Astrophysical Bulletin最新文献

{"title":"Structure of Magnetic Fields of Primary Components of Close Binary Systems BD(-)19 5044L, HD 37017, HD 98088","authors":"Yu. V. Glagolevskij","doi":"10.1134/S1990341325600425","DOIUrl":"10.1134/S1990341325600425","url":null,"abstract":"<p>The magnetic field structures of the primary components in three\u0000close binary systems have been studied. In all their properties,\u0000they do not differ from single magnetic stars. There are signs\u0000that the rotational momentum is lost in two ways: 1) it is\u0000transferred to the clouds surrounding the magnetic protostar along\u0000the field lines and 2) through tidal interactions with a close\u0000component. Within the hypothesis of the fossil origin of magnetic\u0000stars, a possible scheme for the formation of close binary systems\u0000with a magnetic companion has been considered.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"418 - 427"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Orbital Dynamics of Globular Clusters in the Central Region of the Milky Way","authors":"A. T. Bajkova,&nbsp;A. A. Smirnov,&nbsp;V. V. Bobylev","doi":"10.1134/S1990341325600310","DOIUrl":"10.1134/S1990341325600310","url":null,"abstract":"<p>The regularity/chaoticity of orbits of 45 globular clusters in the\u0000central region of the Galaxy with a radius of 3.5 kpc, which are\u0000subject to the greatest influence of the elongated rotating bar,\u0000is analyzed. Various methods of analysis are used, namely, the\u0000methods of calculating the maximum characteristic Lyapunov\u0000exponents (MCLE), MEGNO (Mean Exponential Growth factor of Nearby\u0000Orbits), the Poincaré section method, the frequency method based\u0000on calculating fundamental frequencies, and a new method is\u0000proposed based on calculating the orbit amplitude spectrum as a\u0000function of time and calculating the entropy of the amplitude\u0000spectrum as a measure of orbital chaos. Bimodality is found in the\u0000histogram of the distribution of positive Lyapunov exponents\u0000calculated in the classical version, without renormalizing the\u0000shadow orbit, which allows implementing a probabilistic method for\u0000GC classification, which is also a new approach. To construct the\u0000orbits of globular clusters, we used the gravitational potential\u0000model with a bar in the form of a triaxial ellipsoid. The\u0000following bar parameters were adopted: mass <span>(10^{10} M_{odot})</span>,\u0000length of the semi-major axis 5 kpc, angle of rotation of the bar\u0000axis 25<span>({}^{circ})</span>, rotation velocity 40 km s<span>({}^{-1})</span> kpc<span>({}^{-1})</span>. To\u0000form the 6D phase space required for integrating the orbits, we\u0000used the most accurate astrometric data to date from the Gaia\u0000satellite (EDR3), as well as new refined average distances to\u0000globular clusters. Globular clusters with regular and chaotic\u0000dynamics were classified. As the analysis showed, globular\u0000clusters with small pericentric distances and large eccentricities\u0000are most susceptible to the influence of the bar and demonstrate\u0000the greatest chaos. It is shown that the results of the\u0000classification of globular clusters by the nature of their orbital\u0000dynamics, obtained using the various analysis methods considered\u0000in the work, correlate well with each other.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"369 - 393"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of Absorption by (boldsymbol{Q})-Method for (boldsymbol{JHK}) Photometry in Embedded Clusters","authors":"T. A. Permyakova","doi":"10.1134/S1990341325600346","DOIUrl":"10.1134/S1990341325600346","url":null,"abstract":"<p>In this paper, we describe the absorption determination with the\u0000<span>(Q)</span>-method for the 2MASS photometry (<span>(J)</span>, <span>(H)</span>, and <span>(K_{S})</span> bands).