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Evidence for the connection between turbulent gas motions and star
formation in dwarf galaxies
Observations with the 6-m telescope of SAO RAS have increased by several
times the number of dwarf galaxies with constructed ionized gas velocity
fields. We show that velocity dispersion is not related to the virial
motions in the gravitational potentials of galaxies (a point of view
that dominates in the literature), but is determined by the energy
"injected" into the interstellar medium with ongoing star formation.
This relation has a universal nature in the widest range of galactic
masses and luminosities.
(Contact - Moiseev A.V.).
Published:
Moiseev A.V. "Ionized gas rotation curves in nearby dwarf galaxies",
Astrophysical Bulletin, 2014, Volume 69, Issue 1
Moiseev A.V., Tikhonov A.V., Klypin A.A. "What controls the ionized gas
turbulent motions in dwarf galaxies", submitted to MNRAS
Updated Catalog of Nearby Galaxies
A catalog of 869 nearby galaxies (distance < 11 Mpc) was created based
on the constantly updated Local Volume galaxy
database. This sample is essential for the studies of the formation
and evolution of galaxies and structures in the Universe. Only in the
Nearby Universe is a detailed study of all the variety of the world of
galaxies possible. Approximately 300 galaxies in the sample have
high-accuracy distance estimates, allowing one to study the distribution
and kinematics of matter on a scale of up to 11 Mpc.
(Contact - Karachentsev I.D.).
Published:
Updated Nearby Galaxy Catalog, 2013, AJ, 145, 101
Determination of the mass of a supermassive black hole in AGN Mkn6
based on spectro-polarimetric observations
A unique set of linear polarization measurements in the spectrum of the
Seyfert galaxy Mkn6 was obtained with the 6-m telescope. It is shown for
the first time that an analysis of the dependence of the polarization
angle on the velocity in the hydrogen line profiles, which are determined
by the emission of gas in the broad line region (BLR) in the vicinity of
the massive AGN, allows to determine directly from observations the type
of motion in the BLR, which in the case of Mkn6 proved to be Keplerian
at distances less than 0.02 pc from the nucleus. The lower mass limit
for the supermassive black hole in AGN Mkn6 was determined as 150 million
solar masses.
(Contact - Afanasiev V.L.).
Published:
ÁrXiv:1310.1179
Optical spectroscopy of ultra-luminous X-ray sources (ULX)
Based on the results of optical spectroscopy performed with BTA and Subaru,
and on the published data, we discovered that all the ULX objects ever
spectroscopically studied have the same rare type of spectrum: WNL or
LBV in the hot state. We discovered strong night-to-night emission line
variability of up to 350 km/s. Neither a WNL optical star nor an
intermediate-mass black hole with a standard disk can explain our
optical spectra. The observed spectra correspond to a supercritical
accretion disk around a stellar-mass black hole (SS433 type). The
investigated ULX objects should have accretion rates onto the black
hole 1.5-6 times lower than in the case of SS433.
(Contact - S.N.Fabrika).
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