Astron. Astrophys. 353, 952-957 (2000)

8. Conclusions

With this paper FG Ser enters the list of symbiotic objects with known orbital parameters. It turns out that at least as far as the orbital characteristics are concerned, FG Ser is an absolutely "average" symbiotic: The period is typical for s-type objects, there is at most very little eccentricity, and the system is well detached. With the masses of   for the cool star and   for the white dwarf FG Ser fits well into the Table of stellar masses determined for symbiotic binaries so far (Table 4). It appears that most symbiotic systems have comparable masses, with a mass ratio of the order .

Table 4. Masses of the stellar components in symbiotic binary systems.

The average mass of the hot component in the symbiotic systems of Table 4 is   which is below the canonical value for single white dwarfs. For binaries with periods of a few hundred days, Li & van den Heuvel (1997) argue that for the white dwarf to become a Ia supernova, an initial minimum mass   is required. According to this scenario, the symbiotics in Table 4 are thus unlikely to suffer a SN event.

© European Southern Observatory (ESO) 2000

Online publication: January 18, 2000
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