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Detection of galaxies with large peculiar velocities
It was discovered that nearby galaxies with large negative peculiar
velocities are distributed quite inhomogeneously over the sky. A half
of these rapidly moving objects are concentrated in a small region of
the sky, called the Coma I Cloud. The Hubble flow around this complex
reveals a Z-shaped effect of the infall of galaxies on the "cloud" with
an amplitude of about 700 km/s.
This phenomenon may be caused by the presence of a "dark attractor"
in the Coma I with a mass of about 400 trillion solar masses at the
distance of 15 Mpc away from us. The kinematics of galaxies around
the Coma I may be influenced by the presence between the Virgo and
Coma clusters of galaxies of a giant cosmic void, the walls of which
are receding from its center. The "dark attractor" may be a new type
of astronomical objects, previously unknown.
(Contact - I.D.Karachentsev)
Published: ApJ, 2011, v.743, p.123
New galaxies with polar rings
Based on data from the Sloan Digital Sky Survey (SDSS) and the Galaxy
Zoo project a new catalog significantly (by three times) increasing
the number of known candidates in polar ring galaxies is compiled.
This is a unique class of extragalactic objects that reveal external
rings or disks of gas, dust and stars, rotating in a plane roughly
perpendicular to the disk of the central galaxy.
The new catalog contains 275 galaxies. Spectral observations of several
candidates, conducted at the 6-m BTA telescope of the SAO RAS in order
to study their internal kinematics, have confirmed the existence of polar
structures in 8 galaxies.
In collaboration with the UrFU and the St. Petersburg State University
(Contact - A.V. Moiseev)
Radio galaxy RC J0311+0507, a unique object of the early Universe
An object of the early Universe (z=4.514) RC J0311+0507, having no analog,
detected within the "Big Trio" program (RATAN-600, VLA, BTA), was studied
in detail by the VLBI methods (EVN, MERLIN; angular resolution of 0.35")
to refine the physical parameters of the radio galaxy. The uniqueness
of the object is its extremely high luminosity in the radio range and
large radio to optical luminosity ratio, which indicates the presence
of a giant black hole
at the center of the host galaxy with a mass in excess of
1010M
,
close to the limiting mass in the observable Universe. The estimation
of the stellar population age in the host galaxy via the multicolor
photometry (BTA) and new infrared data (UKIRT, 2011), amounting to
0.8 Gyr results in the moment of its formation when the universe was
about 0.5 milliard years old (z~10).
In collaboration with a group of researchers from the UK, Holland, ASC LPI.
(Contact - O.P. Zhelenkova)
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