Astrophysical Bulletin最新文献

{"title":"Radio Properties of High-Redshift Galaxies at (boldsymbol{zgeq 1})","authors":"M. L. Khabibullina,&nbsp;A. G. Mikhailov,&nbsp;Yu. V. Sotnikova,&nbsp;T. V. Mufakharov,&nbsp;M. G. Mingaliev,&nbsp;A. A. Kudryashova,&nbsp;N. N. Bursov,&nbsp;V. A. Stolyarov,&nbsp;R. Y. Udovitskiy","doi":"10.1134/S1990341323700190","DOIUrl":"10.1134/S1990341323700190","url":null,"abstract":"<p>Study of high-redshift radio galaxies (HzRGs) can shed light on the active galactic nuclei (AGNs) evolution in massive elliptical galaxies. The vast majority of observed high-redshift AGNs are quasars, and there are very few radio galaxies at redshifts <span>(z&gt;3)</span>. We present the radio properties of 173 sources optically identified with radio galaxies at <span>(zgeq 1)</span> with flux densities <span>(S_{1.4}geq 20)</span> mJy. Literature data were collected for compilation of broadband radio spectra, estimation of radio variability, radio luminosity, and radio loudness. Almost 60<span>(%)</span> of the galaxies have steep or ultra-steep radio spectra; 22<span>(%)</span> have flat, inverted, upturn, and complex spectral shapes, and 18<span>(%)</span> have peaked spectra (PS). The majority of the PS sources in the sample (20/31) are megahertz-peaked spectrum source candidates, i.e. possibly very young and compact radio galaxies. The median values of the variability indices at 11 and 5 GHz are <span>(V_{S_{11}}=0.14)</span> and <span>(V_{S_{5}}=0.13)</span>, which generally indicates a weak or moderate character of the long-term variability of the studied galaxies. The typical radio luminosity and radio loudness are <span>(L_{5}=10^{43}{-}10^{44})</span> erg s<span>({}^{-1})</span> and <span>(log R=3{-}4)</span> respectively. We have found less prominent features of the bright compact radio cores in our sample compared to high-redshift quasars at <span>(zgeq 3)</span>. The variety of the obtained radio properties shows the different conditions for the formation of radio emission sources in galaxies.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 4","pages":"443 - 463"},"PeriodicalIF":1.3,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140019324","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":"RFI-Resistant Decimeter Band Radiometer for the RATAN-600 Radio Telescope","authors":"A. M. Ripak,&nbsp;V. M. Bogod,&nbsp;S. A. Grenkov,&nbsp;M. K. Lebedev","doi":"10.1134/S1990341323600291","DOIUrl":"10.1134/S1990341323600291","url":null,"abstract":"<p>The development of methods for the radio frequency interference mitigation becomes a fundamental challenge for any radio astronomy research. In this paper, we report on the development and creation of a new spectrometer designed for solar observations at the RATAN-600 radio telescope, capable of excising radio interference using a statistical algorithm based on the spectral kurtosis estimation. The implementation of the external analog interface and the operation of the digital signal processing system based on the FPGA are described. The maximum spectral resolution reached is 122 kHz in the frequency band of 1.0–3.0 GHz. The output spectrum has from 64 to 8192 frequency bins, depending on the requirements of the observer, the output rate is 120 spectra per second. The test results and the first observations of the Sun show that the research method can successfully detect and suppress interference from most of the local radio interference sources.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 4","pages":"622 - 634"},"PeriodicalIF":1.3,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140019245","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":"The Influence of the Bar on the Dynamics of Globular Clusters in the Central Region of the Milky Way. Frequency Analysis of Orbits According to Gaia EDR3 Data","authors":"A. T. Bajkova,&nbsp;A. A. Smirnov,&nbsp;V. V. Bobylev","doi":"10.1134/S199034132360028X","DOIUrl":"10.1134/S199034132360028X","url":null,"abstract":"<p>This work is devoted to studying the influence of the bar on the orbital dynamics of globular clusters. The orbits of 45 globular clusters in the central galactic region with a radius of 3.5 kpc were analyzed using spectral dynamics methods in order to identify objects captured by the bar. To form the 6D phase space required for orbit integration, the most accurate astrometric data to date from the Gaia satellite (EDR3), as well as new refined average distances to globular clusters, were used. Since the parameters of the