170 datasets found

It remains difficult to interpret the near-IR emission of young stellar populations. One main reason is our incomplete understanding of the spectra of luminous red stars. This...

The U BV photometry and low-resolution spectroscopy for the semiregular variable AI CMi, a candidate for post-AGB objects, performed in 1996-2016 and 2000-2013, respectively,...

We present the results of our UBV and JHKLM photometry for the semiregular pulsating variable V1027 Cyg, a supergiant with an infrared excess, over the period from 1997 to 2015...

We present photoelectric and spectral observations of a hot candidate proto-planetary nebula early B-type supergiant with emission lines in spectrum-IRAS 19336-0400. The light...

We analyze long-term UBV observations and ASAS-3 photometry for five candidates for protoplanetary nebulae - F and G supergiants with infrared excesses at high Galactic...

We present new photometric data and analyze long-term UBV observations of three candidates for protoplanetary nebulae - F supergiants with infrared excesses at high Galactic...

We have analyzed our long-term (1995-2008) JHKLM photometry for three variable RV Tau supergiants. It follows from this analysis that: the amplitude of the JHK brightness...

We present new results of our UBV photometry for HD 179821=V1427 Aql, an F supergiant with an infrared excess, from 2000 to 2008. The semiregular low-amplitude...

New photometric observations of the variable star FG Sge, a rapidly evolving planetary nebula nucleus, were performed in 2003-2008. On 230 nights, we obtained 86 UBV and 155...

We present our long-term photometric and spectroscopic observations of a high-latitude B supergiant with an infrared excess - the protoplanetary nebula IRAS 18062+2410. Our UBV...

The results of UBV photometric and spectroscopic observations of the early B supergiant with an IR excess IRAS 19200+3457.

Systematic UBV observations of six variable post-AGB supergiants in 1991-1999 are presented.

We present a high resolution (R=90000) spectral atlas of the F5Ib star Alpha Per covering the 3810-8100{AA} region. The atlas, based on data obtained with the aid of the echelle...

A detailed non-LTE study on the abundances of C, N, O, S, and Zn was carried out for five F-G supergiants of suspected post-AGB candidates with IR excesses (HD 112374, HD...

Almost all massive stars explode as supernovae and form a black hole or neutron star. The remnant mass and the impact of the chemical yield on subsequent star formation and...

Red supergiants represent the most common final stage of the evolution of stars with initial masses between 8 and 30-35 times the mass of the Sun. During this phase of lifetime...

Optical spectra taken in 1997-2008 are used to analyze the spectral peculiarities and velocity field in the atmosphere of the peculiar supergiant 3 Pup.

We aim to identify and characterise binary systems containing red supergiant (RSG) stars in the Small Magellanic Cloud (SMC) using a newly available ultraviolet (UV) point...

The rate at which mass is lost during the Red Supergiant evolutionary stage may strongly influence how the star appears. Though there have been many studies discussing how RSGs...

A line-depth ratio (LDR) of two spectral lines with different excitation potentials is expected to be correlated with the effective temperature (T_eff_). It is possible to...