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  • Measuring Plumb-Line Deviations with a Digital Astrometer at the Moscow Gravitational Attraction
    Astron. Rep. (IF 1.164) Pub Date : 2020-10-10
    M. M. Murzabekov, V. F. Fateev, P. A. Yuzefovich

    Abstract The paper presents the component measurement results of plumb-line deviations (PLDs) with a digital astrometer at the Moscow gravitational anomaly (attraction). The anomaly was first discovered in the 1850s by B. Ya. Schweitzer, Professor of Astronomy of the Moscow University. The paper is based on the conference talk made at “Astronomy yesterday, today, tomorrow” (Sternberg Astronomical Institute

    更新日期:2020-10-11
  • Evolution of a Viscous Protoplanetary Disk with Convectively Unstable Regions. II. Accretion Regimes and Long-Term Dynamics
    Astron. Rep. (IF 1.164) Pub Date : 2020-10-10
    L. A. Maksimova, Ya. N. Pavlyuchenkov, A. V. Tutukov

    Abstract In this article, we proceed to study convection as a possible factor of episodic accretion in protoplanetary disks. Within the model presented in Article I, the accretion history is analyzed at different rates and areas of matter inflow from the envelope onto the disk. It is shown that the burst-like regime occurs in a wide range of parameters. The long-term evolution of the disk is also modeled

    更新日期:2020-10-11
  • Evolution of the OH and H 2 O Maser Emission in the Active Star-Forming Region IRAS 05358+3543 (S231)
    Astron. Rep. (IF 1.164) Pub Date : 2020-10-10
    N. T. Ashimbaeva, P. Colom, V. V. Krasnov, E. E. Lekht, M. I. Pashchenko, G. M. Rudnitskii, A. M. Tolmachev

    Abstract We present the results of our observations of the star-forming region located in the Perseus arm and associated with the Sharpless nebula S231 in the lines of H2O at a wavelength of 1.35 cm and OH at a wavelength of 18 cm obtained with the Pushchino 22-m radio telescope (Russia) and the Nançay Large Radio Telescope (France), respectively. We provide a catalog of H2O maser spectra in the period

    更新日期:2020-10-11
  • Physical and Chemical Properties of Galactic Global Clusters with Various Origins Identified from the Gaia DR2 Data
    Astron. Rep. (IF 1.164) Pub Date : 2020-10-10
    V. A. Marsakov, V. V. Koval’, M. L. Gozha

    Abstract The differences in the relationships between the physical parameters and the chemical-element abundances in accreted globular star clusters and those formed inside the Galaxy have been investigated. The information on the supposed formation sites of the clusters based on the Gaia DR2 data is borrowed from the literature. Those sources estimate the probability of belonging to the Galactic bulge

    更新日期:2020-10-11
  • Formation of Stellar Streams Due to the Decay of Star Clusters, OB Associations, and Galaxy Satellites
    Astron. Rep. (IF 1.164) Pub Date : 2020-10-10
    A. V. Tutukov, M. D. Sizova, S. V. Vereshchagin

    Abstract This paper presents a scenario of the evolution of OB associations and star clusters from formation to decay, in the process of which they turn into stellar streams moving in the disk and stellar “rings” around the galactic center. The scenario also includes the formation of stellar streams by galaxies absorbing their dwarf satellite galaxies. The simplest spatial kinematic models of evolution

    更新日期:2020-10-11
  • Kinetic Calculations of the Charge Exchange Efficiency for Solar Wind Protons in the Extended Martian Hydrogen Corona
    Astron. Rep. (IF 1.164) Pub Date : 2020-10-10
    V. I. Shematovich, D. V. Bisikalo

    Abstract— Model calculations of the charge exchange efficiency for solar wind protons colliding with hydrogen atoms of the extensive Martian corona are presented. It is shown that the energy spectrum of hydrogen atoms penetrating in the Martian atmosphere is identical to the spectrum of protons of the unperturbed solar wind. The charge exchange efficiency varies from 2 to 4% depending on the boundary

    更新日期:2020-10-11
  • Solar Quadrupole in Tensor Description
    Astron. Rep. (IF 1.164) Pub Date : 2020-10-10
    A. S. Shibalova, V. N. Obridko, D. D. Sokolov, V. V. Pipin

    Abstract The cyclic variations in the quadrupole component of the solar magnetic field is studied in tensor description. The results are consistent with the classical description of the quadrupole using spherical functions, and the mathematical apparatus of tensor algebra allows one to compare the observed changes in the magnetic quadrupole and the changes predicted by the dynamo theories. In conclusion