Milky Way bar are known with very great uncertainty, the orbits were constructed and their frequency analysis was carried out by varying the mass, length and angular velocity of rotation of the bar in a wide range of values with a fairly small step. The integration of orbits was carried out at 2.5 billion years ago. As a result, bar-supporting globular clusters were identified for each set of bar parameters. For the first time, an analytical expression has been obtained for the dependence of the dominant frequency <span>(f_{X})</span> on the angular velocity of rotation of the bar. In addition, the probabilities of globular clusters being captured by the bar were determined when the bar parameters were varied in certain ranges of values according to a random distribution law. A list of 14 globular clusters with the most significant capture probabilities is given, with five GCs—NGC 6266, NGC 6569, Terzan 5, NGC 6522, NGC 6540—showing the probability of capture by the bar <span>(Pgeq 0.2)</span>. A conclusion is made about the regularity of the orbits of globular clusters based on the calculation of approximations of the maximum characteristic Lyapunov exponents.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 4","pages":"499 - 513"},"PeriodicalIF":1.3,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140019354","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":"Dependence of Solar Supergranular Lifetime on Surface Magnetic Activity and Rotation","authors":"G. M. Sowmya,&nbsp;G. Rajani,&nbsp;U. Paniveni,&nbsp;R. Srikanth","doi":"10.1134/S1990341323600138","DOIUrl":"10.1134/S1990341323600138","url":null,"abstract":"<p>The lifetimes and length-scales for supergranular cells in active and quiescent regions of the solar chromosphere, and the relation between the two, were studied using a time series of Ca II K filtergrams. The lifetimes, in contrast to supergranular length scale and fractal dimension, show no significant dependence on solar latitude, suggesting that cell lifetimes are independent of the differential rotation and a possible supergranular super-rotation. The functional form of the relation was obtained guided by a comparison of the distributions of the two supergranular parameters. We infer a linear dependence of cell lifetime on area, which can be understood by the assumption of the network’s evolution via a diffusion of the magnetic field. Our analysis suggests that the diffusion rate in quiet regions is about 10<span>(%)</span> greater than in active regions.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 4","pages":"606 - 612"},"PeriodicalIF":1.3,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140019424","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":"Optical and Radio Variability of the Blazar S4 0954+658","authors":"V. V. Vlasyuk,&nbsp;Yu. V. Sotnikova,&nbsp;A. E. Volvach,&nbsp;O. I. Spiridonova,&nbsp;V. A. Stolyarov,&nbsp;A. G. Mikhailov,&nbsp;Yu. A. Kovalev,&nbsp;Y. Y. Kovalev,&nbsp;M. L. Khabibullina,&nbsp;M. A. Kharinov,&nbsp;L. Yang,&nbsp;M. G. Mingaliev,&nbsp;T. A. Semenova,&nbsp;P. G. Zhekanis,&nbsp;T. V. Mufakharov,&nbsp;R. Yu. Udovitskiy,&nbsp;A. A. Kudryashova,&nbsp;L. N. Volvach,&nbsp;A. K. Erkenov,&nbsp;A. S. Moskvitin,&nbsp;E. V. Emelianov,&nbsp;T. A. Fatkhullin,&nbsp;P. G. Tsybulev,&nbsp;N. A. Nizhelsky,&nbsp;G. V. Zhekanis,&nbsp;E. V. Kravchenko","doi":"10.1134/S1990341323600229","DOIUrl":"10.1134/S1990341323600229","url":null,"abstract":"<p>We present an optical-to-radio study of the BL Lac object\u0000S4 0954+658 observations during 1998–2023. The measurements were\u0000obtained with the SAO RAS Zeiss-1000 and AS-500/2 0.5-m telescopes\u0000in 2003–2023, with the RATAN-600 radio telescope at 1.25 (0.96,\u00001.1), 2.3, 4.7 (3.7, 3.9), 8.2 (7.7), 11.2, 22.3 (21.7) GHz in\u00001998–2023, with the IAA RAS RT-32 Zelenchukskaya and Badary\u0000telescopes at 5.05 and 8.63 GHz in 2020–2023, and with the RT-22\u0000single-dish telescope of CrAO RAS at 36.8 GHz in 2009–2023. In\u0000this period the blazar was showing extremely high broadband\u0000activity with the variability amplitude of the flux densities up\u0000to 70–100<span>(%)</span> both in the optical and radio domains. During the\u0000period of 2014–2023 the blazar displayed extremely high activity\u0000in the radio wavelengths, and we detected multiple radio flares of\u0000varying amplitude and duration. The large flares last on average\u0000from 0.3 to 1 year at 22–36.8 GHz and slightly longer at\u00005–11.2 GHz. The optical flares are shorter and last 7–50 days.