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Intermediate Helium Stars: Atmospheric Parameters, Oblique Rotators and Shells

Published online by Cambridge University Press:  12 April 2016

K. Hunger
K. Hunger*
Affiliation:
Institut für Theoretische PhysikundSternwarte der UniversitatKiel Olshausenstr. 40, 2300 Kiel, F.R.G.

Extract

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Intermediate helium stars are defined by

nHe/nH being the number ratio of He over H. The upper bound which separates the intermediates from the extremes is well-defined (see Sect. 7), whereas the lower bound is rather soft.

The first intermediate helium star discovered was Sigma Ori E (Greenstein and Wallerstein, 1956). Since then, 23 intermediates with V ≤ 1lm have been found (see the list of Walborn, 1983 and also the Annex), mostly through surveys such as that by McConnell et al. (1970) and McConnell (1972). (To this list, the newly discovered object SB 939, Langhans and Heber, 1985, should be added.) It is anticipated that a substantial fraction has as yet escaped detection. The spectral type centres around B2V while nHe/nH is typically of the order of unity.

Type
VI Intermediate Helium Stars
Information
International Astronomical Union Colloquium , Volume 87: Hydrogen Deficient Stars and Related Objects , 1985 , pp. 260 - 276
Copyright
Copyright © Reidel 1986

