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The List of Possible Double and Multiple Open Clusters between Galactic Longitudes 240° and 270°
Casado, J.
Abstract—This work studies the candidate double and multiple open clusters (OCs) in the galactic sector from l = 240° to l = 270°, which contains the Vela-Puppis star formation region. To do that, we have searched the most recent and complete catalogues of OCs by hand to get an extensive list of 22 groups of OCs involving 80 candidate members. Gai…
Ethynyl Around the HII Regions S255 and S257
Kirsanova, M. S.; Punanova, A. F.; Buslaeva, A. I.
We present the results of the ethynyl (C2H) emission line observations towards the S255 and S257 HII regions and the molecular cloud between them. Radial profiles of line brightness, column density, and abundance of C2H are obtained. We show that the radial profile of the ethynyl abundance is almost flat towards the HII regio…
Principal Component Analysis for Estimating Parameters of the L1287 Dense Core by Fitting Model Spectral Maps into Observed Ones
Pirogov, L. E.; Zemlyanukha, P. M.
An algorithm has been developed for finding the global minimum of a multidimensional error function by fitting model spectral maps into observed ones. Principal component analysis is applied to reduce the dimensionality of the model and the coupling degree between the parameters, and to determine the region of the minimum. The k-nearest neighbors …
Comparison of the Orbital Properties of the Milky Way Globular Clusters from the Data of the Gaia DR2 and EDR3 Catalogs
Bobylev, V. V.; Bajkova, A. T.
We provide new values of the orbital parameters of 152 globular clusters, which are calculated using the new mean proper motions obtained from the Gaia EDR3 catalog data. The orbits were integrated 5 Gyr back in an axisymmetric three-component potential with a spherical bulge, disk component, and spherical dark halo in the Navarro-Frenk-White form…
Destruction of Galaxies as a Cause of the Appearance of Stellar Streams
Vereshchagin, S. V.; Tutukov, A. V.; Sizova, M. D.
The interaction of galaxies in clusters with the intergalactic gaseous medium and other galaxies is considered. The causes for the appearance of gaseous and stellar "tails" and stellar "copies" of galaxies during their movement in a dense gaseous medium in the cores of clusters and during the tidal destruction of colliding galaxies are studied. Th…
Minimally Modified Gravity Fitting Planck Data Better Than ΛCDM
Pookkillath, M. C.
Here we present cosmology of a class of Minimally Modified Gravity theory dubbed as $f(H)$ theory. After introducing a concrete model for the free function, we find that this cosmological model fits Planck data better than $Λ $CDM.
Analysis of Study Results of the Polar Coronal Hole on the Sun According to Observations in the Microwave Wavelength Range
Golubchina, O. A.
An overview is presented of the main results of the study of the polar coronal hole over the North pole of the Sun based on observations of the solar eclipse on March 29, 2006, using the RATAN-600 radio telescope in a wide cm-range of wavelengths (1.03, 1.38, 2.7, 6.2, 13.0, 30.7 cm) along with observational and theoretical data about the properti…
The First Light Curve Solution of GW Leo and Refined Ephemeris of Two Contact Binary Systems
Poro, A.; Davoudi, F.; Lashgari, E. +6 more
We performed the first light curve analysis of GW Leo and a new ephemeris is obtained for QT Boo. The light curve investigation also yields that the system GW Leo is a contact W UMa eclipsing binary with a photometric mass ratio of q = 0.44 ± 0.03, a fillout factor of f = 59.6%, and an inclination of 50.77° ± 0.09°. Due to the O'Connell effect whi…
Improving the Orbits of Four Visual Binaries Using Gaia DR2 Data and Observations with the 26-inch Refractor of Pulkovo Observatory
Romanenko, L. G.; Izmailov, I. S.
We use a modified method of the apparent motion parameters (AMP), in which the initial data from the Gaia DR2 catalog are not only high-precision coordinates, parallaxes, and radial velocities of the components of the studied wide binary stars, but are also their proper motions. The coincidence of the AMP orbits obtained both from the Gaia DR2 dat…
How We Can Account for Type Ia Supernova Environment in Cosmological Analysis
Pruzhinskaya, M. V.; Pauna, N.; Novinskaya, A. K. +1 more
Among the other types of supernovae, Type Ia Supernovae (SNe Ia) have less luminosity dispersion at maximum light and show higher optical luminosities. These properties allow to use them as cosmological distance indicators that led to the discovery of the accelerating expansion of the Universe. However, even after the luminosity correction for str…