Communications of the Byurakan Astrophysical Observatory (ComBAO)
Volume 64, Issue 1, Dec 2017
Preface from Editorial Board 0.1 MB
Alternative paradigm for the cosmic objects formation: New prospects 0.3 MB
Haik A. Harutyunian
Abstract. We consider here briefly the cosmogonic concept suggested by Viktor Ambartsumian in the last century for explaining the formation of cosmic objects. He grounded his concept using the observational facts available in 40s-60s of the last century. The analysis of observational data allowed him to conclude that cosmic objects formation takes place up to nowadays. The second and more “heretical” conclusion he arrived at persuades that the origination and further evolution of cosmic objects goes on in course of gradual decay of proto-stellar matter at all hierarchical levels. We argue that this approach appeared first time in Ambartsumian’s papers devoted to the problems of quantum electrodynamics. Later on his concept on objects formation due to decay of protostellar dense matter was rejected because the known laws of physics do not allow existence of huge masses consisted of superdense matter. We bring to the readers’ attention, that the discovery of dark energy changes the situation drastically and opens new rooms for the ideas forgotten by the scientific community.
Multiwavelength search and studies of active galaxies and quasars 1 MB
Areg M. Mickaelian
Abstract. The Byurakan Astrophysical Observatory (BAO) has always been one of the centres for surveys and studies of active galaxies. Here we review our search and studies of active galaxies during last 30 years using various wavelength ranges, as well as some recent related works. These projects since late 1980s were focused on multiwavelength search and studies of AGN and Starbursts (SB). 1103 blue stellar objects (BSOs) on the basis of their UV-excess were selected using Markarian Survey (First Byurakan Survey, FBS) plates and Markarian’s criteria used for the galaxies. Among many blue stars, QSOs and Seyfert galaxies were found by follow-up observations. 1577 IRAS point sources were optically identified using FBS low-dispersion spectra and many AGN, SB and high-luminosity IR galaxies (LIRG/ULIRG) were discovered. 32 extremely high IR/opt flux ratio galaxies were studies with Spitzer. 2791 ROSAT FSC sources were optically identified using Hamburg Quasar Survey (HQS) low-dispersion spectra and many AGN were discovered by follow-up observations. Fine analysis of emission line spectra was carried out using spectral line decomposition software to establish true profiles and calculate physical parameters for the emitting regions, as well as to study the spectral variability of these objects. X-ray and radio selection criteria were used to find new AGN and variable objects for further studies. We have estimated AGN content of X-ray sources as 52.9%. We have also combined IRAS PSC and FSC catalogs and compiled its extragalactic sample, which allowed us to estimate AGN content among IR sources as 23.7%. Multiwavelength approach allowed revealing many new AGN and SB and obtaining a number of interesting relations using their observational characteristics and physical properties.
Color-color diagrams in near infrared: (J-H)/(H-K). I 0.4 MB
Armen L. Gyulbudaghian, N. Baloian, I. A. Sanchez
Abstract. In the paper are presented the color-color diagrams (J-H)/(H-K) for all stars with visible values B<11, for which in the known catalogs the values of J, H, K, and also spectral classes and luminosity classes of these stars are given. The diagrams are constructed for luminosity classes Ia, Ib, II, III, IV, V. The similarity of diagrams for classes Ia and Ib (super giants) and II (giants), is obvious from these diagrams. The diagrams obtained by us can be used for discovering of new young stars and also for determining of color excesses of investigating stars. Maximal amounts of stars are registered in the classes V and III. There is a tendency of increasing of J-H and H-K along the sequence of spectral classes O – M, which is correct for all luminosity classes.
Calculation of Gaussian quadrature with high accuracy mathematics package 0.2 MB
Abstract. We are checking here the dependence of numerical integration accuracy on the quantity of integration points and the accuracy of machine representation of numbers. For this purpose, the package HAHMath is applied. This package allows one to carry out calculations with arbitrary long machine decimal numbers, presented as vectors of integers. Integrals are substituted for Gaussian sums where Hermite polynomials zeros and corresponding weights are used. It is shown that for the chosen case the accuracy of final calculations depends on the used machine numbers more strictly than on the quantity of the integration points.
