Areg Mickaelian

Byurakan Astrophysical Observatory | BAO · Extragalactic Astronomy

We study the close proximity of the well-known and well-studied 3C31 class FRI radio galaxy in order to reveal the influence of the environment on an extragalactic radio source. It was shown that about 110 million years ago the galaxies NGC 380 and NGC 386 were located near the galaxy NGC 383 (the parent galaxy of 3C31). On the other hand, the mode...

Astronomical surveys and catalogs are the main sources for the discovery of new objects, both Galactic and extragalactic. Archives and Databases maintain billions of astronomical objects; planets, comets, stars, exoplanets, nebulae, galaxies, and quasars. We will review the current background in astronomy for further all-sky or large-area studies....

Because the Earth’s atmosphere is not transparent for the most of the electromagnetic waves, Space Astronomy was born in 1960s to complement ground-based observations and to provide us with multiwavelength data from gamma-ray to radio. Most Space observatories work in gamma-ray, X-ray, UV and IR, as well as there are also optical and other Space te...

We have carried out a number of studies to reveal radio properties of active galaxies, namely AGN and Starbursts. A major work was related to the cross-correlation of NVSS and FIRST radio catalogues and revelation of variable radio sources. Most probably, most of them are extragalactic ones; AGN and Starbursts. We have carried out spectroscopic cla...

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 area. Along with large scientific, scientific-organizational, and educational activities, public outreach is also very active. The paper gives an overv...

We refine the classification of galaxies by activity types based on a number of samples of objects having homogeneous optical medium resolution spectra from SDSS. SDSS spectra provide many spectral features and details that were not available before. Three diagnostic diagrams and eye examination have been used and the combined activity types have b...

The discovery and study of new White Dwarfs (WDs) is extremely important for understanding the kinematics and dynamicsof the local stellar population. They are evolutionary signatures of the Milky Way, as most of stars pass through thisevolutionary stage. We have carried out a statistical analysis of the White Dwarfs Catalogue to establish their av...

This article is a presentation of a project which is a statistical study of white dwarfs’ properties carried out based on the sample of the First Byurakan Survey Blue Stellar Objects (FBS BSOs) and the Catalogue of White Dwarfs. Using these results, we have searched and will continue to search for new white dwarfs by means of Gaia accurate astromet...

Introduction: Successful search for meteorites allows specifying the initial mass of the body, adjust the destruction model, and clarify the criteria for the fallout of meteorites [1,2]. Unlike meteorite finds, less than four dozen cases have been registered when, based on the photo and video data, it was possible to find meteorites and determine p...

In this paper we investigate radio properties of active galaxies taken from Veron-Cetty & Veron (2010) catalogue. The galaxies are limited to magnitudes in the range of 12m-19m. We have cross-correlated the list with radio catalogues and selected those galaxies, which have data on 5 radio fluxes at different wavelengths. For all the objects we have...

The analysis of blazars’ parameters from BZCAT leads to a conclusion that they do not have the same properties. The preliminary criterion to include an object in the catalog was the strong radio emission; however, two type of radio sources were selected: BL Lacertae (BLL) objects and Flat Spectrum Radio Quasars (FSRQ). As a number of properties are...

The First Byurakan Survey (FBS) 2nd Part was devoted to search and studies of Blue Stellar Objects (BSOs) and Late-type Stars. Eleven lists of 1103 BSOs were published in Astrophysics in 1990-1996, found in FBS low-dispersion spectroscopic plates. The selection was carried out in the region with +33◦ > δ > +45◦ and δ >+61◦ with a surface of ∼4000 d...

A general catalog of active galactic nuclei (AGN) has been created from identified optical sources of X-ray data from the Hamburg-ROSAT Catalog (HRC) and the Byurakan-Hamburg ROSAT Catalog (BHRC). Optical and multiwavelength data from both catalogs have been examined in order to eliminate erroneous AGN and add new ones. The result is a new catalog...

Using the SDSS spectroscopy, we have carried out optical spectral classification for activity types for some 2500 candidate AGN using pre-selection by various samples; bright objects of The Catalog of Quasars and Active Galactic Nuclei, AGN candidates among X-ray sources, optically variable and other samples of radio sources, IRAS PSC/FSC extragala...

