Radio Investigations of Clusters of Galaxies
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Marat Arakelian: Life and Scientific Activity 0.7 MB
Communications of BAO, Vol. 66, Issue 2, 2019, pp. 112-120 Marat Arakelian: Life and Scientific Activity A. M. Mickaelian∗ NAS RA Byurakan Astrophysical Observatory (BAO), Byurakan 0213, Aragatzotn Province, Armenia Abstract 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 specialist in the theoretical astrophysics and extragalactic astronomy. Keywords: active galaxies, AGN, Starburst Galaxies, quasars, Seyfert galaxies, LINERs Introduction Prof. Arakelian is 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 specialist in the theoretical astrophysics and extragalactic as- tronomy. Life and Activities Marat Arsen Arakelian was born on January 15, 1929, in Goris, Armenia, USSR. He studied at the Physical-Mathematical Department of the Yerevan State University (YSU) and graduated from ∗[email protected], Corresponding author A. M. Mickaelian 112 DOI: 10.52526/25792776-2019.66.2-112 Marat Arakelian: Life and Scientific Activity it in 1951, among the first students specialized on Astrophysics. He was directed to the Byurakan Astrophysical Observatory (BAO), where he worked first as assistant astronomer, and later as junior research associate. Soon he became a postgraduate student at the Leningrad State University (LSU, presently, St. Petersburg), finished the studies in 1955, and in 1956 successfully passed his Ph.D. -
Galaxy Clusters in Radio → Non-Thermal Phenomena
GalaxyGalaxy ClustersClusters inin radioradio ÎÎ NonNon--thermalthermal phenomenaphenomena Luigina Feretti Istituto di Radioastronomia CNR Bologna, Italy Tonanzintla, GH2005, 4-5 July 2005 Lecture 4 : Radio emission from cluster galaxies: Classical radio galaxies Radio – X-ray interaction Distorted structures: NAT and WAT Radio galaxies filling X-ray cavities Confinement : Trigger of radio emission: radio luminosity function Enhancement of star formation RadiogalaxiesRadiogalaxies X-ray:X-ray: ThermalThermal ggasas Radio:Radio: AA 119119 (z(z == 0.0441)0.0441) RadioRadio GalaxiesGalaxies PerseusPerseus X-rayX-ray ROSAROSATT PSPCPSPC HotHot gasgas NGC 1265 RadioRadio WSRTWSRT 4949 cmcm RadioRadio galaxiesgalaxies NGC 1275 IC310 RadioRadio galaxiesgalaxies ooff highhigh andand lowlow ppowerower havehave quitequite differentdifferent morphologiesmorphologies onon thethe largelarge scalescale (Fanaroff(Fanaroff && RileyRiley 11974)974) CygCyg AA FRFR IIII 24.24.55 -1-1 HighHigh popowewer:r: PP1.41.4 GHzGHz >> 1010 WW HzHz 3C3C 444499 24.524.5 -1-1 LowLow power:power: PP1.41.4 GHzGHz << 1010 WW HzHz FRFR II RADIORADIO GALAXIESGALAXIES ATAT INCREASINGINCREASING RADIORADIO POWERPOWER 1024 W Hz-1 at 1.4 GHz 3C 31 DA 240 4C 73.08 1026.5 W Hz-1 From Atlas of P.Leahy, powers computed With H0=75, q0=0.5 Owen and Ledlow 1994 TheThe radioradio emissionemission fromfrom INDIVIDUALINDIVIDUAL GALAXIESGALAXIES isis foufoundnd ttoo extendextend WELLWELL BEYONDBEYOND thethe physicalphysical sizesize ofof thethe hosthost opticaloptical galaxygalaxy (>(> oror -
RADIO ASTRONOMY OBERVTORY Quarterly Report CHARLOTTESVILLE, VA
