相关论文: Spectral atlas of A-type supergiants

The results of our second stage (1998-2018) of the detailed spectroscopy of peculiar supergiants identified with galactic infrared sources, performed mainly at the 6-meter BTA telescope are summarized. The main aspect of the program is a…

We aim to combine asteroseismology, spectroscopy, and evolutionary models to establish a comprehensive picture of the evolution of Galactic blue supergiant stars (BSG). To start such an investigation, we selected three BSG candidates for…

Blue supergiants of spectral types B and A are the visually brightest stars in spiral and irregular galaxies, with their most luminous members (at M_V=-10) outshining entire dwarf galaxies. This characteristic allows us to use them as…

Over the past two decades the echelle spectrograph NES of the 6-m telescope was used to perform high resolution spectroscopy of far evolved stars spanning a wide range of initial masses. The studies cover a diversity of stars with high…

Blue supergiant stars of B and A spectral types are amongst the visually brightest non-transient astronomical objects. Their intrinsic brightness makes it possible to obtain high quality optical spectra of these objects in distant galaxies,…

An atlas of spectra of the unique high luminosity objects MWC 314 and IRC+10420 taken with the CCD echelle spectrograph (R=15000) at the prime focus of the 6-m telescope of SAO is presented. About 320 emission and absorption features of…

We present an Echelle+CCD, high S/N, high resolution (R = 20\,000) spectroscopic atlas of 108 well-known objects representative of the most common types of peculiar and variable stars. The wavelength interval extends from 4600 to 9400 Ang,…

We report the results of a long-term spectroscopic monitoring of the A-type supergiant with the B[e] phenomenon 3 Pup = HD 62623. We confirm earlier findings that it is a binary system. The orbital parameters were derived using…

We present a digital atlas of peculiar, high-luminosity massive stars in the near-infrared region (10470-11000 A) at medium resolution (R~7000). The spectra are centered around He I 10830 A, which is formed in the wind of those stars, and…

Observational manifestations of far evolved stars at the asymptotic giants branch and their nearest descendants are briefly considered. Main results of their chemical composition determinations based on long term high resolution…

We present an atlas composed of more than 1500 spectra of late-type stars (spectral types from G to M) observed simultaneously in the optical and calcium triplet spectral ranges. These spectra were obtained as part of a survey to search for…

The atlas of the spectrum of the B[e] star CI Cam obtained with the 6-meter BTA telescope in combination with the NES spectrograph in the wavelength interval of 395$\div$780 nm with a resolution of $\lambda/\Delta\lambda\ge60\,000$ is…

Optical spectra of the peculiar supergiant 3Pup taken in 1997-2008 are used to analyze the spectral peculiarities and velocity field in its atmosphere. The profiles of strong FeII lines and of the lines of other iron-group ions have a…

Aims: We study the optical spectral properties of a sample of stars showing far infrared colours similar to those of well-known planetary nebulae. The large majority of them were unidentified sources or poorly known in the literature at the…

Massive BA-type supergiants are among the visually brightest stars in galaxies with active star formation. As such they are versatile tools for studies of stellar and galactochemical evolution. Moreover, they can act as distance indicators…

The phenomenon of spectral mimicry refers to the fact that hypergiants and post-AGB supergiants - stars of different masses in fundamentally different stages of their evolution have similar optical spectra, and also share certain other…

Known bright S stars, recognized as such by their enhanced s-process abundances and C/O ratio, are typically members of the asymptotic giant branch (AGB) or the red giant branch (RGB). Few modern digital spectra for these objects have been…

The observations and comprehensive study of intermediate initial mass stars at the late stages of evolution, and after the asymptotic giant branch (AGB) in particular, are of crucial importance to identify the common properties for the…

Aiming to explore weak spectral features of stellar and interstellar origin we used the NES echelle spectrograph of the 6-m telescope to obtain high-resolution spectra for 13 hot O3 - B4 stars in the Cyg OB2 association, including a high…

The searches for transiting exoplanets have produced a vast amount of time-resolved photometric data of many millions of stars. One of the leading ground-based surveys is the SuperWASP project. We present the initial results of a survey of…