    更新日期:2020-10-11
  • Secular Evolution of Rings around Rotating Triaxial Gravitating Bodies
    Astron. Rep. (IF 1.164) Pub Date : 2020-10-10
    B. P. Kondratyev, V. S. Kornoukhov

    Abstract The problem of the secular evolution of a thin ring around a rapidly rotating triaxial celestial body is formulated and solved. The technology for calculating secular perturbations is based on two formulas: the azimuthally averaged force field of the central body and the mutual energy \({{W}_{{{\text{mut}}}}}\) of this body and a Gaussian ring. With \({{W}_{{{\text{mut}}}}}\) instead of the

    更新日期:2020-10-11
  • Parameter Comparison of Several Types of Pulsars
    Astron. Rep. (IF 1.164) Pub Date : 2020-09-23
    I. F. Malov, H. P. Marozava

    Abstract— We have carried out a comparative analysis of the parameters of two samples of radio pulsars. The first of them is characterized by periods \(P > 2\) s, the second one—by the surface magnetic fields \({{B}_{s}} > 4.4 \times \) 1013 G. The purpose for selecting these values is for the understanding the origin of the difference between normal pulsars and anomalous X-ray pulsars (AXP) and gamma-repeaters

    更新日期:2020-09-23
  • Motion of a Pair of Gravitating Bodies in Dark Energy Presence: Small Deviations from Keplerian Motion
    Astron. Rep. (IF 1.164) Pub Date : 2020-09-23
    A. I. Neishtadt, G. S. Bisnovatyi-Kogan

    Abstract The problem of the motion of two gravitating bodies in the presence of dark energy (DE), considered as a perturbing factor, is investigated. In addition to the orbit precession frequency obtained in previous studies, the correction to the orbital motion frequency was calculated, and the oscillations of the semi-major axis and the eccentricity of the orbit caused by the influence of DE were

    更新日期:2020-09-23
  • Development of Methods for Navigational Referencing of Circumlunar Spacecrafts to the Selenocentric Dynamic Coordinate System
    Astron. Rep. (IF 1.164) Pub Date : 2020-09-23
    A. O. Andreev, Yu. A. Nefedyev, N. Yu. Demina, L. A. Nefediev, N. K. Petrova, A. A. Zagidullin

    Abstract The initial form of present-day space optical observations contain considerable geometrical and brightness distortions. This problem can be solved based on geometrical correction and transformation of reference object coordinates into commonly accepted cartographic projections. In this work, the method of coordinate transformation to the reference selenocentric dynamic system by using a base

    更新日期:2020-09-23
  • Central Field Motion with Perturbing Acceleration Varying According to the Inverse Square Law in the Reference Frame Associated with the Radius Vector
    Astron. Rep. (IF 1.164) Pub Date : 2020-09-23
    T. N. Sannikova, K. V. Kholshevnikov

    Abstract The motion of a point with zero mass under the action of attraction to the central body \(\mathcal{S}\) and perturbing acceleration \({\mathbf{P}}{\kern 1pt} ' = {\mathbf{P}}{\text{/}}{{r}^{2}}\), inversely proportional to the square of the distance to \(\mathcal{S}\), is considered. It is assumed that \({\mathbf{P}}{\kern 1pt} '\) is small in absolute value compared to the main acceleration

    更新日期:2020-09-23
  • Deflecting an Asteroid with a Low-Thrust Tangential Engine to the Orbit
    Astron. Rep. (IF 1.164) Pub Date : 2020-09-23
    K. V. Kholshevnikov, D. V. Milanov, K. I. Os’kina, V. B. Titov

    Abstract In order to solve the problem of deflecting a dangerous asteroid from a collision orbit with the Earth, using a low-thrust engine directed tangentially to the trajectory is considered. The engine can be mounted on the asteroid or on a “gravity tractor.” The purpose of this study is to establish the fundamental possibility of steering away an asteroid to a safe distance over times of approximately

    更新日期:2020-09-23
  • Suggestion for Search of Malononitrile (CH 2 (CN) 2 ) in a Cosmic Object: Potential Spectral Lines
    Astron. Rep. (IF 1.164) Pub Date : 2020-09-23
    M. K. Sharma, M. Sharma, S. Chandra

    Abstract Though accurate laboratory studies of malononitrile (CH2(CN)2), a dinitrile molecule, have been carried out from time to time, and it has large electric dipole moment \(\mu = 3.735\) D, its detection in a cosmic object is still awaited. Because of two equivalent hydrogen atoms, it has ortho and para species. In order to obtain information about some potential spectral lines of malononitrile

