This is a theoretical study of changes in several characteristics of the spectra of early-type supergiants owing to scattering of continuum radiation. Thomson scattering on free electrons is treated as the scattering mechanism, although the approach used here is quite general. The reason for changes in the spectral class of a star with constant bolometric luminosity and surface temperature is elucidated and the necessary conditions for their realization are introduced. The effect of scattering in the continuum on the magnitude of the intensity jumps in the hydrogen spectrum depending on the degree of ionization is studied. The conditions under which the Schuster mechanism for formation of emission lines sets in are clarified both for an isothermal atmosphere and for an atmosphere with a temperature gradient.
Similar content being viewed by others
References
R. M. Humphreys and K. Davidson, Astrophys. J. 232, 409 (1979).
S. P. Owocki, K. G. Gayley, and N. V. Shaviv, Astrophys. J. 616, 525 (2004).
S. C. Wolff, The A-type Stars. Problems and Perspectives, NASA SP-46 (1983).
A. Schuster, Astrophys. J. 21, 1 (1905).
V. A. Ambartsumyan, Trudy AO LGU 23, 6 (1938).
D. G. Hummer and G. Rybicki, Methods in Computational Physics, N. Y., Acad. Press (1967).
K. B. Gebbie and R. N. Thomas, Astrophys. J. 154, 285 (1968).
J. P. Harrington, Astrophys. J. 162, 913 (1970).
G. L. Israelian and A. G. Nikoghossian, J. Quant. Spectrosc. Radiat. Transfer 56, 509 (1996).
V. A. Ambartsumyan, DAN SSSR 38, 257 (1943).
V. A. Ambartsumyan, Scientific Papers, vol. 1, Izd. AN ArmSSR (1960).
A. G. Nikoghossian and H. A. Haruthyunian, Astrophys. Sp. Sci. 64, 269 (1978).
G. A. Arutyunyan and A. G. Nikogosyan, DAN SSSR 242, 66 (1978).
A. G. Nikoghossian and G. L. Israelian, J. Quant. Spectrosc. Radiat. Transfer 56, 501 (1996).
D. Mihalas, Stellar Atmospheres, San-Francisco, Freeman (1978).
V. V. Sobolev, A Course in Theoretical Astrophysics, Nauka, Moscow (1985).
S. Chandrasekhar, ZS f. Astrophys. 8, 167 (1934).
À. Unsold, ZS f. Astrophys. 8, Heft 1 (1934).
V. V. Sobolev, Radiative Transfer in the Atmospheres of Stars and Planets, Gostekhizdat, Moscow (1956).
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Astrofizika, Vol. 63, No. 4, pp. 611-629 (November 2020)
Rights and permissions
About this article
Cite this article
Nikoghossian, A.G. Some Manifestations of Nonstationarity in the Spectra of Early-Type Supergiants. Astrophysics 63, 534–551 (2020). https://doi.org/10.1007/s10511-020-09657-w
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10511-020-09657-w