Using the SDSS spectroscopy, we have carried out fine optical spectral classification for activity types for 710 AGN candidates. These objects come from a larger sample of some 2500 candidate AGN using pre-selection by various samples; bright objects of The Catalog of Quasars and Active Galactic Nuclei, AGN candidates among X-ray sources, optically...

The Digitized First Byurakan Survey is the largest and the first systematic objective-prism survey of the extragalactic sky. The detection, extraction, and classification of about 40 million spectra of about 20 million astronomical objects available in the survey require distinguishing the pixels containing photons from the source and the noise pix...

The Byurakan Astrophysical Observatory (BAO) is one of the most famous observatories of the Soviet Union and may be of the world. It was founded in 1946 by the outstanding scientist Viktor Ambartsumian (1908-1996) and became the leader of studies on instability phenomena in the Universe. Many discoveries have been carried out at BAO related to star...

We present the recent results of 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 some 37,000 photographic plates and films, obtained with 2.6m telescope, 1m and 0.5m Sc...

Markarian survey (or the First Byurakan Survey, FBS) was the first systematic survey for active galaxies and was a new method for search for such objects. Until now, it is the largest objective prism survey of the sky (17,000 deg2). It was carried out in 1965-1980 by B. E. Markarian and his colleagues and resulted in discovery of 1517 UV-excess (Ma...

The famous Markarian Survey (or the First Byurakan Survey, FBS) was carried out in 1965-1980. Its 2000 plates were digitized in 2002-2007 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. The Armenian Virtual Observatory (ArVO, www.aras...

A review on the activities and achievements of the Armenian Astronomical Society (ArAS) and the Armenian astronomy in general is given on the occasion of the 20th anniversary of the official foundation of ArAS. ArAS membership, ArAS electronic newsletters (ArASNews), ArAS webpage, Annual Meetings, Annual Prize for Young Astronomers (Yervant Terzian...

This is a detailed spectral classification of 96 active galaxies from the Véron-Cetty and Véron catalog (2010, Version 13, VCV-13) of active galaxies and quasars. These objects were identified as radio sources using standard radio catalogs. Those galaxies which had radio sources in at least 6 different radio bands and had been identified spectrally...

This is a detailed spectral classification of 198 candidate active galactic nuclei (AGN) from a joint HRC/BHRC sample consisting of a combination of the HRC (Hamburg-ROSAT) and BHRC (Byurakan-ROSAT) catalogs. These objects have been identified as optical counterparts of ROSAT x-ray sources, but spectra for 198 of them are given in the SDSS without...

A report on the activities and achievements of the Armenian Astronomical Society (ArAS) and the Armenian astronomy in general during the last years is given. ArAS membership, ArAS electronic newsletters (ArASNews), ArAS webpage, Annual Meetings, Annual Prize for Young Astronomers (Yervant Terzian Prize) and other awards, international relations, pa...

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 O...

The paper gives an overview of BAO Outreach Activities and Scientific Journalism in Armenia. We emphasize the role of scientific journalism in raising awareness among public on the topics of astronomy and science in general.

Armenia is a country with rich history, as well as high-level science. It is rich in scientific, particularly in astronomical sites, among which archaeological sites related to science, medieval universities, modern scientific institutions and science related museums can be mentioned. Examples of archaeological sites are ancient observatories, petr...

The Digitized First Byurakan Survey has digitized and processed about 1900 photographic plates from the objective prism surveys conducted in Byurakan by Benjamin Markarian and collaborators in the 1960ies and 1970ies. After digitization, a custom web service was built and operated first in Rome, then in Trieste. However, as astronomical data system...

The Astrophysical Virtual Observatories (AVOs) have been created in a number of countries using their available databases and current observing material as a collection of interoperating data archives and software tools to form a research environment in which complex research programs can be conducted. Among all these data, a large spectroscopic da...

We present the modern situation in astronomy, where Big Data coming from the Universe put new tasks for catalogizing, storage, archiving, analysis and usage of the scientific information. The two major characteristics of modern astronomy are multiwavelength (MW) studies (from γ-ray to radio, as well as multi-messenger studies, using also neutrinos,...

We present surveys and related studies of active galaxies carried out at the Byurakan Astrophysical Observatory (BAO). This was one of the main research subjects at BAO during many years, since mid-1950s, when Viktor Ambartsumian suggested the hypothesis of the activity of the galactic nuclei. A number of surveys and searches for Active Galactic Nu...