    更新日期:2020-09-23
  • Binary Star Population with Common Proper Motion in Gaia DR2
    Astron. Rep. (IF 1.164) Pub Date : 2020-09-23
    S. A. Sapozhnikov, D. A. Kovaleva, O. Yu. Malkov, A. Yu. Sytov

    Abstract— We describe a homogeneous catalog compilation of common proper motion stars based on Gaia DR2. A preliminary list of all pairs of stars within the radius of 100 pc around the Sun with a separation less than a parsec was compiled. Also, a subset of comoving pairs, wide binary stars, was selected. The clusters and systems with multiplicity larger than 2 were excluded from consideration. The

    更新日期:2020-09-23
  • Deuterium Fractionation in the Oph-H-MM1 Dense Core of the L1688 Low Mass Star-Forming Region
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    I. V. Petrashkevich, A. F. Punanova, P. Caselli, J. Pineda, A. Pon, R. Friesen

    Abstract Molecular clouds fragment to form dense cores, which are the first stage of star formation. Such objects are cold, with temperature of ~10 K and density of \({{10}^{4}}{-} {{10}^{7}}\) cm–3, with predominance of thermal motions and high deuterium fraction. These objects give us information about the initial conditions of star formation and thus they are very important to understand this process

    更新日期:2020-08-31
  • Impact of the Small-Scale Spatial Distribution of Dust Particles on the Chemical Evolution of the Diffuse Interstellar Medium
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    V. A. Sokolova, A. I. Vasyunin, A. B. Ostrovskii, S. Yu. Parfenov

    Abstract In this work we analyze the effect of gas-dust clumps, possibly formed in the interstellar medium due to instability, described in [10], on the chemical evolution of the diffuse interstellar medium. For this purpose we calculate chemical evolution with common parameters of diffuse interstellar medium (ISM). It is shown that abundances of most observed molecules are higher in a model of the

    更新日期:2020-08-31
  • Probing Modified Gravity with the Structures Maximum Dimensions
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    A. Del Popolo

    Abstract By using an extended spherical collapse model taking into account the effects of shear, vorticity, and dynamical friction we found the relationship between the turnaround radius, \({{R}_{t}}\), and mass, \({{M}_{t}}\), in \(\Lambda \)CDM and dark energy scenarios. We get a more general formula than that usually described in literature, showing a dependence of \({{R}_{t}}\) from shear, vorticity

    更新日期:2020-08-31
  • Solar Gamma-Ray Flares and Activity Complexes
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    V. M. Tomozov, S. A. Yazev, E. S. Isaeva

    Abstract Strong flare events with an extended phase of gamma ray emission from the catalog by Share et al. have been analyzed in order to explain the characteristics of the impulsive and extended phases of such flares and reveal their connection with activity complexes and coronal holes. It is shown that 74% of such events are closely related to activity complexes. It has been qualitatively demonstrated

    更新日期:2020-08-31
  • Diffusion Ionised Gas in the Directions of the Supernova Remnant Kes 79 and Pulsar B1849+00
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    A. V. Pynzar

    Abstract Based on the spatial correlation between the distributions of diffuse ionized gas (DIG) and the HII regions in the Galaxy and using observations of the Galactic background in the H166α line found in literature, we investigated the strong inhomogeneity of the DIG in the direction of longitude 33.5° near the Galaxy plane, where objects located at close angular distances from each other have

    更新日期:2020-08-31
  • Solar System Encounters with Open Star Clusters
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    M. D. Sizova, S. V. Vereshchagin, B. M. Shustov, N. V. Chupina

    Abstract The time and minimum distances of approaches were calculated more than 100 open star clusters (OSCs) near the Solar System over the past 5 Myr. It was shown that the closest proximity of the centers of the OSCs to the Solar System usually exceeded 60 pc. The Hyades cluster approached the Solar System at ~25 pc. The effect of such encounters on the comet motion in the outer regions of the Oort

    更新日期:2020-08-31
  • Radio Emission of the Combined Supernova Remnant 3C396 (G39.2-0.3)
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    V. P. Ivanov, A. V. Ipatov, I. A. Rakhimov, T. S. Andreeva

    Abstract Using the RT-32 radio telescope of the “Svetloe” IAA RAS observatory in 2017–2018, the flux density measurements of the combined (composite) supernova remnant (SNR) 3С396 (G39.2-0.3) at frequencies of 4840 and 8450 MHz are presented. The data obtained demonstrate source variability. Published data were used to determine the 3C396 flux density in 1962–2008 based on a comparison of the intensities

