On the Stratification of Elements in the Envelopes Ejected by Type I Supernovae
Abstract
The problem of the chemical composition of the envelopes of type I supernovae (SNI) is investigated. The identification of absorptions in the spectra of different SNI brings us to the conclusion that the abundance of O, C, N and S in these envelopes is noticeably higher than the ‘standard’ stellar abundance. It is expected that the abundance of He is also very high. There are certain reasons for the identification of a Hα absorption in the spectra of SNI, although the abundance of this element in the envelopes cannot be high. The fact that the absorptions of CI and OI in the spectra of SNI appear considerably later than the absorptions of He I, N I and other elements is investigated in detail. This fact is explained on the basis of the assumption that there exists a stratification of elements in the envelopes. The presence of such a stratification is in agreement with the hypothesis that the stars which explode as type I supernovae are relatively massive and sufficiently evolved stars. In agreement with this explanation, the O and C atoms are mainly situated in the inner parts of the envelope, whereas the N and He atoms are situated in its outer parts, and it seems that hydrogen is situated in the most superficial layers (Figure 9). An analysis of the physical conditions inside the envelopes of SNI brings us to the conclusion that the ‘central remnant’ of SNI is a source of anomalously high electromagnetic or corpuscular radiation, which is responsible for the super-excitation of the high atomic levels in the envelopes of SNI.
- Publication:
-
Astrophysics and Space Science
- Pub Date:
- September 1978
- DOI:
- 10.1007/BF00645374
- Bibcode:
- 1978Ap&SS..58...41M
- Keywords:
-
- Stellar Envelopes;
- Stellar Spectra;
- Stellar Structure;
- Supernovae;
- Absorption Spectra;
- Abundance;
- Atomic Energy Levels;
- Chemical Composition;
- H Alpha Line;
- Helium;
- Strata;
- Astrophysics