Important scientific
achievements
1) A new
bright galaxy of the Local Group VV124 (UGC4879) is found. The last discovery
of such a bright galaxy of the Local Group was made 40 years ago. Taking into
account all the works of recent years on the search for nearby galaxies, it can
be stated that the VV124 is the latest found bright galaxy belonging to the
Local Group of galaxies.
Kopylov A.I., Tikhonov
N.A., Fabrika
S.N., Drozdovsky I.O., Valeev A.F., MNRAS
Lett, V. 387, Issue 1, L45, 2008.
Tikhonov
N.A., Fabrika S.N., Sholukhova O.N., Kopylov
A.I., Astronomy Letters, V. 36, Issue 5, p. 309, 2010.
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Fig. 1.
Galaxy VV124 (BTA image). |
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2) Within a
few decades, there was a popular hypothesis about the possibility for primary
young galaxies with low metalicity and the first wave of star formation in the
history of these galaxies to be found in the relatively close neighborhood of
our galaxy. As a sample of galaxies of this type the 1Zw18 galaxy has been
always called for. Using the Hubble Space Telescope images, we carried out stellar
photometry for 1Zw18 and for the first time we had found in this galaxy red
giants with the age of several billion years, which immediately rejected the
hypothesis that the galaxy was young.
Tikhonov N.A., Astronomy Letters, V.33, Iss.3, p.137, 2007.
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3) Dynamical
and photometrical (near-infrared, in K-band) characteristics of 183 groups and
clusters of galaxies located in the regions of superclusters of galaxies
Hercules, Leo, Ursa Major, Bootes, Corona Borealis and outside superclusters
having radial velocities in the interval 0.012<z<0.09 (+ Virgo cluster)
based on the archival data from the SDSS, 2MASX, NED catalogues are determined.
The IR-luminosity of the systems of galaxies mainly corresponding to the
luminosity of old stars from early-type galaxies allows to the first approximation
to estimate their masses according to the correlation between dynamical mass
and IR-luminosity. For systems of galaxies in the regions of the Hercules
and Leo superclusters the dwarf-to-giant
ratio of galaxies in the r-band is evaluated, and it is found that this ratio
increases with increasing X-ray luminosity at log LX > 43.5 erg/s.
Kopylova
F.G., Kopylov A.I., Ast. Bull. 64, 1, 2009.
Kopylova F.G.,
Kopylov A.I.,
2011, Astron. Lett., 37, 219, 2011.
Kopylova F.G., Astroph.
Bull. 68, 253, 2013.
Kopylova F.G.,
Kopylov A.I., Astron. Lett.,
39, 1, 2013.
Kopylova F.G.,
Kopylov A.I., Ast.
Bull. 70, 123,
2015.
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Fig. 3. K-luminosity of 183
galaxy groups and clusters depending on their dynamic mass M200 is shown. Blue squares show x-ray clusters of
galaxies with the dispersion of radial velocities >400 km/s, red squares –
groups with the dispersion of radial velocities <400 km/s, and cyan squares
show systems without LX
measurements.
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4) Using
the data of catalogues of SDSS DR7-8 we investigated the peculiar motions of
groups and clusters of galaxies in the regions of Ursa Major, Hercules, Leo and
Bootes superclusters. For this purpose, we compiled a samples of ealy-type
galaxies in them and determined the fundamental plane distances and peculiar
velocities. For all superclusters of galaxies is Hubble's law between the
radial velocity and distance obtained by the fundamental plane of early-type
galaxies. Within their regions the following peculiar motion rms deviations
along the line of sight are observed: 736±50 km/s in Hercules, 625±70 km/s in
Leo, 370±50 km/s (rich clusters) in Bootes and 290±120 km/s in UMa.
Kopylova
F.G., Kopylov A.I.,
Astron. L. 33, 211, 2007.
Копылова Ф.Г.,
Копылов А.И., Отчет
САО РАН, 2012.
Kopylova F.G.,
Kopylov A.I.,
2014, Astron. L. 40, 595, 2014.
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Fig. 4. The map of distribution of galaxies and clusters in the region of Hercules and
Leo superclusters with radial velocities in the range of cz = 8000–13000 km/s.
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5) The study was performed
of four complex (bimodal) Abell clusters with difference of radial velocities
between the subclusters of about 3000 km/s, which may be due either to the
gravitational interaction between very massive clusters at a collision on the
line close to the line-of-sight or the projection along the line-of-sight of
non-connected clusters. Using observational data from the 1-m telescope of SAO
RAS and data of the SDSS catalogue we measured photometric relative distances
(by the Kormendy relation and the fundamental plane) and revealed the structure
of clusters A1035, A1569, A1775 and A1831. It is found that subclusters in
these clusters are not bound gravitationally, and for them the Hubble law is
obeyed.
Kopylov
A.I., Kopylova F.G., Ast. Bull.
62, 311, 2007.
Kopylov A.I.,
Kopylova F.G., Ast.
Bull. 64, 207, 2009.
Kopylov A.I.,
Kopylova F.G., Ast. Bull. 65, 205, 2010.
Kopylov A.I.,
Kopylova F.G., Ast. Bull.
67, 17, 2012.
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Fig. 5. The Hubble diagram (velocity [zspec]
– distance [zphot]) is
shown for four bimodal clusters of galaxies (A-components to left, B-components
to right), and for the cluster A1589, the nearest rich neighbour (12 Mpc) of the
cluster A1569A.
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