    更新日期:2020-08-31
  • Variability of the Blazar B1308+326 in 2011–2018
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    V. A. Hagen-Thorn, D. A. Morozova, E. I. Hagen-Thorn, S. S. Savchenko, I. S. Troitsky, L. V. Shaliapina, E. V. Volkov

    Abstract— The monitoring results of the blazar B1308+326 in the optical and radio bands in 2011–2018 are presented and analyzed. An optical flare of the object associated with the passage of revealed superluminal components through the radio core, coinciding in time with a γ-ray outburst, as well as outbursts at 43 GHz, were detected. The photometric variability is explained by a variable component

    更新日期:2020-08-31
  • Quasi-Resonant States of Hydrogen Gas
    Astron. Rep. (IF 1.164) Pub Date : 2020-08-31
    V. P. Grinin, N. A. Katysheva, T. A. Ermolaeva, D. V. Dmitriev

    Abstract The article considers the poorly studied states of hydrogen gas (called here “quasi-resonant”) with anomalously high intensity ratios of the lines in the Balmer series, \(I({{{\text{H}}}_{\alpha }}){\text{/}}I({{{\text{H}}}_{\beta }})\). It is shown that such states arise in the case of large optical thicknesses of the emitting gas occurring at the frequencies of the Balmer lines, when the

    更新日期:2020-08-31
  • Multiperiodicity in the Orbital Period Variations of the Eclipsing Binary System Z Per
    Astron. Rep. (IF 1.164) Pub Date : 2020-07-17
    A. I. Khaliullina

    Abstract The variations in the orbital period of the eclipsing binary system Z Per have been analyzed. It has been shown that the variations in the period can be represented as a superposition of the secular decrease in the period at a rate of 1.61 × 10–6 days/year and its three cyclic variations with periods of 22.6, 37.9, and 62.4 years. Z Per is most likely a quadruple system with periods of additional

    更新日期:2020-07-17
  • Possible New Envelope Types of Hot Jupiters
    Astron. Rep. (IF 1.164) Pub Date : 2020-07-17
    A. G. Zhilkin, D. V. Bisikalo

    Abstract—For the case of the sub-Alfvén regime of the stellar wind flyby around the planet, the flow structure in the vicinity of a hot Jupiter have been studied by three-dimensional numerical simulation. As an example, the hot Jupiter HD 209458b was considered. The planet’s magnetic moment was set equal to 10% of the magnetic moment of Jupiter. The average magnetic field at the parent star’s surface

    更新日期:2020-07-17
  • Classification of Young Pulsars and Empirical Evolution of Regular Braking Index
    Astron. Rep. (IF 1.164) Pub Date : 2020-07-17
    A. P. Glushak

    Abstract—The distribution of young pulsars in the log(dP/dt)–log(tc) diagram that have a characteristic age tc < ~5 × 106 yr and a period derivative dP/dt > ~10–16 is analyzed. Six clusters-stripes are revealed for the first time, along which the long-term evolution tracks of individual pulsars pass. The mean track in a stripe corresponds to the long-term regular evolution for a typical pulsar of this

    更新日期:2020-07-17
  • Exoplanet Transients: Possible Variations in the Limb-Darkening Coefficients of Eclipsed Stars at Short Time Intervals
    Astron. Rep. (IF 1.164) Pub Date : 2020-07-17
    M. K. Abubekerov, N. Yu. Gostev

    Abstract The interpretation of high-precision transit light curves of binary systems with exoplanets Kepler-5b, Kepler-6b, and Kepler-7b is performed for three different epochs. It has been demonstrated that the values of the stellar limb-darkening coefficients differ significantly for each epoch, while the geometric parameters for each epoch agree well with each other within the error margin. It is

    更新日期:2020-07-17
  • Black Hole Shadow Observations with Space-Ground Interferometers
    Astron. Rep. (IF 1.164) Pub Date : 2020-07-17
    E. V. Mikheeva, S. V. Repin, V. N. Lukash

    Abstract The study explores black hole (BH) shadow images which can be restored by data processing and image recovery procedures during space Very Large Baseline Interferometry (VLBI) missions in the future. For Kerr BHs with masses and coordinates of SgrA*, M87*, and M31*, all illuminated by a light source behind them, three kinds of observation are considered: the ground-based interferometer (similar

    更新日期:2020-07-17
  • Evolution of OH and H 2 O Maser Emission in the Active Star Formation Region NGC 2071
    Astron. Rep. (IF 1.164) Pub Date : 2020-07-17
    N. T. Ashimbaeva, P. Colom, V. V. Krasnov, E. E. Lekht, M. I. Pashchenko, G. M. Rudnitskii, A. M. Tolmachev

