Changes in the Period of Negative Superhumps of Type SU UMa Dwarf Novae. II. NY Her (2017 and 2020)     

Pavlenko  E. P.  Sosnovskii  A. A.  Antonyuk  K. A.  Antonyuk  O. I.  Pit’  N. V.  Kokhirova  G. I.  Rakhmatullaeva  F. J.  Baklanov  A. V. 《Astrophysics》2021,64(3):293-305

Astrophysics - Photometric studies of the type SU UMa dwarf nova NY Her were made during 2017 and 2020 at the Crimean Astrophysical Observatory and at the Sanglokh Observatory over a total of 77...  相似文献   

Constructing a Stäckel Model of the Galaxy: Solving the Problem of Whether the Vertical Density Distribution Is Realistic     

Gromov  A. O.  Nikiforov  I. I. 《Astronomy Letters》2021,47(6):357-376

Astronomy Letters - Techniques for solving the problem of constructing a Stäckel model by generalizing the potential from the equatorial plane to the entire space are considered. The initial...  相似文献   

Spectroscopic Redshift Determination for a Sample of Distant Quasars Detected by the SRG Observatory Based on RTT-150 Observations. II     

Bikmaev  I. F.  Irtuganov  E. N.  Nikolaeva  E. A.  Sakhibullin  N. A.  Gumerov  R. I.  Sklyanov  A. S.  Glushkov  M. V.  Khamitov  I. M.  Borisov  V. D.  Burenin  R. A.  Zaznobin  I. A.  Krivonos  R. A.  Lyapin  A. R.  Medvedev  P. S.  Meshcheryakov  A. V.  Sazonov  S. Yu.  Sunyaev  R. A.  Khorunzhev  G. A.  Gilfanov  M. R. 《Astronomy Letters》2021,47(5):277-290

Astronomy Letters - Results of the spectroscopic observations at the 1.5-m Russian–Turkish telescope for another group of 12 X-ray sources discovered by the eROSITA telescope onboard the SRG...  相似文献   

Transient AT2018cow: A Scenario with an Equatorial Disk     

Urvachev  E. M.  Blinnikov  S. I.  Nomoto  K. 《Astronomy Letters》2021,47(11):738-745

Astronomy Letters - To explain the presence of early X-ray emission from the object AT2018cow, we have studied a scenario with the presence of dense ejecta in the system in the equatorial plane....  相似文献   

Spectroscopic Redshift Measurements for Galaxy Clusters from the Lockman Hole Survey with the eROSITA Telescope Onboard the SRG Observatory     

Zaznobin  I. A.  Burenin  R. A.  Lyapin  A. R.  Khorunzhev  G. A.  Afanasiev  V. L.  Grokhovskaya  A. A.  Dodonov  S. N.  Eselevich  M. V.  Uklein  R. I.  Bikmaev  I. F.  Khamitov  I. M.  Gilfanov  M. R.  Lyskova  N. S.  Medvedev  P. S.  Sunyaev  R. A. 《Astronomy Letters》2021,47(3):141-149

Astronomy Letters - We present the first results of our program of optical observations for galaxy clusters from the Lockman Hole X-ray survey with the eROSITA telescope onboard the SRG space...  相似文献   

The additional radiation of Cyg X-1 at primary minimum     

I. Voloshina  V. M. Lyuty 《Astronomische Nachrichten》1995,316(2):85-90

New UBV-photoelectric observations of the well-known massive X-ray binary system Cyg X-1/V 1357 Cyg are obtained near the primary minimum. The detailed analysis of these observations confirms the existence of additional blue radiation which appears as a narrow peak with an amplitude of 0.01–0.02 mag near phase 0.00 on the light curve (the superior conjunction of the relativistic component), firstly detected by Lyuty (1985). This emission does not appear at every orbital cycle. The appearance of this narrow peak of additional blue radiation on the light curve of Cyg X-1 can be explained as the radiation of relativistic electrons in the disturbed magnetic field of the optical star in frames of the model proposed by Ikhsanov and Fabrika (1990).  相似文献   

Photoelectric observations in a wide-field area around the Praesepe cluster     

K. N. Grankin  M. A. Ibragimov  I. E. Tselishchev 《Astronomische Nachrichten》1995,316(3):159-162

The PPM catalogue numbers, photoelectric magnitudes V, color-indexes U – B, B – V, V – R and rms errors of their determinations for 51 stars of the secondary wide-angle photoelectric standard are published. The catalogue accuracy of quantities mentioned above is 0.007, 0.015, 0.006, 0.006 mag, respectively. A list of ten stars which are probably variable is published.  相似文献   

Photo—gravitational effects in the two—body problem     

I. Todoran  R. Roman 《Astronomische Nachrichten》1993,314(1):35-38

The effect of the radiation-pressure in the problem of the two bodies is analysed. It is found that such an effect is the same as that of reducing the stellar mass, m, by the factor p (0 ≤ p ≤ 1). The case p < 0 leads to stellar instability and, consequently, it is not considered here. The problem of the mass determination from spectroscopic observations is reviewed and an iterative method is recommended.  相似文献   

Implementation of the Concept for Creating a Spacecraft Double-Launch System as a Part of the Upper Stages of the Fregat Family     

Ishin  S. V.  Vikulenkov  V. P.  Fedoskin  D. I.  Poreshnev  A. Yu.  Jumahanov  N. B.  Yakovlev  B. D. 《Solar System Research》2020,54(7):690-698

Solar System Research - Abstract—Results of the implementation of a single concept for the development of the double launch system (SDZ) are presented, in particular the SDZ-La5 for the...  相似文献   

Optical Spectroscopy of SRG/eROSITA Objects with 2.5-m Telescope at the Caucasus Mountain Observatory of the SAI MSU     

Dodin  A. V.  Potanin  S. A.  Shatsky  N. I.  Belinski  A. A.  Atapin  K. E.  Burlak  M. A.  Egorov  O. V.  Tatarnikov  A. M.  Postnov  K. A.  Belvedersky  M. I.  Burenin  R. A.  Gilfanov  M. R.  Medvedev  P. S.  Meshcheryakov  A. V.  Sazonov  S. Yu.  Khorunzhev  G. A.  Sunyaev  R. A. 《Astronomy Letters》2020,46(7):429-438

Astronomy Letters - Based on observations with the new transient double-beam spectrograph (TDS) at the 2.5-m telescope of the Caucasus Mountain Observatory of SAI MSU, we have determined the types...  相似文献