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Spectroscopic observations of the δ Scorpii binary during its recent periastron passage
The bright star Delta Sco has been considered a typical B0-type object for many years. Spectra of the star published prior to 1990 showed no evidence of emission, but only of short-term line profile
High-Resolution Spectroscopy of the Yellow Hypergiant ρ Cassiopeiae from 1993 through the Outburst of 2000-2001
We present an overview of the spectral variability of the peculiar F-type hypergiant ρ Cas, obtained from our long-term monitoring campaigns over the past 8.5 yr with four spectrographs in the
Spectroscopic study of the long-period dust-producing WC7pd+O9 binary HD 192641
We present the results of an optical spectroscopic study of the massive Wolf-Rayet binary HD192641=WR137. These 1986-2000 data cover the dust-formation maximum in 1997. Combining all available
A search for the cause of cyclical wind variability in O stars. Simultaneous UV and optical observations including magnetic field measurements of the O7.5III star xi Persei
We present the results of an extensive observing campaign on the O7.5 III star Persei. The UV obser- vations were obtained with the International Ultraviolet Explorer. Per was monitored continuously
HIGH-RESOLUTION OPTICAL SPECTRA OF THE HEAD OF THE COMET C/1996 B2 (HYAKUTAKE)
On 23 and 27 March 1996, we obtained high-resolution (R 26,000) echelle spectra by manually guiding on the head of Comet C/1996 B2 (Hyakutake). The two spectra cover different but slightly
A new phase of activity of the Herbig Be star HD 200775 in 2001: Evidence for binarity
The results of high-resolution spectroscopy of the Herbig Be star HD 200775 obtained within the framework of a cooperative observing programme in 2000–2002 are presented. A new high-activity phase of
Spectroscopy of the growing circumstellar disk in the Delta Scorpii Be binary
We present the results of a spectroscopic monitoring program of the binary system Delta Scorpii, whose primary became a Be star after the last periastron encounter in the Summer of 2000. The
Spectroscopic and Spectropolarimetric Observations of V838 Monocerotis
The spectroscopic and spectropolarimetric variability of the peculiar variable V838 Monocerotis during the brighter phases of its multiple outbursts in 2002 is presented. Significant line profile
A SEARCH FOR AP STARS WITH VERY LONG PERIODS
Four-color (uvby) photoelectric observations have yielded new periods for three peculiar A-type stars. For HD 8441, the period P is equal to 69.5 days, for RD 12288, P = 34.9 days, and for RD 216533,
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