Communications of the Byurakan Astrophysical Observatory最新文献

{"title":"Gaia EDR3 Data For Three Young Stellar Objects","authors":"K. Gigoyan, N. Azatyan, K. Gigoyan","doi":"10.52526/25792776-22.69.1-77","DOIUrl":"https://doi.org/10.52526/25792776-22.69.1-77","url":null,"abstract":"We present Gaia Early Data Release 3 (Gaia EDR3) high accurate astrometric and photometric data\u0000and also Catalina Sky Survey (CSS ) phase-dependent light curves for three Young Stellar Objects (YSO).\u0000They are LRL 245, 2MASS J04300424+3533238, and CVSO 592. These tree YSOs are presented as periodic variables in the Catalina Surveys Data Release-1 (CSDR1) data base.\u0000CSS phase-dependent curve of LRL 245 shows periodicity with period P=234.66 days and amplitude\u0000∆m≈4.0 mag. For this object high-resolution spectra in H-band (from 1.51 to 1.69 µm) was obtained by\u0000the APOGEE instrument. LAMOST telescope moderate-resolution CCD spectra is available for object\u00002MASS J04300424+3522238 only. The spectra shows clear features of M dwarfs.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121820336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On “Observational Instruments” composed of Stones No. 12, 13 and 14 of “Zorats Qarer” Monument","authors":"H. A. Malkhasyan","doi":"10.52526/25792776-22.69.1-100","DOIUrl":"https://doi.org/10.52526/25792776-22.69.1-100","url":null,"abstract":"The work is dedicated to the discussion of some of the stones of the “Zorats Qarer” megalithic\u0000monument (No. 12, 13 and 14) in terms of Astronomy. The methods of their use for observational\u0000purposes are revealed. Particularly, it has been shown that the stone No. 14 most likely served as\u0000a “seating platform” for the observer looking towards the observation angle of the stone No. 13.\u0000The other application method has been the formation of the exact direction by the principle of\u0000combining the angles of the stones No. 12 and 13. As a result of the usage of the aforementioned\u0000methods, three definite directions emerge. The examination of these directions has been performed\u0000for the possible date (9000 BC) which is crucial in terms of the origin of the ancient Armenian\u0000calendar (Protohaykian), as well as the results of the study of the monument gained so far. The results of the comprehensive examination have been combined with archeological material, Armenian\u0000ethnography and folklore. Comparisons have been drawn between days of observing the celestial\u0000bodies and important structural units of Protohaykian calendar. At the same time, the observation\u0000conditions and the mythological images of the observed stars have been discussed in the context\u0000of the most important stages of the cereal cultivation (sowing, harvesting, etc.). Parallels have\u0000been drawn with the Armenian religious beliefs (also of other nations), as well as with the results,\u0000already known from the study of this monument.\u0000The study of the mentioned stones has revealed that the stars (up to 2m.50 apparent magnitude),\u0000observable in 9000 BC, their mythological perceptions, observation conditions and days, are in\u0000complete harmony with the structure and content of the Protohaykian calendar (as well as of the\u0000ornament-calendar of the early Bronze Age vessel from Keti), and they are closely related to the\u0000worship of the Mother Goddess. Links between the observation positions and the definite stages\u0000of the cereal cultivation culture (autumn and spring sowing) reappear. There is no contradiction\u0000between previously and currently obtained results of the study of the monument. Moreover, the\u0000results obtained so far are complementary.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"6 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133060450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fine classification of the emission-line spectra of active galaxies","authors":"A. Mickaelian, H. Abrahamyan, G. Mikayelyan, G. Paronyan","doi":"10.52526/25792776-22.69.1-10","DOIUrl":"https://doi.org/10.52526/25792776-22.69.1-10","url":null,"abstract":"We refine the classification of galaxies by activity types based on a number of samples of objects\u0000having homogeneous optical medium resolution spectra from SDSS. SDSS spectra provide many spectral\u0000features and details that were not available before. Three diagnostic diagrams and eye examination have\u0000been used and the combined activity types have been derived. A fine classification scheme was developed,\u0000where QSOs have subtypes like Seyferts, Narrow Line QSOs are introduced, subclasses for Narrow Line\u0000Seyfert 1s are used and Composite spectrum objects have their subtypes. This classification scheme much\u0000better describes all fine details in the optical spectra and allows further study of active galaxies by the\u0000subtypes for better understanding the Unified model and the physical properties of AGN and Starbursts.