Image of a White Dwarf in the CH Cygnus Binary.
Using speckle interferometry on the BTA, we for the first time obtained an image of an accreting white dwarf in an unusual symbiotic binary óî Cyg. From the measurements of the angular separation between the components of the pair (0.042") and the brightness difference (2m), we determined the period of orbital movement, 15.6 years, and the component masses: 2.0 M for the red giant, and 0.7 M for the white dwarf. We found that the collimated gas outflow from the system does not coincide with the orbit surface normal of the binary.
(For contacts: Yu.Yu.Balega)
New Wolf-Rayet Type Star.
A new nitrogen sequence Wolf-Rayet Star was discovered. It belongs to the rare subtype, intermediate between the LBV and WR, in the winds of which the hydrogen is still present. The star is located at the centre of a ring IR nebula with the diameter of 2pc. We determined the star's parameters: T=40kK, its shell has only 20% of hydrogen, Av=7.4m, lgL/L=5.3, mass los rate 10-4.7M a year, distance 4.2kpc. It was discovered that the peculiar velocity of the star is about 50km/s, and that it was discarded from a young star cluster.
In collaboration with SAI MSU, the University of Potsdam and the University of Bochum (Germany).
(For contacts: Fabrika S.N.)
Magnetic fields of Chemically Peculiar Stars.
Based on the observational data from the 6-m telescope and from other sources, it was shown with high reliability that chemically peculiar stars with strong depressions in their continuum energy distributions possess the magnetic fields and rotation periods 2 and 3 times larger, respectively, than the stars with weak depressions. This is an additional evidence for the fact that slow rotation of a star is an important factor, contributing to the formation of the phenomenon of magnetic chemically peculiar stars.
(For contacts: Romanuyk I.I.)
Radio Flare Maxima Drift in LSI+61d303 Microquasar.
Comparing the RATAN-600 2003 and 2009 observations of the LSI+61d303 microquasar light curves within 5 and 6 orbital periods (P=26.5d), it was discovered that the mean flare maxima over a period took place at the orbital period phases 0.500.05 and 0.700.05, taken the superorbital period phases of (P=1667d) 0.65 and 0.0, respectively. In both sets the maxima arrived later at low frequencies. The reason of synchrotron emission modulation by the superorbital period is, possibly, a precession of jet ejections.
(For contacts: S.A.Trushkin)