\u0000Using the Pleiades and Praesepe stars, we determine the\u0000zero-reddening sequence for different values of the color excess\u0000ratios <span>(E(J-H)/E(H-K_{S}))</span>. In this paper, we consider a sequence\u0000consisting of two segments, that leads to an uncertainty in the\u0000determining of absorption—one value of the <span>(Q)</span> parameter\u0000corresponds to two values of the non-reddened color index. We\u0000propose a method to select a segment of the zero-reddening\u0000sequence for the main sequence stars of the cluster. The method is\u0000based on the difference in the position of stars of different\u0000segments in the cluster luminosity function. To test the proposed\u0000method, we simulate the luminosity functions of clusters with the\u0000non-uniform absorption distribution in the cluster region. With\u0000the typical absorption values in embedded clusters, about 10<span>(%)</span>\u0000of stars are erroneously assigned, but in some cases this fraction\u0000can reach 20<span>(%)</span>. Thus, despite the fact that irregular absorption\u0000distorts the distribution of stars of different segments on the\u0000cluster luminosity function, our method allows one to separate\u0000stars with an error of no more than 20<span>(%)</span>.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"394 - 406"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic Fields of Chemically Peculiar Star in Clusters Trumpler 37, NGC 2281, and Melotte 111","authors":"I. I. Romanyuk,&nbsp;A. V. Moiseeva,&nbsp;E. P. Korchagina,&nbsp;I. A. Yakunin,&nbsp;V. N. Aitov","doi":"10.1134/S1990341325600413","DOIUrl":"10.1134/S1990341325600413","url":null,"abstract":"<p>We continue to search for and analyze magnetic fields of\u0000chemically peculiar stars in open clusters of different ages. The\u0000paper presents the analysis of the star clusters Trumpler 37,\u0000NGC 2281, and Melotte 111. The observed data were obtained using\u0000the Main Stellar Spectrograph mounted on the 6-m telescope of\u0000SAO RAS. No CP stars were found in the Trumpler 37 cluster: all\u0000six candidates turned out to be non-magnetic stars with strong\u0000emission lines in their spectra. In NGC 2281, we observed only two\u0000stars, HD 49040 and HD 49363. Several magnetic stars with weak\u0000fields were discovered in the Melotte 111 cluster. As a result, we\u0000did not find stars with a strong (more than 1 kG) longitudinal\u0000magnetic field in any of the studied clusters.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"407 - 417"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gas-phase and Surface Chemistry\u0000in the Massive Star-Forming Region RCW 120","authors":"K. V. Plakitina,&nbsp;M. S. Kirsanova,&nbsp;D. S. Wiebe,&nbsp;O. V. Kochina","doi":"10.1134/S1990341325600073","DOIUrl":"10.1134/S1990341325600073","url":null,"abstract":"<p>Molecules in the interstellar medium form both in the gas phase\u0000and on dust particles. The chemical pathways for molecular\u0000formation are not yet well understood in detail, so the question\u0000of which pathway predominates for a particular molecule remains\u0000open. We analysed broadband emission spectra of a dense molecular\u0000clump in the RCW120 region, obtained with the APEX telescope in\u0000the 200–260 GHz range, to investigate molecular formation\u0000pathways in regions of massive star formation at an early\u0000evolutionary stage. The correlations between the derived molecular\u0000column densities, obtained under the LTE assumption, were\u0000investigated. An excess of methanol was found in the southern part\u0000of the dense clump compared to its northern part, while the\u0000abundance of other molecules, such as CH<span>({}_{3})</span>CN and CH<span>({}_{3})</span>CCH,\u0000remain comparable. The methanol abundance is also elevated\u0000relative to other oxygen-bearing molecules, such as OCS and SO. To\u0000identify possible causes of the enhanced methanol abundance in the\u0000southern part of the clump, we conducted simulations using the\u0000astrochemical model <span>Presta</span> in a two-phase approximation,\u0000accounting for chemical processes in both the gas phase and the\u0000mantles of dust grains. Modeling showed that the enhanced methanol\u0000abundance in the gas phase may be due to its photodesorption from\u0000icy mantles. At an <span>(A_{V})</span> value between <span>(4^{textrm{m}})</span> and\u0000<span>(6^{textrm{m}})</span>, methanol efficiently desorbs from ice mantles of\u0000dust grains upon interaction with photons, but it is not yet\u0000destroyed by UV radiation in the gas phase. A strong linear\u0000correlation between molecular column densities indicates that\u0000these molecules form in the same phase—either in the gas phase\u0000or on dust. However, integrated intensity maps of these molecules\u0000may differ, as seen for CCH and CH<span>({}_{3})</span>CN. If molecules form in\u0000different phases—one in the gas phase and the other in dust\u0000mantles—no correlation is observed, as in the case of CCH and\u0000CH<span>({}_{3})</span>OH. The weak correlation between methanol and oxygen-bearing\u0000molecules that form on dust suggests that only the upper part of\u0000the dust mantles, rich in CO ice, is being destroyed in the\u0000southern part of the clump.