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Scientific achievements, Galaxy sector

In course of a long-term program of spectroscopy with a 6m telescope together with echelle spectrographs NES and PFES, spectra of all white hypergiants of the Galaxy with V<12^m, δ>-20^o were obtained. An increase in star brightness is followed by a decrease in asphericity and wind velocity to the point where stationary and even accreting fraction of the wind appears in extremely bright objects together with a flowing out fraction. The increase of substance loss rate with the increase of luminosity is provided by increasing of density.

Based on an analysis of observations obtained with BTA and on the published data it was found that degree of abnormality of energy distribution in continuum of magnetic chemically peculiar stars increases with an increase of their rotation period. Fast rotators have a complex field structure. The data could be explained by the relic theory: magnetic fields were formed from interstellar medium together with a star.

It has been demonstrated for the first time that a peculiar nova star V838 Mon is a binary system and that it has a chemical composition similar to that of the Sun. A burst of a nova star is accompanied by light echo, the boundary of which is propagating with a superluminal speed. The object does not belong to stars of post-AGB class at helium burst stage but it is assigned to a new class of peculiar nova stars with K-M spectra in bursts. These stars do not pass a nebular stage. Three such objects are known.
In cooperation with SAI MSU.

Using data of infrared observations made on the BTA with close to diffractional angle resolution of central region of a nebula which surrounds a massive protostar IRAS 23151+5912 with an age of about 20 thousand years, it was demonstrated that arcuate details at the nearest proximity to the source centre are caused by the impact of a powerful jet efflux onto the environment. It leads to the formation of a conical cavity around the protostar. Bolometric luminosity of the young object is 105 times higher than that of the Sun, and its mass is 25 solar masses.
In cooperation with Bonn Institute for Radioastronomy (Germany) and Harvard- Smithsonian Center for Astrophysics (USA).

Weak high-velocity (up to 400-500 km/s) details of Hα line were found in a pulsar nebula during observations of the vicinity of the pulsar PSR B1951+32 in the old supernova remnant CTB 80. The observations were carried out by the 6m telescope of SAO RAS with Fabry-Perot interferometer. By means of pulsar nebula kinematics research and by analysis of its morphology in Hα, [SII], [OIII] lines using archive data of Hubble telescope, the direction of the pulsar motion and its possible spatial velocity (500 km/s) are precised. In the overall scheme of CTB 80 which takes into account last observational data in optical and radio rangese, a high spatial velocity of the pulsar does not contradict its location within a dense shell of the old supernova remnant.
In cooperation with SAI and ITEP.

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