New LBV discovered in the Galaxy
As a result of spectroscopy of stars with circular nebulae from the Spitzer survey (24 microns) on the BTA a new luminous blue variable star (LBV) was discovered in our Galaxy (MN112). These are very rare (there are about 10 of them known in the Galaxy) and most massive stars, locateŚ on the short stage of evolution. The spectra of MN112 and the famous LBV P Cyg are almost identical. The I-magnitude has increased by 0.4 over the past 17 years. The absorption of light to the MN112 is 8.4-8.9 mag.
In collaboration with the SAI MSU, the South African Astronomical Observatory (SAAO)
Published: MNRAS, 2010, vol.405, p.520
Flare activity of Cygnus X-3 microquasar from radio waves to
RATAN-600 has registered powerful radio flares from a microquasar Cygnus X-3. During these flares, hard gamma radiation (AGILE-GRID) was detected with the energies of > 100 MeV (for the first time from a star in our Galaxy). It is shown that powerful radio bursts of the microquasar, which were caused by the ejections of matter at the speeds close to the speed of light, occur in a certain "super soft" state of the X-ray radiation (RXTE PCA).
In collaboration with the INAF/IASF-Bologna, Italy; INAF/IASF-Roma, Italy; the Smithsonian Center for Astrophysics, USA; Cavendish Laboratory, UK; TKK/Metsohovi Radio Observatory, Finland.
(Contacts: Trushkin S.A.)
From the materials of three works: Nature, 2009, 462, 620-623; MNRAS, 2010, 406, 307-319; A & A, 2011 (submitted)
Speckle interferometry of magnetic stars
We have carried out interferometric observations of a sample 160 chemically peculiar Ap/Bp stars with proven global magnetic fields. Thirty-eight systems were resolved into individual components. As a result of our studies, we conclude that, contrary to the current views, the proportion of double and multiple magnetic stars does not differ from their non-magnetic counterparts.
(Contacts: Rastegaev D.A.)
Radial gradient of magnetic field in the atmospheres of chemically
As a result of BTA observations of 23 chemically peculiar stars with strong magnetic fields, it was found that in 22 of them the longitudinal magnetic field, measured by the Zeeman shifts in the hydrogen line cores are systematically lower than the value measured from metal lines. The observed effect may indicate the presence of a radial gradient of magnetic field in stellar atmospheres and a more complicated magnetic field structure than a simple dipole.
Discovery of pulsar pairs - possible components of broken binary systems
Obtaining the radio pulsar trajectories by their kinematic characteristics distances of closest approach in the past were found for 20 pairs of rather young objects with measured distances and proper motions. The analysis of the probability of these encounters revealed that radio pulsars from 6 pairs could previously be the companions of the binaries broken up in supernova explosions.
In collaboration SAI MSU