    Abstract We present the observation results of the star forming region NGC 2071 in the 1.35-cm H2O line and 18-cm OH lines obtained with the 22-m radio telescope in Pushchino (Russia) and the large radio telescope in Nançay (France), respectively. The catalog of H2O maser emission spectra from December 2010 to January 2020 is given. The total flux variability for the entire monitoring period (1979–2020)

    更新日期:2020-07-17
  • Oxygen Atom Escape from the Martian Atmosphere during Proton Auroral Events
    Astron. Rep. (IF 1.164) Pub Date : 2020-07-17
    V. I. Shematovich, E. S. Kalinicheva

    Abstract We present the model calculation results of the atomic oxygen loss rate from the Martian atmosphere induced by precipitation of high-energy protons and hydrogen atoms (H/H+) from the solar wind plasma. Penetration of energetic protons and hydrogen atoms from the solar wind plasma to the upper atmosphere of Mars at altitudes of 100−250 km is accompanied by the momentum and energy transfer in

    更新日期:2020-07-17
  • On the Dark Matter Profile Mass Dependence
    Astron. Rep. (IF 1.164) Pub Date : 2020-07-17
    A. Del Popolo

    Abstract In this paper, we check the claim of dependence of the halo density profile on the ratio between stellar and halo mass. Namely, we want to continue the work done in a previous paper by Del Popolo (2015), to see to what extent the SN feedback scenario is able to describe the inner structure of galaxies, employing more sophisticated statistical tools than those indicated in the quoted paper

    更新日期:2020-07-17
  • Principles of Pulsar Space Navigation
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-16
    A. E. Rodin, V. V. Oreshko, V. A. Potapov, M. S. Pshirkov, M. V. Sazhin

    Abstract The paper considers the principles of space navigation using pulsars observed in the radio range. The requirements for receiving equipment are outlined, a recommended pulsar list is given, and an algorithm for determining the position of a spacecraft in barycentric coordinates and calculating corrections to the onboard time scale is described.

    更新日期:2020-06-16
  • Three-Dimensional Numerical Simulation of a Flow Structure in the Asynchronous Polar CD Ind in the Approximation of an Offset Dipole Magnetic Field of a White Dwarf
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-16
    A. V. Sobolev, A. G. Zhilkin, D. V. Bisikalo, D. A. H. Buckley

    The flow structure in the asynchronous polar CD Ind was investigated in the approximation of an offset dipole. Computation results made it possible to identify such system features as the drift of hot spots over the white dwarf surface, the flow structure dependence on the phase of the beat period, and the magnetic pole switching. To study the flow structure, a three-dimensional numerical MHD model

    更新日期:2020-06-16
  • Rapid Polarized Emission Variability of Blazar S5 0716+714 in Optical Range
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-16
    V. S. Bychkova, N. S. Kardashev, K. L. Maslennikov, V. L. Plokhotnichenko, G. M. Beskin, S. V. Karpov

    Abstract— The results of polarimetric observations of blazar S5 0716+714, carried out with the 6-meter BTA telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences, are presented. The polarized emission microvariability of blazar S5 0716+714 was observed in the R band with an initial time resolution of 3–5 seconds. Exposures were integrated at 1-minute intervals with a

    更新日期:2020-06-16
  • Restructuring of the Solar Magnetic Fields and Flare Activity Centers in Cycle 24
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-16
    A. V. Borovik, A. V. Mordvinov, E. M. Golubeva, A. A. Zhdanov

    Abstract The development of the solar magnetic activity in cycle 24 has been analyzed. It has been shown that the significant north–south asymmetry of magnetic activity was accompanied by the asynchronous reorganization of solar magnetic fields in the northern and southern hemispheres. The formation of unipolar magnetic regions after the decay of activity centers has been studied. The meridional transport

    更新日期:2020-06-16
  • Detection of Five New Pulsars with the BSA LPI Radio Telescope
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-16
    S. A. Tyul’bashev, M. A. Kitaeva, V. S. Tyul’bashev, V. M. Malofeev, G. E. Tyul’basheva

    Abstract During five years of daily observations, the search for new pulsars using the BSA LPI radio telescope in 96 spatial beams covering 17 000 square degrees was conducted. Five new pulsars were identified. Candidate pulsars were selected in summed power spectra. A noise generator was used to renormalize data and total the power spectra for individual directions correctly. As a result, the sensitivity