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"348 - 368"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SINIS Detectors in the Subterahertz Range as a Basis for a Receiver for Radio Astronomical Research with the SAO RAS Optical Big Telescope Alt-Azimuth","authors":"M. A. Tarasov,&nbsp;A. A. Gunbina,&nbsp;A. M. Chekushkin,&nbsp;M. A. Markina,&nbsp;R. A. Yusupov,&nbsp;M. Yu. Fominskii,&nbsp;L. V. Filippenko,&nbsp;V. S. Edelman,&nbsp;V. F. Vdovin,&nbsp;V. A. Stolyarov,&nbsp;I. I. Zinchenko,&nbsp;A. M. Krasilnikov,&nbsp;A. S. Marukhno,&nbsp;M. A. Mansfeld,&nbsp;D. E. Kukushkin,&nbsp;D. A. Sazonenko,&nbsp;O. S. Bolshakov,&nbsp;A. B. Ermakov,&nbsp;I. V. Lesnov,&nbsp;A. F. Valeev","doi":"10.1134/S1990341324600996","DOIUrl":"10.1134/S1990341324600996","url":null,"abstract":"<p>There is an ongoing need in ground-based astronomy for\u0000ultra-sensitive receivers, both coherent (e.g., superheterodyne)\u0000and incoherent types, the latter offering potentially higher\u0000sensitivity. Both types rely on superconducting or cryogenically\u0000cooled semiconductor materials. This study explores the\u0000feasibility of using SINIS-based\u0000(Superconductor–Insulator–Normal\u0000metal–Insulator–Superconductor) detectors as incoherent\u0000superconducting receivers. We evaluate the ultimate performance\u0000parameters of SINIS detectors depending on the choice of\u0000superconducting material, operating temperature, and detection\u0000regime. Under moderate sub-Kelvin cooling (down to <span>(0.28)</span> K),\u0000aluminum-based SINIS detectors may achieve a responsivity of up to\u0000<span>(10^{8})</span> V W<span>({}^{-1})</span> and a noise-equivalent power\u0000<span>(text{NEP}=10^{-17})</span> W Hz<span>({}^{-1/2})</span>. For niobium-based SINIS\u0000detectors operating at 4.2 K, our estimates yield an\u0000<span>(text{NEP}=1.6times 10^{-16})</span> W Hz<span>({}^{-1/2})</span>, which may be of\u0000practical interest for specific applications. At the Special\u0000Astrophysical Observatory of the Russian Academy of Sciences (SAO\u0000RAS), a prototype project is underway to develop a domestic\u0000subterahertz observatory module integrated with the Big Telescope\u0000Alt-azimuthal (BTA). Within this framework, a SINIS-based\u0000subterahertz receiver is planned to be installed at the Nasmyth\u0000focus of the BTA optical telescope. This paper provides a\u0000technical overview and proposed design of the SINIS receiver,\u0000taking into account the optical telescope’s reflective system\u0000architecture, its immediate environment, and the expected\u0000scientific goals of such an observational setup.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"502 - 518"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic Fields of Chemically Peculiar and Related Stars. XI. Main Results Obtained in 2024 and Analysis of Immediate Prospects","authors":"I. I. Romanyuk,&nbsp;A. V. Moiseeva","doi":"10.1134/S199034132560036X","DOIUrl":"10.1134/S199034132560036X","url":null,"abstract":"<p>This paper presents a review of 67 scientific publications from\u00002024 devoted to stellar magnetism and related topics. The primary\u0000focus of recent research lies in the discovery of new magnetic\u0000stars and the monitoring of magnetic fields in chemically peculiar\u0000(CP) stars and other stellar types. Interest in the study of\u0000magnetic star emission in the X-ray and radio domains has also\u0000increased. The most significant new data were obtained using Gaia\u0000astrometry, TESS and Kepler photometry, and LAMOST low-resolution\u0000spectroscopy. The first results from the new SPIRou and CRIRES+\u0000spectrographs are also discussed.