相关论文: Very peculiar wind from BD+53 2790, the optical co…

We report the detection of a strong, organised magnetic field in the O9IV star HD 57682, using spectropolarimetric observations obtained with ESPaDOnS at the 3.6-m Canada-France-Hawaii Telescope within the context of the Magnetism in…

The atmosphere of the extremely high-velocity (530-920 km/s) early B-type star HD271791 is enriched in $\alpha$-process elements, which suggests that this star is a former secondary component of a massive tight binary system and that its…

We present the results of optical wavelength observations of the unusual SMC eclipsing binary system HD 5980 obtained in 1999 and 2004--2005. Radial velocity curves for the erupting LBV/WR object (star A) and its close WR-like companion…

\mu\ Columbae is a prototypical weak-wind O-star for which we have obtained a high-resolution X-ray spectrum with the Chandra LETG/ACIS-S instrument and a low resolution spectrum with Suzaku. This allows us, for the first time, to…

We present BeppoSAX observations of the peculiar long period polar system V1309 Ori (RXJ0515.6+0105). The source was detected simultaneously at soft and, for the first time, at hard X-rays with the LECS and the MECS detectors. Both, the…

We present high-dispersion echelle spectroscopic observations and a narrow-band [N II] image of the remarkable jet-like features of He 2-90. They are detected in the echelle spectra in the H-alpha and [N II] lines but not in other nebular…

The extraordinary magnetic Ap star HD75049 has been studied with data obtained with the ESO VLT and 2.2-m telescopes. Direct measurements reveal that the magnetic field modulus at maximum reaches 30kG. The star shows photometric, spectral…

PSR B1259-63 is a gamma-ray binary system with a 48 ms radio pulsar orbiting around an O9.5Ve star, LS 2883, in a highly eccentric ~3.4 yr long orbit. Close to the periastron the system is detected from radio up to the TeV energies due to…

By analogy with the solar system, it is believed that stellar winds will form bow shocks around exoplanets. For hot Jupiters the bow shock will not form directly between the planet and the star, causing an asymmetric distribution of mass…

For the first time, we obtained the high-resolution (R=15000 and 60000) optical spectra for the extremely luminous star No.12, associated with the IR-source IRAS20308+4104, a member of the CygOB2 association. We have found about 200…

The rapid rotation of Be stars may be caused in some cases by past mass and angular momentum accretion in an interacting binary in which the mass donor is currently viewed as a small, hot subdwarf stripped of its outer envelope. Here we…

New spectroscopic observations (R=15000 and 40000) are given for 31 nearby (V < 11) BHB star candidates. IUE low-resolution spectra are available for most of them. New determinations of temperature, gravity, reddening and abundances were…

Analysing a large body of observational data, we found that HD 135160 is a quadruple 2+2 system, composed of a massive ellipsoidal binary ('heartbeat' star) with components Aa and Ab in an eccentric 8.234 d orbit and an eclipsing binary…

An extensive beryllium abundance analysis was conducted for 118 solar analogs (along with 87 FGK standard stars) by applying the spectrum synthesis technique to the near-UV region comprising the Be II line at 3131.066 A, in an attempt to…

Observations of the WC9+OB system WR 65 in the infrared show variations of its dust emission consistent with a period near 4.8~yr, suggesting formation in a colliding-wind binary (CWB) having an elliptical orbit. If we adopt the IR maximum…

The optical spectra of the B-supergiant LS III+52 24 (IRAS 22023+5249) obtained at the 6-meter telescope BTA with a resolution R$\ge$60000 in 2010-2021 revealed signs of wind variability and velocity stratification in the extended…

We carried out low resolution spectroscopic observations in the wavelength range 3400-4700 A of 20 He-weak and 8 He-strong stars to determine their fundamental parameters by means of the Divan-Chalonge-Barbier (BCD) spectrophotometric…

IC\,4997 is a planetary nebula well known by its variability. We present high-resolution spectra of IC\,4997 obtained in 1993, 2019, and 2020 that reveal changes in the H$\alpha$ and [N\,{\sc ii}] emission line profiles, which had never…

The spectra of stars with the B[e] phenomenon are dominated by features that are related to physical conditions of circumstellar material around these objects and are not intrinsic to the stars. Previous studies have shown that emission…

We present eleven years of high-resolution, spectroscopic observations for the star EM~Cep. EM~Cep switches between B and Be star states, as revealed by the level of H$\alpha$ emission, but spends most of its time in the B~star state.…