Cosmological Views of Anania Shirakatsi 0.3 MB
Sona V. Farmanyan, Areg M. Mickaelian
Abstract. Since the ancient times the usage of cosmological ideas in mythology and poetry has contributed to the formation and development of human’s philosophical thought. It is believed that before the M. Mashtots’salphabet, ancient Armenians have expressed their astronomical knowledge through stone structures and rock art.In the Armenian reality, the cosmological views, the idea of the spherical shape of the Earth and information of other celestial bodies more vividly were manifested in the works of Movses Khorenatsi, David Anhaght (5th century) and Anania Shirakatsi (7th century).Anania Shirakatsi is an Armenian Astronomer, Mathematician, Philosopher, Geographer and Alchemist.The importance of his work is also noted by foreign authors and he was called 7th century Cosmologist, First Scientist of Armenia and Middival Astronomer. Shirakatsi’s works are united in his comprehensive knowledge, his insight of the mind, the ability of combining and analyzing facts and his literature talent.His works have simultaneous historical, cosmic, geographical, religious, literary and mystical significance. In the present study we will show Anania Shirakatsi’s cosmological ideas and observations.
Rock carvings of Armenia 11 MB
Karen S. Tokhatyan
Speckle Interferometric Observations on 2.6 m telescope of BAO 0.3 MB
J. A. Docobo, J. Gomez, N. D. Melikian , G. Paronyan
Abstract. Speckle observations with a PhotonMax EMCCD detector from Princeton Instruments were carried out for the first time in the 2.6 m telescope of BAO. Three observing campaigns were already completed. More than four hundred objets had been observed, relative positions and differential photometry information will be published during next months. Throughout the text we provide general information regarding the campaigns, the camera configuration, the EMCCD technical characteristics, and the reduction procedure. Also a brief discussion on how to determine the angle without the 180º ambiguity is included.
New Capabilities of One-Meter Schmidt Telescope of the Byurakan Astrophysical Observatory after modernization 0.6 MB
T. A. Movsessian, S. N. Dodonov, V. V. Gabrielyan, S. S. Kotov, M. Gevorgyan
Abstract. Within the framework of cooperation between Byurakan Astrophysical Observatory and Special Astrophysical Observatory during 2013–2015 y the 1-m Schmidt telescope of the Byurakan Astrophysical was upgraded. We completely redesigned the control system of the telescope: we replaced the actuating mechanisms, developed telescope control software, and made the guiding system. In the Special Astrophysical Observatory, the 4k×4k Apogee (USA) liquid-cooled CCD was reworked and prepared. Detector was mounted in the focus of the telescope and provides 1-degree field of view with pixel-size of 0.868, and RON∼11e−. The detector is equipped with a turret with 5 holes for filters. The 20 intermediate-band filters (FWHM= 250A) uniformly covering the 4000–9000AA wavelength range, five broadband filters (u, g, r, i, z SDSS), and three narrow-band filters. During the first year of test operation of the 1-m telescope we performed pilot observations within the framework of three programs: search for young stellar objects, AGN evolution, and stellar composition of galaxy disks. We confirmed the possibility of efficiently selecting of young objects using observations performed in narrow-band Hα and [S II] filters and the intermediate-band 7500̊A filter. Three-hours long exposures with SDSS g, r, and i band filters allow us to reach the surface brightness level of 28m from square arcsecond when investigating the stellar content of galaxy disks for a sample of nine galaxies. We used observations performed with the 1-m telescope in five broadband (SDSS u, g, r, i, and z) and 15 intermediate-band filters (4000–7500A) to construct a sample of quasar candidates with 0.5<z<5 (330 objects) in about one-sq. degree SA 68 field complete down to RAB=23m. Spectroscopic observations of 29 objects (19.m5<R<22m) carried out at the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences confirmed the quasar nature of 28 objects.
