Structure of envelopes ejected by Novae

The paper contains an analysis of the structure of envelopes ejected during the outbursts of Novae. The data used for this purpose: (a) Direct photographs of envelopes and the photographs taken with the use of different colour filters; (b) Spectra of envelopes. The envelope of DQ Her is studied most carefully. The analysis of all available data for the envelopes around DQ Her and V 603 Aql permits us to outline a morphological model of these envelopes, see Figure 3. It appears, that the structure of both these envelopes is approximately identical and that the difference in the observed properties of the photographic images of the nebulae (Figure 2 and Figure 4) is connected with a difference in the orientation of the polar axes of the envelopes relative to the line of sight. The envelope ejected during the outburst of T Aur (Figure 5) reveals the same properties, which are characteristic for the envelopes of DQ Her and V 603 Aql.From this we conclude that the distribution of gases inside the envelopes of the majority of Novae is approximately of the same character. This speaks in favour of the presence of certain forces around many Novae, which guide the motion of ejected plasma along some quite definite directions inside rather small solid angles. It seems that the only conceivable forces of this type may be the forces of a magnetic nature. This hypothesis for example permits us to explain the difference between the envelope of GK Per (Figure 1) and the envelopes of DQ Her, V 603 Aql, T Aur (Figures 2, 4 and 5).Comparing the velocity of expansion of the envelope of DQ Her and the rate of change of its angular size we computed that the distance to DQ Her is equal to 320 pc.On the base of photographs of the envelope of DQ Her it is found that in 1968 the fluxF _H of radiation in the H-line was equal to (6±2)×10^–12 ergs/cm²sec, whereas the mass of the envelope was equal to 10²⁹ G and its electronic concentrationn _e to 2×10³ cm^–3. Several hypotheses, which may explain the stratification of emission from different elements inside the envelope are discussed.