1 ; NATIONAL RADIO ASTRONOMY OBSERVATORY Charlottesville, Virginia t PROPERTY OF TH E U.S. G - iM RADIO ASTRONOMY OBERVTORY Quarterly Report CHARLOTTESVILLE, VA. 4 OCT 2 2em , July 1, 1984 - September 30, 1984 .. _._r_.__. _.. RESEARCH PROGRAMS 140-ft Telescope Hours Scheduled observing 1853.75 Scheduled maintenance and equipment changes 205.00 Scheduled tests and calibration 145.25 Time lost due to: equipment failure 122.00 power 3.25 weather 0.25 interference 14.50 The following continuum program was conducted during this quarter. No. Observer Program W193 N. White (European Space Observations at 6 cm of the eclipsing Agency) RS CVn system AR Lac. J. Culhane (Cambridge) J. Kuijpers (Utrecht) K. Mason (Cambridge) A. Smith (European Space Agency) The following line programs were conducted during this quarter. No. Observer Program B406 M. Bell (Herzberg) Observations at 13.9 GHz in search of H. Matthews (Herzberg) C6 H in TMC1. T. Sears (Brookhaven) B422 M. Bell (Herzberg) Observations at 3 cm to search for H. Matthews (Herzberg) C5 H in TMC1 and examination of T. Sears (Brookhaven) spectral features in IRC+10216 thought to be due to HC 9 N or C5 H. B423 M. Bell (Herzberg) Observations at 9895 MHz in an attempt H. Matthews (Herzberg) to detect C3 N in absorption against Cas A. 2 No. Observer Program B424 W. Batria Observations at 9.1 GHz of a newly discovered comet. C216 F. Clark (Kentucky) Observations at 6 cm and 18 cm of OH S. Miller (Kentucky) and H20 to study stellar winds and cloud dynamics. -
The Dynamical State of the Coma Cluster with XMM-Newton?
A&A 400, 811–821 (2003) Astronomy DOI: 10.1051/0004-6361:20021911 & c ESO 2003 Astrophysics The dynamical state of the Coma cluster with XMM-Newton? D. M. Neumann1,D.H.Lumb2,G.W.Pratt1, and U. G. Briel3 1 CEA/DSM/DAPNIA Saclay, Service d’Astrophysique, L’Orme des Merisiers, Bˆat. 709, 91191 Gif-sur-Yvette, France 2 Science Payloads Technology Division, Research and Science Support Dept., ESTEC, Postbus 299 Keplerlaan 1, 2200AG Noordwijk, The Netherlands 3 Max-Planck Institut f¨ur extraterrestrische Physik, Giessenbachstr., 85740 Garching, Germany Received 19 June 2002 / Accepted 13 December 2002 Abstract. We present in this paper a substructure and spectroimaging study of the Coma cluster of galaxies based on XMM- Newton data. XMM-Newton performed a mosaic of observations of Coma to ensure a large coverage of the cluster. We add the different pointings together and fit elliptical beta-models to the data. We subtract the cluster models from the data and look for residuals, which can be interpreted as substructure. We find several significant structures: the well-known subgroup connected to NGC 4839 in the South-West of the cluster, and another substructure located between NGC 4839 and the centre of the Coma cluster. Constructing a hardness ratio image, which can be used as a temperature map, we see that in front of this new structure the temperature is significantly increased (higher or equal 10 keV). We interpret this temperature enhancement as the result of heating as this structure falls onto the Coma cluster. We furthermore reconfirm the filament-like structure South-East of the cluster centre. -
Brightest Cluster Galaxies and Intracluster Light - Observations Magda Arnaboldi European Southern Observatory (Garching) O
Brightest cluster galaxies and intracluster light - Observations Magda Arnaboldi European Southern Observatory (Garching) O. Gerhard, L. Coccato, G. Ventimiglia, S. Okamura P. Das, M. Doherty, K. Freeman, E. Mc Neil, N. Yasuda, J.A.L. Aguerri, R. Ciardullo, K. Dolag, J.J. Feldmeier, G.H. Jacoby. M. Arnaboldi – BCGs and ICL: observations ESO, FVC+, 27 June - 01 July 2011 1 Outline 1. Brightest Cluster Galaxies and Intracluster light in clusters 2. Planetary nebulae as kinematical tracers 3. The Virgo cluster & M87 – The PNs’ VLOS and the projected phase space distribution – Dynamical status of the Virgo core – Large scale distribution of the ICL 4. The Hydra cluster & NGC 3311 – Observations : long-slit spectroscopy, MSIS, surface