\u0000The characteristic time scale <span>(tau)</span> of variation at 5–22 GHz is\u0000about 100 days in the most active epoch of 2014–2023 and about\u00001000 days for the state with lower activity in 2009–2014. We\u0000found a general correlation between the optical, radio, and\u0000<span>(gamma)</span>-ray flux variations, which suggesting that we observe the\u0000same photon population from different emission regions. We\u0000estimated the linear size of this region as 0.5–2 pc for\u0000different conditions. A broadband radio spectrum with two\u0000components of the S4 0954+658 jet was modeled using both\u0000electrons and protons as emitting particles. The results suggest\u0000that the synchrotron radio waves in this AGN may be produced by\u0000relativistic protons.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 4","pages":"464 - 486"},"PeriodicalIF":1.3,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140019461","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":"Satellites around Edge-on Galaxies. I. Dynamical Masses","authors":"D. V. Smirnov,&nbsp;D. I. Makarov,&nbsp;I. D. Karachentsev","doi":"10.1134/S1990341323600230","DOIUrl":"10.1134/S1990341323600230","url":null,"abstract":"<p>We have undertaken a search for satellites around edge-on galaxies\u0000in the EGIPS catalog, which contains 16 551 objects with\u0000declinations above <span>(-30^{circ})</span>. We searched for systems with a\u0000central galaxy dominating in brightness by at least\u0000<span>(1^{textrm{m}})</span> compared to its companions. As a result, we\u0000discovered 1097 candidate satellites around 764 EGIPS galaxies\u0000with projected distances less than 500 kpc and a radial velocity\u0000difference less than 300 km s<span>({}^{-1})</span>. Of these, 757 satellites\u0000around 547 central galaxies have radial velocity accuracies higher\u0000than 20 km s<span>({}^{-1})</span> and satisfy the gravitationally bound\u0000condition. The ensemble of satellites is characterized by an\u0000average projected distance of 84 kpc and an average radial\u0000velocity dispersion of 103 km s<span>({}^{-1})</span>. Treating small\u0000satellites as test particles moving on isotropic orbits around\u0000central EGIPS galaxies, we determined the projected (orbital)\u0000masses of the edge-on galaxies. Within the luminosity range of\u0000<span>(1.3times 10^{10})</span> to <span>(42times 10^{10})</span> <span>(L_{odot})</span>, the total\u0000mass of the systems is well described by a linear dependence\u0000<span>(log M_{p}propto 0.88logleftlangle L_{K}rightrangle_{textrm{g}})</span>\u0000with an average total mass-to-<span>(K)</span>-band luminosity equal\u0000to <span>((17.5pm 0.8) M_{odot}/L_{odot})</span>, which is typical for\u0000nearby spiral galaxies such as the Milky Way, M 31 and M 81.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 4","pages":"487 - 498"},"PeriodicalIF":1.3,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140019352","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":"The Interstellar Ti II Distance Scale","authors":"G. A. Galazutdinov,&nbsp;T. A. Santander,&nbsp;E. Babina,&nbsp;J. Krełowski","doi":"10.1134/S1990341323700219","DOIUrl":"10.1134/S1990341323700219","url":null,"abstract":"<p>We measured the equivalent widths (<span>(EW)</span>s) of interstellar Ti II absorption lines at <span>(lambda)</span> 3383.759 for about 250 reddened objects and found a good correlation of the <span>(EW)</span>s with distances to the background stars, estimated using Gaia DR3 parallaxes. Hipparcos trigonometric parallaxes were used for very bright objects which were not observed by Gaia. The Ti II based distance estimation procedure is similar to the well known Ca II-method (Megier et al., 2005, 2009). However, there are at least 3 advantages of the Ti II method: in contrast to interstellar Ca II H and K lines, blending of Ti II with stellar lines is not an issue even for late B stars; Ti II is to a much less extent influenced by the saturation effect; only a single line must be measured, i.e. there is only a single measurement error to be taken into account. The relation of between Ti II <span>(EW)</span> and distance is given by simple equation <span>(dapprox 30EW)</span>, where <span>(d)</span> is the distance in pc and <span>(EW)</span> is the equivalent width of the Ti II <span>(lambda)</span> 3383.759 line in mÅ.