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"2007 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127301051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can the Existence of Dark Energy Shed Light on the Dark\u0000Sides of the ”Byurakan Concept”?","authors":"H. Harutyunian","doi":"10.52526/25792776-22.69.1-1","DOIUrl":"https://doi.org/10.52526/25792776-22.69.1-1","url":null,"abstract":"The Ambartsumian’s idea on the existence of superdense matter and its decay due to evolution is considered using the new observational data. We suggest a new approach to the problem using the number density of baryons for describing the cosmic object instead of mass density. The atomic nuclei and baryons increase their mass due to the gradual decrease of the nuclear binding energy, which, in its turn, takes place as a result of the influence of dark energy. This effect increases the mass of all cosmic objects and the Universe as a whole. Apparently, the smart mechanism of transformation of the mass into energy and vice versa in the atomic nuclei level regulates mass density everywhere. The self-consistent change of the baryonic mass and their number density maintain the balance in the baryonic world.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"10 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126005141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Some studies on First Byurakan Survey late-type stars","authors":"K. Gigoyan","doi":"10.52526/25792776-22.69.1-90","DOIUrl":"https://doi.org/10.52526/25792776-22.69.1-90","url":null,"abstract":"Markarian survey (or the First Byurakan Survey, FBS), was the first systematic survey of the extragalactic sky. This objective-prism survey was carried out in 1965-1980 by B. E. Markarian and his\u0000colleagues using the 1 m Schmidt telescope of the Byurakan Astrophysical Observatory and resulted in\u0000discovery of 1517 UV-excess (Markarian) galaxies. FBS low-resolution spectral plates have been used long\u0000period to search and study faint late-type stars (LTSs, M-type and C(carbon) stars) at high galactic latitudes. I will review in this paper the results obtained for late-LTSs using FBS spectral plates. At present\u0000the survey is digitized and DFBS database is available. This paper reports also recent new discovered C\u0000and M-type stars, and a huge amount of the LTSs candidates selected in the DFBS data base. This paper\u0000informed also detecting some amount of the new dwarf carbon (dC) star candidates.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121718470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Astronomical Public Activities in Armenia","authors":"M. A. Asryan, S. Farmanyan, A. Mickaelian","doi":"10.52526/25792776-22.69.1-122","DOIUrl":"https://doi.org/10.52526/25792776-22.69.1-122","url":null,"abstract":"The Byurakan Astrophysical Observatory (BAO) founded by the outstanding scientist Viktor Ambartsumian in 1946 is one of the famous astronomical centers in the world, and particularly in the Eurasian\u0000area. Along with large scientific, scientific-organizational, and educational activities, public outreach is\u0000also very active. The paper gives an overview of BAO public activities in Armenia and in the region.\u0000We emphasize the significance of public activities in raising awareness among public on the topics of\u0000astronomy and science in general. BAO serves as a regional center for the IAU initiative Astronomy for\u0000Development and hosts the IAU South West and Central Asian (SWCA) ROAD, which has a number of\u0000activities, including many public ones.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115244278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gasdynamical flows in star forming regions","authors":"A. Yeghikyan","doi":"10.52526/25792776-22.69.1-32","DOIUrl":"https://doi.org/10.52526/25792776-22.69.1-32","url":null,"abstract":"A review of gas-dynamical flows in astrophysics is given with an emphasis on accretion flows and\u0000outflows. Analytical estimates of the dependence of the velocity and density on the radius during spherical\u0000accretion are considered, as well as the rate of mass inflow and the corresponding luminosity of the\u0000accretion disk are also estimated. Some features of gas inflow and outflow near the star are mentioned,\u0000like mass-loading flows where source functions of mass and momentum are presented and analyzed. The\u0000velocities and radii of the ionization fronts of hot stars are considered. The Sedov-Taylor analytical\u0000formula on the dependence of the radius of the fireball on time during a strong explosion is given, where\u0000the explosion energy and density of the medium act as parameters. Examples of the use of dimensional\u0000theory in astrophysics, in particular, in accretion flows used above are considered. An example of a\u0000numerical solution of the interaction of an interstellar cloud with the solar wind is also given, followed by\u0000an estimate of the inflow of the cloud’s gas environment into the Earth’s atmosphere, which affects the\u0000terrestrial ozone content.