    更新日期:2020-06-16
  • Mutual Gravitational Energy of Gaussian Rings and the Problem of Perturbations in Celestial Mechanics
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-05
    B. P. Kondratyev, V. S. Kornoukhov

    Abstract A new approach to the study of long-period and secular perturbations in celestial mechanics is developed. In contrast to the traditional use of the apparatus of the perturbing Lagrange function, we rely on the mutual potential energy of elliptic Gaussian rings. This approach is important due to the fact that instead of averaging the expression for the perturbing Lagrange function obtained

    更新日期:2020-06-05
  • Relativistic Reductions in High-Precision Measurements of the Earth’s Global Gravity Field Using a Multipair Constellation
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-05
    V. K. Milyukov, I. Yu. Vlasov, M. V. Sazhin, O. S. Sazhina, V. N. Sementsov

    Abstract— The theory of relativistic reductions for future challenges of space gravimetry with target accuracy of up to 1 picometer is developed in this paper.

    更新日期:2020-06-05
  • Survey of Molecular Emission Lines in the WB 673 Interstellar Filament
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-05
    O. L. Ryabukhina, M. S. Kirsanova

    Abstract— We report observations of molecular line emission toward dense clumps of the WB 673 interstellar filament: WB 668, WB 673, S233–IR, and G173.57+2.43. The observations were done with the 20-m telescope at the Onsala Space Observatory (Sweden). Maps of emission, column densities, and relative abundances of CO, N2H\(^{ + }\), CS, HCN, and HNC molecules are presented. It was found that the molecular

    更新日期:2020-06-05
  • Narrow-Line SY1 NGC 4748 in X-Rays: Detailed Case-Study
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-05
    A. Vasylenko, E. Fedorova, A. Del Popolo

    Abstract We analyze all the available X-ray data in order to monitor the narrow-line Seyfert 1 galaxy NGC 4748, namely XMM-Newton (EPIC and OM), INTEGRAL (ISGRI and JEM-X), and SWIFT (BAT and XRT) data to study both the wide-band 0.5–195 keV spectrum and light curves in details. To this aim, we use the autocorrelation analysis of the light curves, modeling the spectra with several physically-conditioned

    更新日期:2020-06-05
  • Multifactorial Method of Search for Small Bodies in Close Orbits
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-05
    M. V. Sergienko, M. G. Sokolova, K. V. Kholshevnikov

    Abstract The results of the search for Apollo, Amor, and Aten asteroids with the orbits close to those of meteoroids of the δ-Cancrids meteor complex (code DCA), which consists of the northern (code NCC) and southern (code SCC) branches, are presented. The search for small bodies in close orbits was performed on the basis of a multifactorial method of combining several criteria: Drummond orbital similarity

    更新日期:2020-06-05
  • Orbital Decay in High-Mass X-Ray Binaries
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-05
    S. V. Chernov

    The variation of the orbital periods found in high-mass X-ray binaries occurring over time can be explained by two models. According to the first model, orbital decay occurs due to dynamic tidal forces. The second model shows that the change occurs due to the inertia moments of a massive star during its evolution. These models are applied to LMC X-4 and Cen X-3.

    更新日期:2020-06-05
  • Study of Bright Compact Radio Sources of the Northern Hemisphere at 111 MHz
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-05
    S. A. Tyul’bashev, I. V. Chashei, I. A. Subaev, M. A. Kitaeva

    Abstract The search for compact components of strong (\({{S}_{{{\text{int}}}}} \geqslant 5\) Jy at 102.5 MHz) discrete radio sources from the Pushchino catalogue was carried out using the method of interplanetary scintillation. A total of 3620 sources were examined, and 812 of them were found to harbor compact (scintillating) components. Estimates of fluctuations of the flux density of these compact

    更新日期:2020-06-05
  • Young Stellar Complexes in the Giant Galaxy UGC 11973
    Astron. Rep. (IF 1.164) Pub Date : 2020-06-05
    A. S. Gusev, F. Kh. Sakhibov, O. V. Ezhkova

    We present results of the analysis of photometric and spectroscopic observations of the young stellar complexes in the late giant spiral galaxy UGC 11973. Photometric analysis in the \(UBVRI\) bands have been carried out for the 13 largest complexes. For one of them, metallicity of the surrounding gas \(Z = 0.013 \pm 0.005\), the mass \(M = (4.6 \pm 1.6) \times {{10}^{6}}{\kern 1pt} {{M}_{ \odot }}\)

    更新日期:2020-06-05
  • BVI c Observations and Search for Evolutionary Variations in the Cepheid V811 Oph Period
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    L. N. Berdnikov, A. A. Belinskii, N. I. Shatskii, M. A. Burlak, N. P. Ikonnikova, E. O. Mishin, D. V. Cheryasov, S. V. Zhuiko

