Abstract. We present in this paper several high resolution (R = 27 000) spectra of five UXORs (UX Ori, CQ Tau, BF Ori, RR Tau, WW Vul), which cover the entire visual range, from 3900 to about 8700Å. There are between 4 and 7 spectra per star, obtained over a time interval of two years. Simultaneous or quasi-simultaneous photometric observations were also obtained at the Crimean Astrophysical Observatory. The complete, reduced and normalized spectra are available in electronic form. We show for each star a selection of the most interesting lines, and the full spectrum of UX Ori computed by averaging the spectra obtained when the star was at maximum light. For UX Ori we show also the synthetic spectrum and provide an identification of most of the lines. The spectra are too sparse to form true time sequences; however, they provide an extremely useful database for studies of UX Ori-type stars. We discuss briefly the main features of the spectra. We show that they contain many time-stable photospheric lines that can be described to a good approximation by the synthetic spectra of normal A stars with log g = 3.5−4 and we derive for each star effective temperature, gravity and rotational velocity. We examine the time variability of selected lines and study their connection with the photometric activity of the stars. Two different types of spectral variability are identified. One is common to all stars with circumstellar (CS) gas and is caused by perturbations of the physical and kinematic conditions of the emitting region. There is no correlation between this type of activity and the brightness variations of the star. On the contrary, a second type of spectral variability correlates well with the brightness variations and is very likely connected with the screening effect of an opaque dust cloud which sporadically intersects the line of sight. This type of variability has been observed in its simplest form in one of the RR Tau spectra, where the equivalent width of the forbidden line [O i] 6364Å increased by a factor of about three as the star faded by approximately the same amount.

Aims. We investigate the spectroscopic behaviour of the young B0e star HD 53367 within a cooperative observing programme conducted from 1994 to 2005. Methods. The data include more than 100 high-resolution spectra collected at the Crimean Astronomical Observatory (CrAO) near Results. We confirm that the long-term photometric variability of HD 53367 is related to the alternation of two states of this object when the gaseous circumstellar envelope disappears and rises again. Both these processes start near the star and spread to the outlying parts of the envelope. We find that the radial velocities of He i and O ii photospheric lines demonstrate a cyclic variability with a period of P = 183.7 days and semi-amplitude K = 19 km s −1 . The radial velocity change is interpreted in the framework of a model in which the star is a component of an eccentric binary system. An orbital solution is derived and the system's parameters estimated. We find that the orbital eccentricity is e = 0.28, and the mean companion separation is 1.7 AU. Conclusions. Based on the estimated parameters, we conclude that the system consists of a massive (∼20 M ) main sequence primary B0e star, and a secondary which is most likely a 5 solar mass pre-main sequence object. We found evidence that the main part of the circumstellar gas in this system is concentrated near the secondary companion. Although the young age of HD 53367, its evolved primary B0e star seems to have already became a classical Be star exhibiting a specific alternation of the B-Be stages.

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