About us      Divisions     Telescopes     Science     Publications     Education     Service     Contacts

Scientific achievements, Galaxy sector

Discovery of enrichment of the envelopes of post-AGB stars with heavy metals
As a result of monitoring carried out at the BTA telescope, a new phenomenon was discovered in the optical spectra of post-AGB supergiants with an emission at 21 ?m and an overabundance of carbon and heavy metals in the atmospheres - the splitting of the strongest absorption lines. The effect is strongest in the high-latitude supergiant V5112 Sgr, in whose spectrum the BaII lines are split into three components. It is shown that the short-wavelength components of the split absorptions are formed in the structured circumstellar envelope. Thus, we discovered for the first time the enrichment of the stellar envelope with heavy metals synthesized by the s-process.
(Contact - Klochkova V.G.).
Published:
V.G.Klochkova. Detection of heavy-metal lines in the spectrum of the circumstellar envelope of a post-AGB star. Astronomy Letters, 2009, 35, No.7, pp.457-465.
V.G.Klochkova. High-latitude supergiant V5112 Sgr: Enrichment of the envelope with heavy s-process metals. Astronomy Letters, 2013, 39, No.11, pp.765-775.

Detection of sub-second spikes in the giant optical flare of UV Ceti
About a dozen spikes with a duration of 0.6-1.2 seconds were discovered for the first time during the monitoring of the flare star UV Ceti at the 6-m telescope equipped with the MANIA complex. The events are localized in the vicinity of the maximum of the giant flare and may have a synchrotron or bremsstrahlung nature.
(Contact - G.M.Beskin).
The result was reported at the European Week of Astronomy and Space Science 2013 (EWASS) conference, Turku, June 8-13, 2013. The publication is in preparation to appear in MNRAS.

Discovery of new binary and multiple star systems with magnetic components
Speckle interferometric observations of 273 magnetic stars were carried out at the 6-m BTA telescope of SAO RAS. We fully investigated the northern part (δ>-30^o) of the sample of stars with confirmed global magnetic fields. As a result of high angular resolution (R=0.0022") observations in a 4.4x4.4" field, 28 new binary and 2 triple stars were discovered. We resolved 63 objects into individual components: 58 binary and 5 triple systems. Almost half of the resolved systems were discovered for the first time. Some of these objects may turn out to be subsystems in higher-order stellar systems.
(Contact - Rastegaev D.A.).
Published:
D.A.Rastegaev, Yu.Yu.Balega, V.V.Dyachenko, A.F.Maksimov, E.V.Malogolovets, "Speckle-interferometry of magnetic stars at the BTA. II. Results of 2010-2012 observations", Astrophysical Bulletin, 2014, Volume 69, Issue 1

  Archive