Observational archives are the main source for most of the astronomical studies, as given observations cannot entirely solve any problem and need to be complemented by related observing data both for construction of the time domain, multiwavelength, multi-technique and multi-method picture. This relates to both modern observations and historical on...

We present the recent results of studies on active galaxies (both AGN and Starbursts) by the Extragalactic group of Byurakan Astrophysical Observatory (BAO) Research Department "Astro-nomical Surveys". The research has been carried out in 2017-2019 and the results are published in 2018-2019. These studies are characterized by multiwavelength approa...

Astronomy in Armenia was popular since ancient times and Armenia is rich in its astronomical heritage, such as ancient and medieval Armenian calendars, records of astronomical events by ancient Armenians, the astronomical heritage of the Armenian medieval great thinker Anania Shirakatsi, etc. Armenian astronomical archives have accumulated vast num...

We review Big Data in Astronomy and its role in Astronomy Education. At present all-sky and large-area astronomical surveys and their catalogued data span over the whole range of electromagnetic spectrum, from gamma-ray to radio, as well as most important surveys giving optical images, proper motions, variability and spectroscopic data. Most import...

Bright IR galaxies (LIRG, ULIRG, and HLIRG) are important for research on star formation processes in the early universe since they can be detected at large distances owing to their luminosity. High IR is indicative of active star formation and starburst (SB) processes, which are typical of HII regions. In many cases high IR is indicative of an act...

A total of 18 lists of the First Byurakan Survey of Late-Type Stars (FBS LTS) were published between 1990 and 2016. The stars were found on FBS low-dispersion spectroscopic plates. A systematic search and selection were carried out on a surface of ∼16 000 deg2 on almost the whole area of the FBS. As a result, the ‘Revised and Updated Catalogue of t...

In this work we try to understand some optical properties of blazars having uncertain types (BZU) in BZCAT vs. 5 Catalogue. Cross-correlation with SDSS reveals 43 BZU out of 227 that have spectra in SDSS. We have carried out spectral reclassification for these 43 blazar candidates (BZU) for activity types. As a result, 37 (86%) objects out of 43 ch...

The paper is a summary and general analysis of optical spectroscopic data on 257 Byurakan-IRAS Galaxies (BIG objects) obtained with the BAO 2.6-m, SAO 6-m, OHP 1.93-m telescopes and taken from SDSS spectroscopic database. 149 star-formation regions galaxies, 42 galaxies with active nuclei, and 28 galaxies with a composite spectrum were identified....

The paper is a summary and general analysis of optical spectroscopic data on 257 Byurakan-IRAS Galaxies (BIG objects) obtained with the BAO 2.6-m, SAO 6-m, OHP 1.93-m telescopes and taken from SDSS spectroscopic database. 149 star-formation regions galaxies, 42 galaxies with active nuclei, and 28 galaxies with a composite spectrum were identified....

The analysis of blazars' parameters from BZCAT leads to a conclusion that they do not have the same properties. The preliminary criterion to include an object in the catalog was the strong radio emission; however, two type of radio sources were selected: BL Lacertae (BLL) objects and Flat Spectrum Radio Quasars (FSRQ). As a number of properties are...

In this study we carry out detailed spectral classification of 173 AGN candidates from the Joint HRC/BHRC sample, which is a combination of HRC (Hamburg-ROSAT Catalogue) and BHRC (Byurakan-Hamburg-ROSAT Catalogue). These objects were revealed as optical counterparts for ROSAT X-ray sources; however, spectra for 173 of them are given in SDSS without...

The field of exoplanetary science is making rapid progress both in statistical studies of exoplanet properties as well as in individual characterization. As space missions provide an emerging picture of formation and evolution of exoplanetary systems, the search for habitable worlds becomes one of the fundamental issues to address. To tackle such a...

A review about Space related activities in Armenia is given, particularly in the Byurakan Astrophysical Observatory (BAO, Armenia), including the first Space Astronomy projects by Grigor Gurzadian in 1960s-1970s (Orion and Orion-2 UV observatories), research projects with USA (NASA) and European (ESA) Space observatories (IRAS, ROSAT, Hubble, Spitz...

We review the life and scientific activity of one of the outstanding Armenian astronomers Marat Arakelian (1929-1983). Arakelian was one of the prominent Byurakan astronomers, the author of famous Arakelian galaxies, which at present are target for many-sided studies with ground-based and space telescopes. Arakelian is known as a distinguished spec...

