inst. Netherl. 18, 488.Google Scholar
Wampler, E. J.: 1966, Astrophys. J. 144, 921.CrossRefGoogle Scholar