A Multi-Wavelength Investigation of Seyfert 1.8 and 1.9 Galaxies
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Expanding Space, Quasars and St. Augustine's Fireworks
Universe 2015, 1, 307-356; doi:10.3390/universe1030307 OPEN ACCESS universe ISSN 2218-1997 www.mdpi.com/journal/universe Article Expanding Space, Quasars and St. Augustine’s Fireworks Olga I. Chashchina 1;2 and Zurab K. Silagadze 2;3;* 1 École Polytechnique, 91128 Palaiseau, France; E-Mail: [email protected] 2 Department of physics, Novosibirsk State University, Novosibirsk 630 090, Russia 3 Budker Institute of Nuclear Physics SB RAS and Novosibirsk State University, Novosibirsk 630 090, Russia * Author to whom correspondence should be addressed; E-Mail: [email protected]. Academic Editors: Lorenzo Iorio and Elias C. Vagenas Received: 5 May 2015 / Accepted: 14 September 2015 / Published: 1 October 2015 Abstract: An attempt is made to explain time non-dilation allegedly observed in quasar light curves. The explanation is based on the assumption that quasar black holes are, in some sense, foreign for our Friedmann-Robertson-Walker universe and do not participate in the Hubble flow. Although at first sight such a weird explanation requires unreasonably fine-tuned Big Bang initial conditions, we find a natural justification for it using the Milne cosmological model as an inspiration. Keywords: quasar light curves; expanding space; Milne cosmological model; Hubble flow; St. Augustine’s objects PACS classifications: 98.80.-k, 98.54.-h You’d think capricious Hebe, feeding the eagle of Zeus, had raised a thunder-foaming goblet, unable to restrain her mirth, and tipped it on the earth. F.I.Tyutchev. A Spring Storm, 1828. Translated by F.Jude [1]. 1. Introduction “Quasar light curves do not show the effects of time dilation”—this result of the paper [2] seems incredible. -
The Morphology of Minor Axis Gaseous Outflows in Edge-On Seyfert Galaxies
A&A 464, 541–552 (2007) Astronomy DOI: 10.1051/0004-6361:20065454 & c ESO 2007 Astrophysics The morphology of minor axis gaseous outflows in edge-on Seyfert galaxies, T. P. Robitaille1,, J. Rossa2,3,D.J.Bomans4,andR.P.vanderMarel2 1 SUPA, School of Physics and Astronomy, University of St. Andrews, North Haugh, KY16 9SS St. Andrews, UK e-mail: [email protected] 2 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA e-mail: [email protected] 3 Department of Astronomy, University of Florida, 211 Bryant Space Science Center, PO Box 112055, Gainesville, FL 32611, USA e-mail: [email protected] 4 Astronomisches Institut, Ruhr-Universität Bochum, Universitätsstrasse 150/NA7, 44780 Bochum, Germany e-mail: [email protected] Received 18 April 2006 / Accepted 20 December 2006 ABSTRACT Context. Spiral galaxies often have extended outflows that permeate beyond the region of the disk. Such outflows have been seen both in starburst galaxies, actively star forming galaxies and galaxies with an AGN. In the latter galaxies it is unknown whether the large-scale outflows are driven by star formation activity or purely by the active nucleus. Aims. The aim of our investigation is to study the frequency of extended minor-axis outflows in edge-on Seyfert galaxies to investigate the role of the AGN, the circumnuclear environment and star formation activity within the disk regions, and their importance for IGM enrichment on large scales. Methods. We obtained optical narrowband imaging observations of a distance limited, northern hemisphere sample of 14 edge-on Seyfert spiral galaxies. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
X-Ray Jets Aneta Siemiginowska
Chandra News Issue 21 Spring 2014 Published by the Chandra X-ray Center (CXC) X-ray Jets Aneta Siemiginowska The Active Galaxy 4C+29.30 Credit: X-ray: NASA/CXC/SAO/A.Siemiginowska et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA Contents X-ray Jets HETG 3 Aneta Siemiginowska 18 David Huenemoerder (for the HETG team) 10 Project Scientist’s Report 20 LETG Martin Weisskopf Jeremy Drake 11 Project Manager’s Report 23 Chandra Calibration Roger Brissenden Larry David Message of Thanks to Useful Web Addresses 12 Harvey Tananbaum 23 The Chandra Team Belinda Wilkes Appointed as CIAO 4.6 13 Director of the CXC 24 Antonella Fruscione, for the CIAO Team Of Programs and Papers: Einstein Postdoctoral Fellowship 13 Making the Chandra Connection 29 Program Sherry Winkelman & Arnold Rots Andrea Prestwich Chandra Related Meetings Cycle 14 Peer Review Results 14 and Important Dates 30 Belinda Wilkes ACIS Chandra Users’ Committee 14 Paul Plucinsky, Royce Buehler, 34 Membership List Gregg Germain, & Richard Edgar HRC CXC 2013 Science Press 15 Ralph Kraft, Hans Moritz Guenther 35 Releases (SAO), and Wolfgang Pietsch (MPE) Megan Watzke The Chandra Newsletter appears once a year and is edited by Paul J. Green, with editorial assistance and layout by Evan Tingle. We welcome contributions from readers. Comments on the newsletter, or corrections and additions to the hardcopy mailing list should be sent to: [email protected]. Spring, 2014 3 X-ray Jets many unanswered questions, including the nature of relativistic jets, jet energetics, particle content, parti- Aneta Siemiginowska cle acceleration and emission processes. Both statis- tical studies of large samples of jets across the entire The first recorded observation of an extragalac- electromagnetic spectrum and deep broad-band imag- tic jet was made almost a century ago. -
INTEGRAL View Of
INTEGRAL view of AGN Angela Maliziaa,∗, Sergey Sazonovb, Loredana Bassania, Elena Piana, Volker Beckmannc, Manuela Molinaa, Ilya Mereminskiyb, Guillaume Belangerd aOAS-INAF, Via P. Gobetti 101, 40129 Bologna, Italy bSpace Research Institute, Russian Academy of Sciences, Profsoyuznaya 84/32, 117997 Moscow, Russia cInstitut National de Physique Nuclaire et de Physique des Particules (IN2P3) CNRS, Paris, France dESA/ESAC, Camino Bajo del Castillo, 28692 Villanueva de la Canada, Madrid, Spain Abstract AGN are among the most energetic phenomena in the Universe and in the last two decades INTEGRAL’s contribution in their study has had a significant impact. Thanks to the INTEGRAL extragalactic sky surveys, all classes of soft X-ray detected (in the 2-10 keV band) AGN have been observed at higher energies as well. Up to now, around 450 AGN have been catalogued and a conspicuous part of them are either objects observed at high-energies for the first time or newly discovered AGN. The high-energy domain (20-200 keV) represents an important window for spectral studies of AGN and it is also the most appropriate for AGN population studies, since it is almost unbiased against obscuration and therefore free of the limitations which affect surveys at other frequencies. Over the years, INTEGRAL data have allowed to characterise AGN spectra at high energies, to investigate their absorption properties, to test the AGN unification scheme and to perform population studies. In this review the main results are reported and INTEGRAL’s contribution to AGN science is highlighted for each class of AGN. Finally, new perspectives are provided, connecting INTEGRAL’s science with that at other wavelengths and in particular to the GeV/TeV regime which is still poorly explored. -
IRS Observations of Seyfert 1.8 and 1.9 Galaxies: a Comparison with Seyfert 1 and Seyfert 2 R
University of Kentucky UKnowledge Physics and Astronomy Faculty Publications Physics and Astronomy 12-10-2007 Spitzer IRS Observations of Seyfert 1.8 and 1.9 Galaxies: A Comparison with Seyfert 1 and Seyfert 2 R. P. Deo Georgia State University D. M. Crenshaw Georgia State University S. B. Kraemer Catholic University of America M. Dietrich Ohio State University Moshe Elitzur University of Kentucky, [email protected] See next page for additional authors Right click to open a feedback form in a new tab to let us know how this document benefits oy u. Follow this and additional works at: https://uknowledge.uky.edu/physastron_facpub Part of the Astrophysics and Astronomy Commons, and the Physics Commons Repository Citation Deo, R. P.; Crenshaw, D. M.; Kraemer, S. B.; Dietrich, M.; Elitzur, Moshe; Teplitz, H.; and Turner, T. J., "Spitzer IRS Observations of Seyfert 1.8 and 1.9 Galaxies: A Comparison with Seyfert 1 and Seyfert 2" (2007). Physics and Astronomy Faculty Publications. 203. https://uknowledge.uky.edu/physastron_facpub/203 This Article is brought to you for free and open access by the Physics and Astronomy at UKnowledge. It has been accepted for inclusion in Physics and Astronomy Faculty Publications by an authorized administrator of UKnowledge. For more information, please contact [email protected]. Authors R. P. Deo, D. M. Crenshaw, S. B. Kraemer, M. Dietrich, Moshe Elitzur, H. Teplitz, and T. J. Turner Spitzer IRS Observations of Seyfert 1.8 and 1.9 Galaxies: A Comparison with Seyfert 1 and Seyfert 2 Notes/Citation Information Published in The Astrophysical Journal, v. -
Galaxies: Outstanding Problems and Instrumental Prospects for the Coming Decade (A Review)* T (Cosmology/History of Astronomy/Quasars/Space) JEREMIAH P
