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HM Sagittae – A most remarkable star

Published online by Cambridge University Press:  12 April 2016

Sun Kwok
Sun Kwok*
Affiliation:
Herzberg Institute of Astrophysics, National Research Council of Canada, Ottawa, Canada KlA 0R6

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HM Sagittae is one of the most unusual objects in the Galaxy for it displays activity in every spectral band from x-ray to radio. Its present variable-star designation was given after the discovery of its optical brightening from 16m to 12m between April and September 1975 (Dokuchaeva and Balazs 1976). It was soon found to have a rich emissionline spectrum similar to that of a planetary nebula (Stover and Sivertsen 1977). Post-brightening monitoring of the object by Ciatti, Mammano and Vittone (1977, 1978) found the B and V magnitudes to be variable with amplitudes of at least one magnitude. Evidence for increasing excitation was found by Ciatti, Mammano and Vittone (1979) with Hell 4686 emerging in October 1978. Wolf-Rayet features of velocities up to 2000 km s-1 have also been seen (Belyakina, Gershberg and Shakhovskaya 1978, 1979; Brown et al. 1978; Ciatti et al. 1978; Wallerstein 1978; Allen 1980; Andrillat and Swings 1982). Analysis of the forbidden line ratios gives an estimated nebula density of 106-107 cm-3 and a gas temperature >104K (Ciatti et al. 1977; Arkhipova and Dokuchaeva 1978; Davidson, Humphreys and Merrill 1979; Arkhipova, Dokuchaeva and Esipov 1979).

Type
Session II – Discussion on Individual Stars
Information
International Astronomical Union Colloquium , Volume 70: The Nature of Symbiotic Stars , 1982 , pp. 209 - 211
Copyright
Copyright © Reidel 1982

References

Allen, D.A., 1980, Mon. Not. Roy Astron. Soc., 190, 75.Google Scholar
Allen, D.A., 1981, paper presented at the North American Workshop on Symbiotic Stars, Boulder.Google Scholar
Andrillat, Y. and Swing, J.P. 1982, this volume.Google Scholar
Arkhipova, V.P. and Dokuchaeva, P.D. 1978, Sov. Astron. Letters, 4(1), 48.Google Scholar
Arkhipova, V.P., Dukuchaeva, P.D. and Esipov, V.F. 1979, Sov. Astron., 23(2), 174.Google Scholar
Belyakina, T.S., Gershberg, R.E. and Shakhovskaya, N.I., 1978, Sov. Astron. Letters, 4(5), 219.Google Scholar
Belyakina, T.S., Gershberg, R.E. and Shakhovskaya, N.I., 1979, Sov. Astron. Letters, 5(6), 349.Google Scholar
Brown, L.W., Feibelman, W.A., Hobbs, R.W., McCracken, C.W. Astrophys. Letters, 19, 75.Google Scholar
Ciatti, F., Mammano, A. and Vittone, A., 1977, Astron. Astrophys., 61, 459.Google Scholar
Ciatti, F., Mammano, A. and Vittone, A., 1978, Astron. Astrophys., 68, 751.Google Scholar
Ciatti, F., Mammano, A. and Vittone, A., 1979, Astron. Astrophys., 79, 247.Google Scholar
Davidson, K., Humphreys, R.M. and Merrill, K.M. 1978, Astrophys. J., 220, 239.Google Scholar
Dokuchaeva, P.D. and Balazs, B. 1976, Astron. Tsink., No. 929, 1.Google Scholar
Feibelman, W.A., Boggess, B., Hobbs, R.W. and McCracken, C.W. 1980, Astrophys. J., 241, 725.Google Scholar
Feldman, P.A. 1977, J. Roy. Astron. Soc. Canada, 71, 386.Google Scholar
Flower, D.R., Nussbaumer, H. and Schild, H. 1979, Astron. Astrophys., 72., LI.Google Scholar
Kwok, S. 1982, this volume.Google Scholar
Kwok, S. and Purton, C.R. 1979, Astrophys. J., 229, 187.Google Scholar
Kwok, S., Bignell, C. and Purton, C.R. 1982, in preparation.Google Scholar
Puetter, R.C., Russell, R.W., Soifer, B.T., Willner, S.P. 1978, Astrophys. J. (Letters), 223, L93.Google Scholar
Slovak, M.H. 1978, Astron. Astrophys., 70, L75.Google Scholar
Stover, R.J. and Sivertsen, S. 1977, Astrophys, J. (Letters), 214, L33.Google Scholar
Taranova, O.G. and Yudin, B.F. 1980, sov. Astorn. Letters, 6(4), 273.Google Scholar
Thronson, H. and Harvey, P.M. 1981, Astrophys. J., in press.Google Scholar
Wallerstein, G. 1978, Publ. Astron. Soc. Pacific, 90, 36.Google Scholar
Willson, L.A. 1981, paper presented at the North American Workshop on Symbiotic Stars, Boulder.Google Scholar