BAO Plate Archive Project 1 MB
A. M. Mickaelian, K. S. Gigoyan, M. V. Gyulzadyan, G. M. Paronyan, H. V. Abrahamyan, H. R. Andreasyan, N. M. Azatyan, G. R. Kostandyan, A. L. Samsonyan, G. A. Mikayelyan, S. V. Farmanyan, V. L. Harutyunyan
Abstract. We present the Byurakan Astrophysical Observatory (BAO) Plate Archive Project that is aimed at digitization, extraction and analysis of archival data and building an electronic database and interactive sky map. BAO Plate Archive consists of 37,500 photographic plates and films, obtained with 2.6m telescope, 1m and 0.5m Schmidt telescopes and other smaller ones during 1947-1991. The famous Markarian Survey (or the First Byurakan Survey, FBS) 2000 plates were digitized in 2002-2005 and the Digitized FBS (DFBS, www.aras.am/Dfbs/dfbs.html) was created. New science projects have been conducted based on this low-dispersion spectroscopic material. Several other smaller digitization projects have been carried out as well, such as part of Second Byurakan Survey (SBS) plates, photographic chain plates in Coma, where the blazar ON 231 is located and 2.6m film spectra of FBS Blue Stellar Objects. However, most of the plates and films are not digitized. In 2015, we have started a project on the whole BAO Plate Archive digitization, creation of electronic database and its scientific usage. Armenian Virtual Observatory (ArVO, www.aras.am/Arvo/arvo.htm) database will accommodate all new data. The project runs in collaboration with the Armenian Institute of Informatics and Automation Problems (IIAP) and will continues during 4 years in 2015-2018. The final result will be an Electronic Database and online Interactive Sky map to be used for further research projects. ArVO will provide all standards and tools for efficient usage of the scientific output and its integration in international databases.
New observational project for revealing natural and anthropogenic threats at the near-Earth space 1.7 MB
Haik Harutyunian, Elena Nikoghosyan, Norayr Melikian, Naira Azatyan, Hayk Abrahamyan, Gurgen Paronyan, Hasmik Andreasyan, Gabriel Ohanian, Mkrtich Gevorgyan, Gor Mikayelyan
Abstract. In 2014, a new monitoring project started at the observational base Saravand of the Byurakan astrophysical observatory. This project initiated for revealing natural and artificial objects at the near-Earth space. This is a kind of continuation of earlier observational projects implemented at the observatory prior the collapse of Soviet Union. This time, near-Earth space monitoring is carried out at the request of the Russian agency ROSKOSMOS. For observations, the EOP-1 module is used, which includes small telescopes with a mirror diameter of 40cm, 25cm and 19cm.
Ecology of Near-Earth Space 0.4 MB
E. H. Nikoghosyan
Abstract. The technical achievements of our civilization are accompanied by certain negative consequences affect the near-Earth space. The problem of clogging of near-Earth space by "space debris" as purely theoretical arose essentially as soon as the first artificial satellite in 1957 was launched. Since then, the rate of exploitation of outer space has increased very rapidly. As a result, the problem of clogging of near-Earth space ceased to be only theoretical and transformed into practical. Presently, anthropogenic factors of the development of near-Earth space are divided into several categories: mechanical, chemical, radioactive and electromagnetic pollution.
IAU South West and Central Asian Regional Office of Astronomy for Development 0.8 MB
A. M. Mickaelian, S. A. Hakopian, S. V. Farmanyan, G. A. Mikayelyan
Abstract. The International Astronomical Union (IAU) announced its Strategic Plan on Astronomy for Development in 2009, during the International Year of Astronomy (IYA). One of its main components was the creation of the Office of Astronomy for Development (OAD) and corresponding Regional Offices (ROADs) for implementation and coordination of its aims. The OAD was created in Cape Town, South Africa and later on ROADs were created in 8 regions. Since 2015, Armenia hosts one of them, IAU South West Asian (SWA), later renamed to South West and Central Asian (SWCA) ROAD. At present, already 6 countries have officially joined (Armenia, Georgia, Iran, Kazakhstan, Tajikistan, and Turkey), but the Office serves for a rather broad region, from Eastern Europe to Central Asia. Armenia’s geographical location and its historical role in astronomy (both for well-known archaeoastronomical heritage and the presence of the famous Byurakan Astrophysical Observatory (BAO) founded by Viktor Ambartsumian in 1946) serve as a link between Europe and Eastern Partnership countries, Middle East and Asia in general. We run activities in 3 directions, Task Forces (TF): TF1 Universities and Research, TF2 Children and Schools and TF3 Public Outreach. We present our projects and all other accomplishments and discuss the role of our ROAD in maintaining contacts and development of astronomy in the region, as well as contacts between Europe and the Eastern Partnership countries. Most up-to-date information about the IAU SWCA ROAD is available on its webpage at http://iau-swa-road.aras.am/eng/index.php.