Search Publications
New Active Galactic Nuclei Detected by the ART-XC and eROSITA Telescopes during the First Five SRG All-Sky X-ray Surveys
Gilfanov, M. R.; Medvedev, P. S.; Sunyaev, R. A. +8 more
We present the results of our identification of 14 X-ray sources detected in the eastern Galactic sky ($0^{\circ}<l<180^{\circ}$) in the 4-12 keV energy band on the combined map of the first five all-sky surveys (from December 2019 to March 2022) with the Mikhail Pavlinsky ART-XC telescope onboard the SRG observatory. All 14 sources are reli…
Determination of the Spiral Pattern Speed in the Galaxy from Three Samples of Stars
Bobylev, V. V.; Bajkova, A. T.
We invoke the estimates of the amplitudes of the velocity perturbations $fR$ and $f_{θ}$ caused by the influence of a spiral density wave that have been obtained by us previously from three stellar samples. These include Galactic masers with measured VLBI trigonometric parallaxes and proper motions, OB2 stars, and Cepheids. From these d…
Search for AGNs in Dwarf Galaxies in the the M81 Field with INTEGRAL Data
Sazonov, S. Yu.; Karachentsev, I. D.; Mereminskiy, I. A. +1 more
Using long-term INTEGRAL hard X-ray observations, we have put upper limits on the bolometric luminosity ($L_{\textrm{bol}}\lesssim 10^{41}$ erg s${}^{-1}$) of the nuclei of 72 nearby dwarf galaxies located in the M81 field. This has allowed us to constrain the fraction of galaxies in which the central black hole accretes matter at a rate above 0.1…
SRG/ART-XC Galactic Plane Survey near Galactic Longitude L 20°: Catalog of Sources
Sazonov, S. Yu.; Lutovinov, A. A.; Karasev, D. I. +11 more
We present a catalog of sources detected by the Mikhail Pavlinsky ART-XC telescope onboard the SRG space observatory during the observations of the Galactic plane region near a longitude l~20° (L20 field) in October 2019. The L20 field was observed four times in the scanning mode, which provided a uniform coverage of the sky region with a total ar…
Chromatic Afterglow of GRB 200829A
Minaev, P. Yu.; Pozanenko, A. S.; Volnova, A. A. +16 more
We present the results of our analysis of multiwavelength observations for the long gamma-ray burst GRB 200829A. The burst redshift $z≈ 1.29± 0.04$ has been determined photometrically at the afterglow phase. In gamma rays the event is one of the brightest (in isotropic equivalent), $E_{\textrm{iso}}\gtrsim 10^{54}$ erg. The multicolor light curve …
X-ray Properties of the Luminous Quasar PG 1634+706 at z=1.337 from SRG and XMM-Newton Data
Gilfanov, M. R.; Sunyaev, R. A.; Sazonov, S. Yu. +2 more
In the fall of 2019, during the in-flight calibration phase of the SRG observatory, the onboard eROSITA and Mikhail Pavlinsky ART-XC telescopes carried out a series of observations of PG 1634+706 — one of the most luminous (an X-ray luminosity ${∼}10^{46}$ erg s${}^{-1}$) quasars in the Universe at $z<2$. Approximately at the same dates this qu…
Determination of the Parameters of a Nonlinear Kinematic Galactic Rotation Model Based on the Proper Motions and Radial Velocities of Stars from the Gaia DR3 Catalogue
Tsvetkov, A. S.; Amosov, F. A.
We have solved the Ogorodnikov-Milne stellar-kinematics equations in the Galactic rectangular coordinate system based on the total velocities for a special sample of stars with radial velocities from the final Gaia Data Release 3 catalogue. We have found the region of applicability of the linear model and the regions that it describes poorly. We h…
Parameters of the Radcliffe Wave from Masers, Radio Stars, and T Tauri Stars
Bobylev, V. V.; Bajkova, A. T.; Mishurov, Yu. N.
The Radcliffe wave is shown to be present in both positions and vertical velocities of masers and radio stars belonging to the Local Arm. At the same time, it appears that the Radcliffe structure is not a wave in the true sense of the word. It more closely resembles a local high-amplitude spike that rapidly tails off. This structure has the larges…
Scandium Abundance in F-G-K Stars in a Wide Metallicity Range
Mashonkina, L. I.; Romanovskaya, A. M.
A new Sc II model atom has been constructed using up-to-date atomic data. To test it, we have carried out nonlocal thermodynamic equilibrium (non-LTE) calculations for three stars with reliably determined atmospheric parameters: the Sun, HD 61421 (Procyon), and HD 84937. Allowance for the departures from LTE leads to a decrease in the root-mean-sq…
Parameters of the Galactic Spiral Density Wave from Masers with Parallax Errors Less Than 10\boldsymbol{%}
Bobylev, V. V.; Bajkova, A. T.
We have studied the kinematics of Galactic masers and radio stars with measured VLBI trigonometric parallaxes and proper motions. We have considered masers with relative trigonometric parallax errors less than 10${%}$ and determined the Galactic rotation parameters from them. In particular, the linear rotation velocity of the Galaxy at the solar d…