photometry – Debris from disrupted galaxies by the cluster potential 5. The Coma cluster core & the NGC 4874/NGC 4889 binary merger 6. Conclusions M. Arnaboldi – BCGs and ICL: observations ESO, FVC+, 27 June - 01 July 2011 2 1. ICL from deep photometry • Core of the Coma cluster: Photographic photometry Thuan & Kormendy 1977 • Abell 4010 (left, z=0.096) Abell 3888 (center, z=0.151) Deep CCD photometry Krick & Bernstein 2007 Abell 1914 (right) Feldmeier+2004 See also Melnick+’77, Bernstein ’95, Feldmeier+’04, Gonzalez+’05, Mihos+’05, Krick+’06 See contributions from J. Krick, J. Melnick, C. Rudick, S. Okamura M. Arnaboldi – BCGs and ICL: observations ESO, FVC+, 27 June - 01 July 2011 3 ICL properties in individual clusters • ICL surface brightness profile shape varies between clusters - Krick & Bernstein 2007 • Ellipticity generally increases with radius, position angle sometimes has sharp variations - Gonzalez + 2005 • Suggests ICL is dynamically young and separate from BCG PA (o) 50 0 -50 1 10 100 (kpc/h) 4 M. -
THE GLOBULAR CLUSTER SYSTEM of the COMA CD GALAXY NGC 4874 from HUBBLE SPACE TELESCOPE ACS and WFC3/IR IMAGING* Hyejeon Cho1, John P
The Astrophysical Journal, 822:95 (23pp), 2016 May 10 doi:10.3847/0004-637X/822/2/95 © 2016. The American Astronomical Society. All rights reserved. THE GLOBULAR CLUSTER SYSTEM OF THE COMA CD GALAXY NGC 4874 FROM HUBBLE SPACE TELESCOPE ACS AND WFC3/IR IMAGING* Hyejeon Cho1, John P. Blakeslee2, Ana L. Chies-Santos3,4, M. James Jee1, Joseph B. Jensen5, Eric W. Peng6,7, and Young-Wook Lee1 1 Department of Astronomy and Center for Galaxy Evolution Research, Yonsei University, Seoul 03722, Korea; [email protected], [email protected] 2 NRC Herzberg Astronomy & Astrophysics, Victoria, BC V9E 2E7, Canada; [email protected] 3 Departamento de Astronomia, Instituto de Física, UFRGS, Porto Alegre, R.S. 91501-970, Brazil 4 Departamento de Astronomia, IAGCA, Universidade de São Paulo, 05508-900 São Paulo, SP, Brazil 5 Department of Physics, Utah Valley University, Orem, Utah 84058, USA 6 Department of Astronomy, Peking University, Beijing 100871, China 7 Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China Received 2016 January 31; accepted 2016 April 4; published 2016 May 11 ABSTRACT We present new Hubble Space Telescope (HST) optical and near-infrared (NIR) photometry of the rich globular cluster (GC) system NGC 4874, the cD galaxy in the core of the Coma cluster (Abell 1656). NGC 4874 was observed with the HST Advanced Camera for Surveys in the F475W (g475) and F814W (I814) passbands and with the Wide Field Camera3 IR Channel in F160W (H160). The GCs in this field exhibit a bimodal optical color distribution with more than half of the GCs falling on the red side at g475−I814>1. -
Curriculum Vitae John P
Curriculum Vitae John P. Blakeslee National Research Council of Canada Phone: 1-250-363-8103 Herzberg Astronomy & Astrophysics Programs Fax: 1-250-363-0045 5071 West Saanich Road Cell: 1-250-858-1357 Victoria, B.C. V9E 2E7 Email: [email protected] Canada Citizenship: USA Education 1997 Ph.D., Physics, Massachusetts Institute of Technology (supervisor: Prof. John Tonry) 1991 B. A., Physics, University of Chicago (Honors; supervisor: Prof. Donald York) Employment History 2007 – present Astronomer, Senior Research Officer NRC Herzberg Institute of Astrophysics 2008 – present Adjunct Associate Professor Department of Physics, University of Victoria 2008 – 2013 Adjunct Professor Washington State University 2005 – 2007 Assistant Professor of Physics Washington State University 2004 – 2005 Research Scientist Johns Hopkins University 