SIMBAD references

T. Iijima, Astronomical Observatory of Padova, Asiago Station, reports that, following the announcements of a brightening of the symbiotic star BF Cyg via AAVSO and VSNET alerts, a high dispersion spectrogram (range 435-612 nm; resolution 10000) was taken on Apr. 20.146 UT with an echelle spectrograph mounted on the 182-cm telescope at the Mount Ekar station of the Astronomical Observatory of Padova. Spectra in the last observational season (Nov. 2007) showed numerous emission lines of H I, He I, Fe II, [Fe II], [N II], Na I, etc. In contrast to them, the emission lines of He I, [Fe II], and [N II] have disappeared in the new spectrum, and the other lines have fairly weakened. P-Cyg-type absorption components, blue-shifted by about -40 km/s, have developed for Fe II and Na I lines. These spectral features confirm that BF Cyg has entered a new explosive stage.