References

Bolton, C.T.: 1974, Astrophys. J. 192, L7 Google Scholar
Bolton, C.T.: 1983, Harv. Obs. Bull. 7, 241 Google Scholar
Bond, H.E., Levato, H.: 1976, Publ. Astron. Soc. Pac. 88, 905 Google Scholar
Bonsack, W.K., Dyck, H.M.: 1983, Astron. Astrophys. 116, 64 Google Scholar
Borra, E.F., Landstreet, J.D.: 1977, Astrophys. J. 212, 141 CrossRefGoogle Scholar
Borra, E.F., Landstreet, J.D.: 1979, Astrophys. J. 228, 809 CrossRefGoogle Scholar
Carpenter, K.G.: 1985, Astrophys. J. 289, 660 Google Scholar
Caughlan, G.R: 1965, Astrophys. J. 141, 688 Google Scholar
Detz, A.: 1977, Astron. Astrophys. Suppl. 28, 403 Google Scholar
Drake, S.A., Abbot, D.C., Bieging, Z.H., Churchwell, E., Linsky, J.L: 1984, in Radio Stars, ed. Hjellming, R. and Gibson, D., New York: Plenum Google Scholar
Gerlach, M.: 1976, Dissertation, Technische Universität Berlin Google Scholar
Groote, D., Hunger, K.: 1976, Astron. Astrophys. 52, 303 Google Scholar
Groote, D., Hunger, K.: 1977, Astron. Astrophys. 56, 129 Google Scholar
Groote, D., Hunger, K., Schultz, G.V.: 1980, Astron. Astrophys. 83, L5 Google Scholar
Groote, D., Kaufmann, J.P.: 1981, Astron. Astrophys. 94, L23 Google Scholar
Groote, D., Kaufmann, J.P.: 1981, in 23rd Liège Astrophys. Coll, p. 435 Google Scholar
Groote, D., Kaufmann, J.P., Lange, A.: 1982, Astron. Astrophys. Suppl. 50, 77 Google Scholar
Groote, D., Kaufmann, J.P., Theil, U.: 1985, to be publishedGoogle Scholar
Gruschinske, J.: 1982, private communicationGoogle Scholar
Hamann, W.R.: 1981, private communicationGoogle Scholar
Harmanec, P.: 1984, Bull. Astron. Inst. Czechosl. 35, 193 Google Scholar
Havnes, O.: 1981, in 23rd Liège Astrophys. Coll., p. 403 Google Scholar
Havnes, O., Goertz, C.K.: 1984, Astron. Astrophys. 138, 421 Google Scholar
Heintz, W.D.: 1974, Astrophys. J. 79, 397 Google Scholar
Heber, U., Hunger, K.: 1981, Astron. Astrophys. 101, 269 Google Scholar
Hensler, G.: 1979, Astron. Astrophys. 74, 284 Google Scholar
Hesser, J.E., Ugarte, P.: 1976, IAU, Circ. No. 2911 Google Scholar
Hesser, J.E., Walborn, N.R., Ugarte, P.: 1976, Nature 262, 116 CrossRefGoogle Scholar
Hesser, J.E., Moreno, H., Ugarte, P.: 1977, Astrophys. J. 216, L31 Google Scholar
Hunger, K.: 1975, in Problems in Stellar Atmospheres and Envelopes, eds. Baschek, B., Kegel, W.H., Traving, G., Springer, New York, Heidelberg, Berlin, p. 57 CrossRefGoogle Scholar
Hunger, K.: 1986, unpublishedGoogle Scholar
Hunger, K.: 1986, in IAU Coll. No. 90.Google Scholar
Jordan, S.: 1985, private communicationGoogle Scholar
Kaufmann, J.P., Hunger, K.: 1975, Astron. Astrophys. 38, 351 Google Scholar
Kemp, J.C., Herman, L.C.: 1977, Astrophys. J. 218, 770 CrossRefGoogle Scholar
Kurucz, R.L.: 1979, Astrophys. J. Suppl. 40, 1 CrossRefGoogle Scholar
Landstreet, J.D., Borra, E.F: 1978, Astrophys. J. 224, L5 Google Scholar
Langhans, G., Heber, U.: 1985, to be publishedGoogle Scholar
Lee, P., O’Brien, A.O.: 1977, Astron. Astrophys. 60, 259 Google Scholar
Lester, J.B.: 1976, Astrophys. J. 210, 153 Google Scholar
Lester, J.B.: 1979, Astrophys. J. 233, 644 Google Scholar
Levato, H., Malaroda, S.: 1979, Publ. Astron. Soc. Pac. 91, 789 Google Scholar
McConnell, D.J.: 1972, Publ. Astron. Soc. Pac. 84, 388 CrossRefGoogle Scholar
McConnell, D.J., Frye, R.L., Bidelman, W.P.: 1970, Publ. Astron. Soc. Pac. 83, 730 CrossRefGoogle Scholar
Madej, J.: 1981, in 23rd Liège Astrophys. Coll., p. 379 Google Scholar
Mihalas, D.: 1973, Astrophys. J. 184, 851 Google Scholar
Nerney, S.: 1980, Astrophys. J. 242, 723 Google Scholar
Nakajima, R.: 1985, Astrophys. Space Sci. 116, 285 Google Scholar
Odeli, A.: 1974, Astrophys. J. 194, 645 Google Scholar
Odell, A.P., Lebofsky, M.: 1984, Astron. Astrophys. 140, 468 Google Scholar
Osmer, P.S., Peterson, D.M.: Astrophys. J. 187, 117 Google Scholar
Pedersen, H.: 1979, Astron. Astrophys. J. Suppl. 35, 313 Google Scholar
Pedersen, H., Thompson, B.: 1977, Astron. Astrophys. J. Suppl. 30, 11 Google Scholar
Remie, H., Lamers, H.J.G.L.M.: 1982, Astron. Astrophys. 105, 85 Google Scholar
Röser, M.: 1975, Astron. Astrophys. 45, 335 Google Scholar
Shore, S.N.: 1977, Bull. Americ. Astron. Soc. 9, 307 Google Scholar
Shore, S.N., Adelman, S.: 1981, in 23rd Liège Astrophys. Coll., p. 429 Google Scholar
Stoeckly, T.R., Mihalas, D.: 1973, NCAR-TN/STR-84, 1 Google Scholar
Thompson, I.B., Landstreet, J.D.: 1985, Astrophys. J. 289, L9 Google Scholar
Vauclair, S.: 1975, Astrophys. J. 45, 233 Google Scholar
Walborn, N.R.: 1974, Astrophys. J. 191, L95 Google Scholar
Walborn, N.R.: 1975, Publ. Astron. Soc. Pac. 87, 613 Google Scholar
Walborn, N.R.: 1982, Publ. Astron. Soc. Pac. 94, 322 CrossRefGoogle Scholar
Walborn, N.R.: 1983, Astrophys. J. 268, 195 Google Scholar
Walborn, N.R.:, Hesser, J.E.: 1976, Astrophys. J. 205, L87 Google Scholar
Walker, H.: 1985, Astron. Astrophys. 152, 58 Google Scholar