2000 – 2004 Associate Research Scientist Johns Hopkins University 1999 – 2000 Postdoctoral Research Associate University of Durham, U.K. 1996 – 1999 Fairchild Postdoctoral Scholar California Institute of Technology Fellowships and Awards 2004 Ernest F. Fullam Award for Innovative Research in Astronomy, Dudley Observatory 2003 NASA Certificate for contributions to the success of HST Servicing Mission 3B 1996 – 1999 Sherman M. Fairchild Postdoctoral Fellowship in Astronomy, Caltech Professional Service 2016 – present Canadian Large Synoptic Survey Telescope (LSST) Consortium, Co-PI 2014 – present Chair, NOAO Time Allocation Committee (TAC) Extragalactic Panel 2008 – present National Representative, Gemini International -
University of Groningen the Galaxy Population in the Coma Cluster Beijersbergen, Marco
University of Groningen The galaxy population in the Coma cluster Beijersbergen, Marco IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below. Document Version Publisher's PDF, also known as Version of record Publication date: 2003 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Beijersbergen, M. (2003). The galaxy population in the Coma cluster. s.n. Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons). The publication may also be distributed here under the terms of Article 25fa of the Dutch Copyright Act, indicated by the “Taverne” license. More information can be found on the University of Groningen website: https://www.rug.nl/library/open-access/self-archiving-pure/taverne- amendment. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. Download date: 07-10-2021 4 A Catalogue of Galaxies in the Coma Cluster Morphologies, Luminosity Functions and Cluster Dynamics M. Beijersbergen & J. M. van der Hulst ABSTRACT — We present a new multi-color catalogue of 583 spectroscopically confirmed members of the Coma cluster based on a deep wide field survey covering 5.2 deg2. -
The Herschel Sprint PHOTO ILLUSTRATION: PATRICIA GILLIS-COPPOLA, HERSCHEL IMAGE: WIKIMEDIA S&T
The Herschel Sprint PHOTO ILLUSTRATION: PATRICIA GILLIS-COPPOLA, HERSCHEL IMAGE: WIKIMEDIA S&T 34 April 2015 sky & telescope William Herschel’s Extraordinary Night of DiscoveryMark Bratton Recreating the legendary sweep of April 11, 1785 There’s little doubt that William Herschel was the most clearly with his instruments. As we will see, he did make signifi cant astronomer of the 18th century. His accom- occasional errors in interpretation, despite the superior plishments included the discovery of Uranus, infrared optics; for instance, he thought that the planetary nebula radiation, and four planetary satellites, as well as the M57 was a ring of stars. compilation of two extensive catalogues of double and The other factor contributing to Herschel’s interest multiple stars. His most lasting achievement, however, was the success of his sister, Caroline, in her study of the was his exhaustive search for undiscovered star clusters sky. He had built her a small telescope, encouraging her and nebulae, a key component in his quest to understand to search for double stars and comets. She located Messier what he called “the construction of the heavens.” In Her- objects and more, occasionally fi nding star clusters and schel’s time, astronomers were concerned principally with nebulae that had escaped the French astronomer’s eye. the study of solar system objects. The search for clusters Over the course of a year of observing, she discovered and nebulae was, up to that point, a haphazard aff air, with about a dozen star clusters and galaxies, occasionally not- a total of only 138 recorded by all the observers in history. -