    Abstract For the first time, BVIc observations of the Cepheid V811 Oph were obtained by using a new 60‑cm telescope at the Caucasus Mountain Observatory, Sternberg Astronomical Institute, Moscow State University (SAI MSU). An \(O{-}C\) diagram covering a time span of 124 years was plotted using photometry from old photographic and modern sky surveys. The diagram has a parabola shape, which made it

    更新日期:2020-04-23
  • New Expansion Rate Estimate of the Scorpius–Centaurus Association Based on T Tauri Stars from the Gaia DR2 Catalog
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    V. V. Bobylev, A. T. Baykova

    Abstract The kinematic properties of the Scorpius–Centaurus association were studied using spatial velocities of approximately 700 young T Tauri stars. Their proper motions and trigonometric parallaxes were selected by Zari et al. from the Gaia DR2 catalog, and radial velocities were taken from various sources. The linear expansion coefficient’s new estimate of the association \(K = 39 \pm 2\) km/s/kpc

    更新日期:2020-04-23
  • Three- and Five-Minute Oscillations Modulated by Flares as a Means of Solar Atmosphere Sensing
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    A. A. Chelpanov, N. I. Kobanov

    Abstract— We applied a new approach to measure the time delays of magnetohydrodynamic waves propagating in the solar atmosphere. A small flare in the flare region of the chromosphere served as a modulator of 3‑ and 5-minute oscillations. The oscillation amplitude increased several times, which made it possible to easily fix the wave train formed as it spread upward through the solar atmosphere layers

    更新日期:2020-04-23
  • Norm of the Position Shift of a Celestial Body in a Dynamical Astronomy Problem
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    K. V. Kholshevnikov, N. Batmunkh, K. I. Oskina, V. B. Titov

    Abstract— The averaging method is widely used in celestial mechanics, in which a mean orbit is introduced and slightly deviates from an osculating one, as long as disturbing forces are small. The difference \(\delta {\mathbf{r}}\) in the celestial body positions in the mean and osculating orbits is a quasi-periodic function of time. Estimating the norm \(\left\| {\delta {\mathbf{r}}} \right\|\) for

    更新日期:2020-04-23
  • Dynamic Dark Energy Equation of State (EoS) and Hubble Constant Analysis Using Type Ia Supernovae from Union 2.1 Dataset
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    S. F. Rahman

    Abstract This paper constraints dynamic dark energy equation of state (EoS) parameters using the type Ia supernovae from Union 2.1 dataset. The paper also discusses the dependency of dynamic dark energy EoS parameters on the chosen or assumed value of the Hubble Constant. To understand the correlation between the Hubble Constant values and measured dynamic dark energy EoS parameters, we used recent

    更新日期:2020-04-23
  • Laser-Induced Dissociation of the Monolayer of Adsorbed Methanol Molecules
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    V. N. Varakin, M. S. Murga

    Abstract— Astronomical observations indicate a high abundance of methanol molecules in the gas phase of molecular-cloud dense cores, which cannot be explained by gas-phase chemical reactions only. A significant contribution to the methanol abundance should be provided by chemical reactions on the dust particle surface with subsequent desorption of the produced molecules into the gas phase. For the

    更新日期:2020-04-23
  • Galaxies with Declining Rotation Curves
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    D. I. Zobnina, A. V. Zasov

    Abstract A sample of 22 spiral galaxies compiled from published data is studied. The galaxy rotation curves pass through a maximum distance of more than ~1 kpc from the center with a subsequent decrease in the rotation velocity. The galaxy position in the Tully–Fisher (TF) and baryonic Tully–Fisher (BTF) diagrams show that the maximum rotation velocities are located on the same sequence with other

    更新日期:2020-04-23
  • Modeling of Spectroscopic and Interferometric Observations of the Herbig Star VV Ser with Hybrid Models
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    L. V. Tambovtseva, A. Kreplin, V. P. Grinin, G. Weigelt

    Abstract Modeling of hydrogen emission lines is a powerful tool to study physical processes in the nearest vicinity of young stars because spectral lines carry information on the kinematics and physical conditions of the gas. One of the lines that probe emitting regions closest to the star is the Br\(\gamma \) line. We consider different types of hybrid models to reproduce both interferometric VLTI-AMBER

