SIMBAD references

The interacting binary star AX Mon (K0 III + B3 V) has been observed at the Tartu Observatory, Estonia, from 1985 to 1997 using the 1.5 meter telescope. 75 spectrograms are analyzed in the present paper. The hydrogen Balmer lines, Hα and Hβ, occasionally also Hγ and Hδ exhibit P Cygni like profiles. Variations in the intensities, equivalent widths, radial velocities and full widths at half maximum of the emission and absorption components of the Balmer lines on timescales from days to about 10-12 years have been found. The variations are caused mostly by variability in the extent and physical characteristics of the B star envelope. Weak orbital variations (P = 232.5 days) of Hβ and Hγ show that these lines form closer to the B star than Hα. Emission lines of Fe II probably arise in the envelope of the hot star as well as in the stream of matter between the K giant and the B star.