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"468 - 478"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Voluntary and Involuntary Technosignatures: Which Are to Be Encountered First","authors":"E. Haliki","doi":"10.1134/S1990341324600066","DOIUrl":"10.1134/S1990341324600066","url":null,"abstract":"<p>Numerous methods have been tried and many more are currently being\u0000attempted to discover technosignatures of intelligent\u0000civilizations. One thing is for sure: an existing technosignature\u0000would modify its environment in detectable ways. The current study\u0000has investigated all possible voluntary and involuntary\u0000technosignatures, ranging from beacons to Dyson megastructures and\u0000from self-replicating probes to the still hypothetical stellar\u0000engines, in order to determine the extent to which these\u0000technosignatures would reveal themselves within a specified finite\u0000sphere 500 light years across, corresponding to nearly half the\u0000average thickness of our Galaxy. We then estimated the\u0000probabilities of detection of such technosignatures based on the\u0000regions, or domains, they would produce and investigated whether\u0000or not a correlation exists with the position of civilizations on\u0000the Kardashev scale. The study further explored which ones of the\u0000voluntary and involuntary technosignatures have higher detection\u0000probabilities.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"488 - 501"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studing the Evolution of Strongly Magnetized White Dwarfs. III. Frequency of Occurence Depending on Age","authors":"V. N. Aitov,&nbsp;G. G. Valyavin","doi":"10.1134/S1990341325600401","DOIUrl":"10.1134/S1990341325600401","url":null,"abstract":"<p>The results of the latest study of the thermal evolution features\u0000of white dwarfs with large surface magnetic fields are presented.\u0000The main objective of the work is to test the hypothesis that for\u0000cooling degenerate stars—white dwarfs (WD)—the stopping of\u0000external convection by a magnetic field greater than one megagauss\u0000significantly slows down their cooling. For this purpose, the\u0000observed luminosity function of WDs with surface fields greater\u0000than one megagauss is constructed in a volume with a 20 pc radius\u000020 pc and compared to the known similar luminosity function of all\u0000WDs, regardless of their magnetic field values. The general\u0000tendency—a significant increase in the frequency of occurrence\u0000of magnetic white dwarfs (MWDs) with an increase in their absolute\u0000bolometric magnitude (a decrease in brightness) is confirmed.\u0000Empirical modeling of the effect of magnetically induced\u0000suppression of convection on the luminosity function of strongly\u0000magnetized WDs also showed an increase in their frequency with\u0000age, although with a shift of one stellar magnitude toward weaker\u0000magnitudes. This shift is a consequence of the imperfection of the\u0000model. The effect of an increase in the frequency of occurrence of\u0000strongly magnetized WDs with age cannot be explained either by a\u0000systematic difference in the masses of magnetic and non-magnetic\u0000(with magnetic fields below the detection limit) WDs, or by the\u0000peculiarities of their formation rates in different epochs.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"449 - 455"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Robophot: 60-cm Robotic Telescope of Kourovka Astronomical Observatory, URFU","authors":"N. A. Chazov,&nbsp;D. D. Tereshin,&nbsp;V. V. Krushinsky,&nbsp;A. A. Popov,&nbsp;A. O. Zemlina","doi":"10.1134/S1990341325600395","DOIUrl":"10.1134/S1990341325600395","url":null,"abstract":"<p>We present the results of the development and commissioning of the\u000060-cm RoboPhot telescope at the Kourovka Astronomical Observatory\u0000equipped with the TRIP three-channel photometer (Three-channel\u0000RoboPhot Imaging Photometer). The photometer is designed for\u0000simultaneous imaging in three bands of the SDSS photometric\u0000system: <span>(g)</span>, <span>(r)</span>, and <span>(i)</span>. Currently, it is equipped with only two\u0000CCD cameras with a resolution of <span>(2048times 2048)</span> pixels, a field\u0000of view of <span>(22^{prime}times 22^{prime})</span>, and an image scale of\u0000<span>(0overset{primeprime}{.}65)</span> pixel<span>({}^{-1})</span>. The primary\u0000objective of the telescope is high-precision multicolor\u0000differential photometry of asteroids and variable stars,\u0000particularly exoplanet transits. For stars with a magnitude of\u0000<span>(13overset{textrm{m}}{.}5)</span>, a differential photometry precision\u0000(rms) of 2.5 ppt in magnitudes is achieved with a\u0000120<span>({}^{textrm{s}})</span> exposure. The telescope is expected to become\u0000the leading instrument at the Kourovka Observatory for exoplanet\u0000studies and contribute to the TESS research program.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"80 3","pages":"479 - 487"},"PeriodicalIF":1.4,"publicationDate":"2025-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}