7 Emission line spectrum

The emission line spectrum is produced in the shell and because of the presence of C II, Mg I and Ca II it corresponds probably to an early A type star. This would correspond to a temperature of about 9 000 K, which can be compared to the 9 000 derived photometrically by Bergner et al. (1990). Observe also that no He II lines are observed, which are the habitual signature of an X-ray source.