Results of comparison of Gaia DR2 parallaxes with data derived from a combined analysis of 2MASS (Two Micron All-Sky Survey), SDSS (Sloan Digital Sky Survey), GALEX (Galaxy Evolution Explorer), and UKIDSS (UKIRT Infrared Deep Sky Survey) surveys in four selected high-latitude | b | > 48° sky areas are presented. It is shown that multicolor photomet...

The history of the International Astronomical Union (IAU) meetings goes back to 1922 when the first IAU General Assembly (GA) was held in Rome, Italy, following the IAU creation in 1919. However, until 1953, no individual symposia were organized and the GAs were the only official gatherings for astronomers. All together, eight IAU GAs were held dur...

Results of comparison of Gaia DR2 parallaxes with data derived from a combined analysis of 2MASS (Two Micron All-Sky Survey), SDSS (Sloan Digital Sky Survey), GALEX (Galaxy Evolution Explorer), and UKIDSS (UKIRT Infrared Deep Sky Survey) surveys in four selected high-latitude $|b|>48^{\circ}$ sky areas are presented. It is shown that multicolor pho...

The UV properties of 1152 Markarian galaxies have been investigated based on GALEX data. These objects have been investigated also in other available wavelengths using multi-wavelength data from X-ray to radio. Using our classification for activity types for 779 Markarian galaxies based on SDSS spectroscopy, we have investigated these objects on th...

Overview of IAU OAD Regional Offices and Language Centres - Volume 14 Symposium - Rosa Doran, German Chaparro, S. V. Farmanyan, Jaime E. Forero-Romero, Angela Patricia Perez Henao, Wichan Insiri, Awni Khasawneh, M. B. N. Kouwenhoven, Joana Latas, A. M. Mickaelian, G. A. Mikayelyan, George Miley, Lenganji M. Mutembo, Bonaventure Okere, Pedro Russo,...

Information on interstellar extinction and dust properties may be obtained from modern large photometric surveys data. Virtual Observatory facilities allow users to make a fast and correct cross-identification of objects from various surveys. It yields a multicolor photometry data on detected objects and makes it possible to estimate stellar parame...

This work is dedicated to reclassification of LINERs. For our investigation we use the catalogueVéron-Cetty&Véron13th edition. In this catalogue 926 LINERs are included. Cross-correlation of these sources with SDSS DR14 gives 176 objects which have spectra in SDSS. Having medium-resolution spectra from SDSS we have done reclassification of these so...

This work is dedicated to reclassification of LINERs. For our investigation we use the catalogueVéron-Cetty&Véron13th edition. In this catalogue 926 LINERs are included. Cross-correlation of these sources with SDSS DR14 gives 176 objects which have spectra in SDSS. Having medium-resolution spectra from SDSS we have done reclassification of these so...

High-luminosity IR galaxies (LIRGs, ULIRGs, and HLIRGs) are important for studies related to star-formation processes in the early Universe, as their luminosity allows to detect them at large distances. High IR indicates active star-formation and often starburst processes, which is typical to HII (starburst, SB) and AGN. An interesting question is...

Eighteen lists of late-type stars (LTSs) have been published between 1990 and 2016. These LTSs have been found in the low-dispersion spectroscopic plates of the First Byurakan Survey (FBS). The systematic search and selection was carried out on a surface _16000 deg2 on almost the whole area of the FBS. As a result, \Revised And Updated Catalogue Of...

We give a review of the most important scientific achievements of one of the greatest scientists of the XX century, the founder of the modern astrophysics in Armenia, Viktor A. Ambartsumian (1908-1996). He has fundamentally contributed in various fields of astronomy and astrophysics, cosmogony, theoretical physics, mathematics, and philosophy. We l...

We analyse the oxygen and nitrogen abundance and specific star formation rates (sSFR) in Markarian galaxies from Sloan Digital Sky Survey (SDSS) spectra. The Data Release 7 (DR7) of SDSS contains photometric data for more there 1000 and spectral information for more than 700 Markarian objects. The Mrk sample has played a central role in the task of...

In this study we carry out detailed spectral classification of 123 AGN candidates from the Joint HRC/BHRC sample, which is a combination of HRC (Hamburg-ROSAT Catalogue) and BHRC (Byurakan-Hamburg-ROSAT Catalogue). These objects were revealed as optical counterparts for ROSAT X-ray sources, however spectra for 123 of them are given in SDSS-III, IV...