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 4","pages":"550 - 556"},"PeriodicalIF":1.3,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140019428","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":"The Nature of the Emission Spectrum of NGC 7793 P13: Testing the Supercritical Accretion Disk Wind Model","authors":"A. Kostenkov,&nbsp;A. Vinokurov,&nbsp;K. Atapin,&nbsp;Y. Solovyeva","doi":"10.1134/S1990341323700086","DOIUrl":"10.1134/S1990341323700086","url":null,"abstract":"<p>The optical spectra of ultraluminous X-ray sources (ULXs) show signs of powerful outflows of matter. These outflows are responsible for the formation of a significant portion of optical and ultraviolet emission in ULXs and can either be stellar winds of the donor stars or optically thick outflows (winds) from the surface of supercritical accretion disks. In the latter scenario the outflows are still expected to be similar to stellar winds of massive stars, which allows one to use the same methods for their study based on a comparison of the observed spectra with those simulated within the framework of non-LTE extended atmosphere models. In this paper, we simulate the optical spectrum of the ultraluminous X-ray pulsar NGC 7793 P13, assuming that its emission part is produced in the wind of the supercritical accretion disk. The estimated mass loss rate is about <span>(1.4times 10^{-5}M_{odot})</span> yr<span>({}^{-1})</span>. We consider the positive and negative aspects of the model and also discuss the applicability of the concept of supercritical disk winds to NGC 7793 P13 and to another well-known ultraluminous X-ray pulsar, NGC 300 ULX-1.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 3","pages":"395 - 411"},"PeriodicalIF":1.2,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71908737","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":"Bipolar Nebula AFGL 2688 in the System of Post-AGB Star V1610 Cyg","authors":"V. G. Klochkova,&nbsp;V. E. Panchuk,&nbsp;M. V. Yushkin","doi":"10.1134/S1990341323700128","DOIUrl":"10.1134/S1990341323700128","url":null,"abstract":"<p>We present a survey of the results of photometric and spectral observations of a nebula AFGL 2688 in the system of post-AGB star V1610 Cyg. Apart from the analysis of the published results, our new spectral observations of the star at the BTA over 2002–2022 are also given consideration. A new understanding of the kinematics of gas and dust in the lobes of the nebula has been obtained. The totality of published data, registered in a wide range of wavelengths, allows us to consider AFGL 2688 as a prototype nebula for the stars undergoing the post-AGB stage. An assumption on the variation of the chemical composition of the central star is made. We discuss the prospects for studying the object in the optical range.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 3","pages":"412 - 428"},"PeriodicalIF":1.2,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71908738","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":"Photometric Operation Mode of the ASTRONIRCAM Camera","authors":"A. M. Tatarnikov,&nbsp;S. G. Zheltoukhov,&nbsp;N. I. Shatsky,&nbsp;M. A. Burlak,&nbsp;N. A. Maslennikova,&nbsp;A. A. Vakhonin","doi":"10.1134/S1990341323600163","DOIUrl":"10.1134/S1990341323600163","url":null,"abstract":"<p>We explain the details of the photometric operation mode of the ASTRONICAM near-IR spectrograph camera mounted on the 2.5-m telescope of the Caucasian Mountain Observatory of the Sternberg Astronomical Institute and describe algorithms used for primary correction and overall pipeline reduction of the acquired data. We present the transformation equations from the 2MASS photometric system to the instrumental <span>(Y)</span>-band system. We derive color transformation coefficients between the instrumental photometric system and standard MKO-NIR (Mauna Kea Observatories Near-Infrared) system for the <span>(J)</span>, <span>(H)</span>, and <span>(K)</span>-band filters and show that the camera system is close to the standard photometric system. We found that in the case of observations at zenith, average background brightness level, and <span>(1^{primeprime})</span> seeing the stars with <span>(J=22^{textrm{m}})</span>, <span>(H=20overset{textrm{m}}{.}5)</span>, <span>(K=19overset{textrm{m}}{.}5)</span> can be measured with a 3000-s exposure at the signal-to-noise ratio <span>(SNR=3)</span>.</p>","PeriodicalId":478,"journal":{"name":"Astrophysical Bulletin","volume":"78 3","pages":"384 - 394"},"PeriodicalIF":1.2,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71908736","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}