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132095537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth of accreting intermediate mass black hole seeds","authors":"G. Ter-Kazarian","doi":"10.52526/25792776-22.69.1-47","DOIUrl":"https://doi.org/10.52526/25792776-22.69.1-47","url":null,"abstract":"This communication aims to review the mass assembly history of seed black holes to the present time\u0000of accreting intermediate mass black hole (IMBH)-candidates. Given the masses and redshifts at present\u0000time of 137 IMBH-candidates collected from the literature, we have undertaken a large series of numerical\u0000simulations to achieve this goal. The crux is that, we utilize the microscopic theory of black hole (MTBH),\u0000which explores the most important novel aspects expected from considerable change of properties of spacetime continuum at spontaneous breaking of gravitation gauge symmetry far above nuclear density. As\u0000a corollary, this theory has smeared out the central singularities of BHs, and makes room for their\u0000growth and merging behavior. We compute among the others the masses, the growth-time scales, TBH,\u0000and the redshifts of seed BHs. In particular, for the present masses log(M/[M⊙]) = 2.20 to 5.99 of\u0000IMBH-candidates, the computed seed masses are ranging from log(Mseed/[M⊙]) = −0.50 to 3.29, with\u0000corresponding growth-time scales TBH ranging from log(TBH/[yr]) = 8.82 to 10.09. We derived scaling\u0000mass-luminosity relation, by means of which we compute the luminosities of IMBH-candidates ranging\u0000from log(L/[erg s−1\u0000]) = 39.13 to 41.653.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130834369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Composition of super-Earths, super-Mercuries, and their host stars","authors":"V. Adibekyan, N. Santos, C. Dorn, S. Sousa, A. Hakobyan, B. Bitsch, C. Mordasini, S. Barros, E. D. Mena, O. Demangeon, J. Faria, P. Figueira, B. M. T. B. Soares, G. Israelian","doi":"10.52526/25792776-2021.68.2-447","DOIUrl":"https://doi.org/10.52526/25792776-2021.68.2-447","url":null,"abstract":"Because of their common origin, it was assumed that the composition of planet building blocks should, to a first order, correlate with stellar atmospheric composition, especially for refractory elements. In fact, information on the relative abundance of refractory and major rock-forming elements such as Fe, Mg, Si has been commonly used to improve interior estimates for terrestrial planets. Recently Adibekyan et al. (2021) presented evidence of a tight chemical link between rocky planets and their host stars. In this study we add six recently discovered exoplanets to the sample of Adibekyan et al and re-evaluate their findings in light of these new data. We confirm that i) iron-mass fraction of rocky exoplanets correlates (but not a 1:1 relationship) with the composition of their host stars, ii) on average the iron-mass fraction of planets is higher than that of the primordial f star iron , iii) super-Mercuries are formed in disks with high iron content. Based on these results we conclude that disk-chemistry and planet formation processes play an important role in the composition, formation, and evolution of super-Earths and super-Mercuries.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125917487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Modern Space Situational Awareness System","authors":"T. Jackson, H. Holland, G. Tuparev, M. Steinbatz, W. Promper, D. Weinzinger","doi":"10.52526/25792776-22.69.2-318","DOIUrl":"https://doi.org/10.52526/25792776-22.69.2-318","url":null,"abstract":"We, Tuparev AstroTech in partnership with Astro Syteme Austria, present a next-generation Space Situational Awareness (SSA) system currently being created for the tracking and characterisation of satellites and space debris in the age of big-data astronomy. Our SSA system will be based on the image processing of white-light images to detect streaks produced by satellites and space debris. These images will be obtained by a network of 20-30 custom and in-house built SSA observatory stations, which will be made operational worldwide over the coming decade. The system will use machine learning algorithms to choose the optimal part of the sky to observe at any given moment, analyse the incoming data on-site and in real-time, and deliver various standardised data packages and science-quality images to be stored on a bespoke central archive capable of storing petabytes of data. With this system, we aim to cover a greater geographical and celestial area than any previous SSA system, to create a scalable system that is both fast and efficient, and to enable access to orders of magnitude more storage capacity and information than any other system currently available, commercial or governmental.","PeriodicalId":412578,"journal":{"name":"Communications of the Byurakan Astrophysical Observatory","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114689153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}