Extragalactic Astronomy: the U Nivcre Bey Nd Our Galaxy
U1IJT RESUPE EU 1J3 199 021 775 dacon Eenneth Char TITLE Extragalactic Astronomy: The U nivcre Bey nd Our Galaxy. American Astronomical Society, Princeton, N.J. SFONS AGENCY National Aeronautics and Space Administra ashingtonl D.C.; National Science Foundation, Washington, D.C. REPOBT NO NASA-i:T-129 PUB DATE Sep 76 NOTE 44p.; FOF ltEd aocunents, _e SE 021 773-776 AVAII,AULE Superintendent of Documents, U.S. G-vernment Prin ing Office, Washington, D.C. 20402(5 ock Number 033-000-00657-8, $1.30) E.-RS PE10E 1F-$0.03 HC-$2.06 Plus Postige. DESCilIPTORS *Astronomy; Curriculum; *Instructional Materials; Science Education; *Scientific iesearch; Secondary Education; *Secondary School Science; *Space Sciences TIF NASA; National Aeronautics and Space Administration BSTRACT This booklet is part of an American Astronomical Society curriculum project designed to provide teaching materials to teachers or secondary school chemistry, physics, and earth science. The material is presented in three parts: one section provides the fundamental content of extragalactic astronomy, another section discusses modern discoveries in detail, and the last section summarizes the earlier discussions within the structure of the Big Bang Theory of Evolution. Each of the three sections is followed by student exercises and activities, laboratory projects, and questions and answers. The glossary contains unfamiliar terms used in the text and a collection of teacher aids such as literature references and audiovisual materials. (111) ***** *** * ** ** ***************** ********** Document., acquired by IC include many informal unpublished aterials not available from other sources. ERIC makes every effort * * to obtain the best copy available. Nevertheless, items of marginal * * reproducibility are often encountered and tbis affects the quality * * of the microfiche and hardcopy reproductions ERIC makes available * * via the ERIC Document Reproduction Service (EDRS). -
195 9Apj. . .130. .629B the HERCULES CLUSTER OF
.629B THE HERCULES CLUSTER OF NEBULAE* .130. G. R. Burbidge and E. Margaret Burbidge 9ApJ. Yerkes and McDonald Observatories Received March 26, 1959 195 ABSTRACT The northern of two clusters of nebulae in Hercules, first listed by Shapley in 1933, is an irregular group of about 75 bright nebulae and a larger number of faint ones, distributed over an area about Io X 40'. A set of plates of parts of this cluster, taken by Dr. Walter Baade with the 200-inch Hale reflector, is shown and described. More than three-quarters of the bright nebulae have been classified, and, of these, 69 per cent are spirals or irregulars and 31 per cent elliptical or SO. Radial velocities for 7 nebulae were obtained by Humason, and 10 have been obtained by us with the 82-inch reflector. The mean red shift is 10775 km/sec. From this sample, the total kinetic energy of the nebulae has been esti- mated. By measuring the distances between all pairs on a 48-inch Schmidt enlargement, the total poten- tial energy has been estimated. From these results it is concluded that, if the cluster is to be in a stationary state, the average galactic mass must be ^1012Mo. Three possibilities are discussed: that the masses are indeed as large as this, that there is a large amount of intergalactic matter, and that the cluster is expanding. The data for the Coma and Virgo clusters are also reviewed. It is concluded that both the Hercules and the Virgo clusters are probably expanding, but the situation is uncertain in the case of the Coma cluster. -