Abstract
Two models of the origin of the spectrum of type I supernovae are analysed: (I) the photosphere of the ‘central remnant’ and the expanding shell are separated by a density cavity; (II) the ‘photosphere’ (the layer which produces the continuous spectrum) is the inner part of the expanding shell. The arguments are given in favour of model I.
Opacity of the shell close to light maximum for λ>4000 Å is mostly due to Thomson scattering; soon after light maximum (and it may be already at light maximum) the shell becomes completely transparent in this region of the spectrum. The problem of the origin of the very large width and of the relatively high central residual intensities of the absorption lines in the spectra of type I supernovae are analysed. A very noticeable dispersion in the velocities of the radial gas motions in the shell is the principal cause of the large equivalent width of the absorption lines in the spectra of these supernovae. The role played by the inhomogeneities in the shell is also discussed. The depth of the strong absorption lines produced by a very inhomogeneous shell may be equal to the filling factor of the medium.
From the analysis of the spectra of supernova 1972e a lower limit for the mass of the shell is obtained (M>1031 g). Then from the fact of absence of a detectable H-absorption line and a simultaneous presence of strong Siii absorption lines (6347, 6371 Å) in the spectrum of supernova 1972e it follows that the ratio Si/H is at least two or three orders greater than that for the ‘normal’ stars.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Allen, C. W.: 1963,Astrophysical Quantities, Athlone Press, London, 2nd ed.
Baschek, B., Carz, T., Holweger, H., and Richter, J.: 1970,Astron. Astrophys. 4, 229.
Van den Bergh, S., Marschner, A. P., and Terzian, Y.: 1973,Astrophys. J. Suppl., No. 227.
Branch, D. and Greenstein, J. L.: 1971,Astrophys. J. 167, 89.
Branch, D. and Patchett, B.: 1973,Monthly Notices Roy. Astron. Soc. 161, 71.
Colgate, S. A. and McKee, Ch.: 1969,Astrophys. J. 157, 623.
Falk, S. W. and Arnett, W. D.: 1973,Astrophys. J. Letters 180, 65.
Grasberg, E. K., Imshennik, V. S., and Nadyozhin, D. K.: 1971,Astrophys. Space Sci. 10, 3.
Goss, W. M., Schwarz, U. J., and Wesselius, P. R.: 1973,Astron. Astrophys. 28, 305.
Gull, S. F.: 1973,Monthly Notices Roy. Astron. Soc. 162, 135.
Holm, A. V., Wu, C. C., and Caldwell, J. J.: 1973,Bull. Am. Astron. Soc. 5, 28.
Kendall, M. G. and Moran, P. A. P.: 1963, ‘Geometrical Probability’,Griffin's Statistical Monographs and Courses, No. 5C, Griffin, London.
Kirshner, R. P., Willner, S. P., Becklin, E. E., Neugebauer, G., and Oke, J. B.: 1973a,Astrophys. J. Letters 180, 97.
Kirshner, R. P., Oke, J. B., Penston, M., and Searle, L.: 1973b,Astrophys. J. 185, 303.
Kopylov, I. M.: 1953,Izv. Krymsk. Astrophys. Obs. 10, 200.
McLaughlin, D. B.: 1960,Stars and Stellar Systems 6, 585.
Mustel, E. R.: 1971a,Astron. Zh. 48, 3.
Mustel, E. R.: 1971b,Astron. Circ. No. 649.
Mustel, E. R.: 1971c,Astron. Zh. 48, 665.
Mustel, E. R.: 1973,Astron. Zh. 50, 1121.
Mustel, E. R. and Baranova, L. I.: 1965,Astron. Zh. 42, 42.
Pikel'ner, S. B.: 1966,Foundations of Cosmic Electrodynamics, Moscow, 2nd ed. (in Russian).
Pskovskii, Yu. P.: 1968,Astron. Zh. 45, 945.
Pskovskii, Yu. P.: 1970,Astron. Zh. 47, 994.
Sobolev, V. V.: 1947,Moving Stellar Envelopes, Leningrad (in Russian).
Travis, L. D. and Matsushima, S.: 1968,Astrophys. J. 154, 689.
Williams, D. R. W.: 1973,Astron. Astrophys. 28, 309.
Wilson, O. C.: 1934,Astrophys. J. 80, 259.
Woltjer, L.: 1972,Ann. Rev. Astron. Astrophys. 10, 129.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Mustel, E.R., Chugay, N.N. The physical conditions in the shells of type I supernovae. Astrophys Space Sci 32, 39–53 (1975). https://doi.org/10.1007/BF00646216
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00646216