F. Musaev
A time series of high-resolution spectra was observed in the optical wavelength region for the bright proto-planetary nebula IRAS22272+5435 (HD235858), along with a simultaneous monitoring of its radial velocity and $BVR_C$ magnitudes. The…
Radial velocity measurements, $BVR_C$ photometry, and high-resolution spectroscopy in the wavelength region from blue to near infrared are employed in order to clarify the evolutionary status of the carbon-enhanced metal-poor star HD112869…
Two observational campaigns were carried out during the eclipses of EE Cep in 2003 and 2008/9 to verify whether the eclipsing body in the system is indeed a dark disk and to understand the observed changes in the depth and durations of the…
We present chemical abundances in the photosphere of $\delta$ Scuti -- the prototype of the class of pulsating variables -- determined from the analysis of a spectrum obtained at Terskol observatory 2 meter telescope with resolution…
We present an overview of the spectral variability of the peculiar F-type hypergiant Rho Cas, obtained from our long-term monitoring campaigns over the past 8.5 years with four spectrographs in the northern hemisphere. Between 2000 June and…
We report spectral time series of the late O-type runaway supergiant HD 188209. Radial velocity variations of photospheric absorption lines with a possible quasi-period ~ 6.4 days have been detected in high-resolution echelle spectra.…
A careful investigation of a CCD spectrum of the SB1 system kappa Cnc in the spectral region 3800 A - 8000 A resulted in the discovery of the lines of the secondary star. We then analyzed several short-wavelength range Reticon spectra…
We discuss the way of increasing of the number of chemical elements, investigated in stellar spectra. We can reach it by using spectrum synthesis method, new atomic data and observation of stellar spectra with resolution comparable to solar…
Between 2000 June and September an exceptional variability phase occurred in the peculiar F-type hypergiant Rho Cas, when the V-brightness dimmed by at least a full magnitude. The star recovered from this deep minimum by 2001 April. It is…