    更新日期:2020-04-23
  • Monitoring of the Blazar J0238+1636 with the RATAN-600 and RT-32 in 2014−2019
    Astron. Rep. (IF 1.164) Pub Date : 2020-04-14
    M. A. Kharinov, V. K. Konnikova, A. V. Ipatov, I. A. Ipatova, A. K. Erkenov

    Abstract The presented observation results of the blazar J0238+1636 were obtained in: 2014–2019 with the RATAN-600 radio telescope from the Special Astrophysical Observatory of the Russian Academy of Sciences at 2.3, 4.8, 8.2, 11.2, and 21.7 GHz; and 2015–2017 with the 32-m Zelenchuk and Badary radio telescopes of the Institute of Applied Astronomy of the Russian Academy of Sciences at 4.84 and 8.57

    更新日期:2020-04-23
  • 3D Simulation of Anisotropic Heat Transfer in Outer Layers of Magnetized Neutron Stars
    Astron. Rep. (IF 1.164) Pub Date : 2020-03-31
    I. A. Kondratyev, S. G. Moiseenko, G. S. Bisnovatyi-Kogan, M. V. Glushikhina

    Abstract— The results of three-dimensional numerical simulation of heat transfer in the outer layers of magnetized neutron stars are presented. Determining the structure of the magnetic field on a neutron star surface is an important task of modern astrophysics. In the presence of strong magnetic fields, the medium becomes anisotropic, and the laws of heat conduction change. The tensor coefficient

    更新日期:2020-04-23
  • Eclipsing System PS UMa: Evolutionary Status and Physical Parameters of the Components
    Astron. Rep. (IF 1.164) Pub Date : 2020-03-31
    I. M. Volkov, A. S. Kravtsova

    Abstract We present the first high accuracy UBVRI(RI)c CCD light curves of the newly discovered eclipsing system PS UMa = GSC 4375 1733 (\(P = 9_{·}^{d}27\), \(V = 12_{·}^{m}42\)). The photometric solutions are found, the physical parameters of the components are derived. The eccentricity of the orbit was found to be negligible e = 0.074, which made it difficult to measure the rate of the apsidal rotation

    更新日期:2020-04-23
  • Failed Eruptions of Solar Filaments
    Astron. Rep. (IF 1.164) Pub Date : 2020-03-31
    B. P. Filippov

    Abstract Solar filaments (prominences), which suddenly and swiftly ascend, i.e., become eruptive, sometimes decelerate and stop at comparatively low altitudes. Causes of failed eruptions generally remain uncertain. The present study analyzes two eruptive phenomena with very similar initial geometries and configurations of external magnetic fields; one of these eruptions evolves in a coronal mass ejection

    更新日期:2020-04-23
  • Structure and Features of the Galactic Magnetic-Field Reversals Formation
    Astron. Rep. (IF 1.164) Pub Date : 2020-03-31
    R. R. Andreasyan, E. A. Mikhailov, H. R. Andreasyan

    Abstract At the present time, the induction of several microgauss in large-scale fields of the Galaxy has been repeatedly confirmed. There are numerous arguments in favor of the fact that the magnetic field exhibits so-called reversals associated with a direction change from one region to another. Such configurations are allowed in the nonlinear equations context of the dynamo theory, which describes

    更新日期:2020-04-23
  • The Orientation Influence of a Hot Jupiter’s Intrinsic Dipole Magnetic Field on the Flow Structure in Its Extended Envelope
    Astron. Rep. (IF 1.164) Pub Date : 2020-03-31
    A. G. Zhilkin, D. V. Bisikalo, P. V. Kaygorodov

    Abstract The orientation parameter effect of a hot Jupiter’s intrinsic dipole magnetic field on the flow structure in an extended gaseous (ionospheric) envelope of the planet is studied with a three-dimensional numerical simulation. For example, the hot Jupiter HD 209458b is considered. The magnitude of the planet’s magnetic momentum was set equal to 0.1 of the magnetic momentum of Jupiter. The parameters

    更新日期:2020-04-23
  • A Survey of High Mass Star Forming Regions in the Lines of Deuterated Molecules
    Astron. Rep. (IF 1.164) Pub Date : 2020-03-31
    E. A. Trofimova, I. I. Zinchenko, P. M. Zemlyanukha, M. Thomasson

    Abstract A survey of massive star forming regions in the lines of the lowest transitions of deuterated molecules DCN, DNC, DCO+, N2D+ in the 4 mm wavelength range was performed using the 20 m radio telescope of the Onsala Space Observatory. A total of about 60 sources was observed. Lines of the DCN, DNC, and DCO+ molecules are registered in about a third of them, lines of the N2D+ molecule only in

    更新日期:2020-04-23
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