2006CBET..633....1I

T. Iijima, Astronomical Observatory of Padova, Asiago, reports that, in the course of the monitoring of spectral variations of symbiotic stars, high-dispersion spectra (range 427-596 nm) of BF Cyg were taken on Aug. 30.9 and 31.9 UT with an echelle spectrograph mounted on the 1.82-m telescope at Mount Ekar. The present outburst of this object started at the end of July 2006 (CBET 596). The last spectrum in quiescence was taken on Apr. 8.1 with the same instruments. Comparing with the spectrum in the variable's quiet stage, the emission lines of Fe II, Cr II, and Ti II have significantly strengthened, while the intensity of the nebular line [O III] 500.7-nm decreased from 72 on Apr. 8.1 to 6 on Aug. 30.9, where the intensity of H_beta is taken to be 100. The emission line of [O III] 436.3-nm has nearly disappeared in the recent spectra. P-Cyg-type absorption components have appeared on the lines of H I, He I, Fe II mult. 42, and Na I D1 and D2. The blueshifts of the absorption components were found to range from -57 km/s for Fe II 516.9-nm to -145 km/s for He I 587.6-nm, and that of H_beta was about -70 km/s. Some spectral changes were noticed also between Aug. 30.9 and 31.9: The intensity of the emission line of He II 468.6-nm relative to H_beta (= 100) was about 4 on Aug. 30.9, which was still < 7 on Apr. 8.1. This emission line, however, strengthened during only one day, and its intensity had risen to 18 on Aug. 31.9; the absorption components of the lines of Fe II mult. 42 disappeared at the same time, those of the other lines being nearly the same. Some significant changes seem to have occurred in this object at that time.