The present study is devoted to the introduction of the outreach activities of IAU South West and Central Asia Regional Office of Astronomy for Development (SWCA ROAD) Significant communications gap between scientists and society is rendered. We show how to gain new enthusiasts of the Universe by science popularization. We point out the positive ou...

An overview of the current activities of the Armenian astronomy, including professional research, University and school education, public outreach and other organizational affairs. We show that present day Armenian astronomy serves as a leader for the regional activities, as well as is among the most advanced and active sciences in Armenia. Moreove...

We have studied several color-color infrared diagrams of the 276 late type stars of the BIS catalog. For 95 of these stars we derived spectral classification from our slit spectroscopy. From the 2MASS color diagram we derive that none of the sample stars is a dwarf. The WISE 3.4-12 vs 12-22 plot is the best to discriminate the variability type (Mir...

Through the analysis and interpretation of newly obtained and of literature data we have clarified the nature of poorly investigated IRAS point sources classified as late type stars, belonging to the Byurakan IRAS ~Stars catalog. From medium resolution spectroscopyof 95 stars we have strongly revised 47 spectral types and newly classified 31 source...

We review the status of all-sky and large astronomical surveys and their catalogued data over the whole range of electromagnetic spectrum, from gamma-ray to radio, such as ROSAT in X-ray, GALEX in UV, SDSS and several POSS1/2 based catalogs (APM, MAPS, USNO, GSC) in optical, 2MASS and WISE in NIR, IRAS and AKARI in MIR/FIR, NVSS and FIRST in radio...

The aim of the article is to introduce the data sharing service of the Armenian Virtual Observatory (ArVO) based on the Simple Image Access (SIA) Protocol of the International Virtual Observatory Alliance (IVOA).

Recent all-sky and large-area astronomical surveys and their catalogued data over the whole range of electromagnetic spectrum are reviewed, from Gamma-ray to radio, such as Fermi-GLAST and INTEGRAL in Gamma-ray, ROSAT, XMM and Chandra in X-ray, GALEX in UV, SDSS and several POSS I and II based catalogues (APM, MAPS, USNO, GSC) in optical range, 2MA...

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 st...

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...

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 O...

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 cos...

Statistical studies of active galaxies (both AGN and Starburst) using large multi-wavelength data are presented, including new studies of Markarian galaxies, large sample of IR galaxies, variable radio sources, and large homogeneous sample of X-ray selected AGN. Markarian survey (the First Byurakan Survey) was digitized and the DFBS database was cr...

The Digitised First Byurakan Survey (DFBS) provides low dispersion optical spectra for about 24 million sources. A two-step machine learning algorithm based on similarities to predefined templates is applied to select different classes of rare objects in the dataset automatically, for example late type stars, quasars and white dwarves. Identifying...

The First Byurakan Survey (FBS) is the largest spectral survey in the Northern sky. One can select objects by color, broad absorption and emission lines, and SED; classify and investigate them. The digitization of the FBS is aimed at making a DFBS database available for the astronomical community. Besides scanning, we are creating plate solutions,...

Two major characteristics of modern astronomy are multiwavelength (MW) studies (fromγ-ray to radio) and big data (data acquisition, storage and analysis). Present astronomical databases and archives contain billions of objects observed at various wavelengths, both galactic and extragalactic, and the vast amount of data on them allows new studies an...

The joint catalogue of Active Galactic Nuclei selected from optical identifications of X-ray sources was created as a combination of two samples: Hamburg-ROSAT Catalogue (HRC) and Byurakan-Hamburg-ROSAT Catalogue (BHRC). Both are based on optical identifications of X-ray sources from ROSAT catalogues using low-dispersion spectra of Hamburg Quasar S...

The Byurakan Astrophysical Observatory (BAO, Armenia, http://www.bao.am) are among the candidate IAU Regional Nodes for Astronomy for Development activities. It is one of the main astronomical centers of the former Soviet Union and the Middle East region. At present there are 48 qualified researchers at BAO, including six Doctors of Science and 30...

High–redshift quasars and blazars are among the most powerful sources in the Universe and among the highest luminosity sources, as in optical, so as in X–ray, UV, IR and radio range. We have created a full sample of blazars and high–redshift quasars ( z ≥2.15). The evolutionary relation of high–redshift quasars and blazars to high–redshift galaxies...