Proc. Natl. Acad. Sci. USA Vol. 74, No. 5, pp. 1767-1774, May 1977 Astronomy Galaxies: Outstanding problems and instrumental prospects for the coming decade (A Review)* t (cosmology/history of astronomy/quasars/space) JEREMIAH P. OSTRIKER Princeton University Observatory, Peyton Hall, Princeton, New Jersey 08540 Contributed by Jeremiah P. Ostriker, February 3, 1977 ABSTRACT After a review of the discovery of external It is more than a little astonishing that in the early part of this galaxies and the early classification of these enormous aggre- century it was the prevailing scientific view that man lived in gates of stars into visually recognizable types, a new classifi- a universe centered about himself; by 1920 the sun's newly cation scheme is suggested based on a measurable physical quantity, the luminosity of the spheroidal component. It is ar- discovered, slightly off-center position was still controversial. gued that the new one-parameter scheme may correlate well The discovery was, ironically, due to Shapley. both with existing descriptive labels and with underlying A little background to this debate may be useful. The Island physical reality. Universe hypothesis was not new, having been proposed 170 Two particular problems in extragalactic research are isolated years previously by the English astronomer, Thomas Wright as currently most fundamental. (i) A significant fraction of the (2), and developed with remarkably prescience by Emmanuel energy emitted by active galaxies (approximately 1% of all galaxies) is emitted by very small central regions largely in parts Kant, who wrote (see refs. 10 and 23 in ref. 3) in 1755 (in a of the spectrum (microwave, infrared, ultraviolet and x-ray translation from Edwin Hubble). -
Monthly Newsletter of the Durban Centre - March 2018
Page 1 Monthly Newsletter of the Durban Centre - March 2018 Page 2 Table of Contents Chairman’s Chatter …...…………………….……….………..….…… 3 Andrew Gray …………………………………………...………………. 5 The Hyades Star Cluster …...………………………….…….……….. 6 At the Eye Piece …………………………………………….….…….... 9 The Cover Image - Antennae Nebula …….……………………….. 11 Galaxy - Part 2 ….………………………………..………………….... 13 Self-Taught Astronomer …………………………………..………… 21 The Month Ahead …..…………………...….…….……………..…… 24 Minutes of the Previous Meeting …………………………….……. 25 Public Viewing Roster …………………………….……….…..……. 26 Pre-loved Telescope Equipment …………………………...……… 28 ASSA Symposium 2018 ………………………...……….…......…… 29 Member Submissions Disclaimer: The views expressed in ‘nDaba are solely those of the writer and are not necessarily the views of the Durban Centre, nor the Editor. All images and content is the work of the respective copyright owner Page 3 Chairman’s Chatter By Mike Hadlow Dear Members, The third month of the year is upon us and already the viewing conditions have been more favourable over the last few nights. Let’s hope it continues and we have clear skies and good viewing for the next five or six months. Our February meeting was well attended, with our main speaker being Dr Matt Hilton from the Astrophysics and Cosmology Research Unit at UKZN who gave us an excellent presentation on gravity waves. We really have to be thankful to Dr Hilton from ACRU UKZN for giving us his time to give us presentations and hope that we can maintain our relationship with ACRU and that we can draw other speakers from his colleagues and other research students! Thanks must also go to Debbie Abel and Piet Strauss for their monthly presentations on NASA and the sky for the following month, respectively. -
Active Galactic Nuclei - Suzy Collin, Bożena Czerny
ASTRONOMY AND ASTROPHYSICS - Active Galactic Nuclei - Suzy Collin, Bożena Czerny ACTIVE GALACTIC NUCLEI Suzy Collin LUTH, Observatoire de Paris, CNRS, Université Paris Diderot; 5 Place Jules Janssen, 92190 Meudon, France Bożena Czerny N. Copernicus Astronomical Centre, Bartycka 18, 00-716 Warsaw, Poland Keywords: quasars, Active Galactic Nuclei, Black holes, galaxies, evolution Content 1. Historical aspects 1.1. Prehistory 1.2. After the Discovery of Quasars 1.3. Accretion Onto Supermassive Black Holes: Why It Works So Well? 2. The emission properties of radio-quiet quasars and AGN 2.1. The Broad Band Spectrum: The “Accretion Emission" 2.2. Optical, Ultraviolet, and X-Ray Emission Lines 2.3. Ultraviolet and X-Ray Absorption Lines: The Wind 2.4. Variability 3. Related objects and Unification Scheme 3.1. The “zoo" of AGN 3.2. The “Line of View" Unification: Radio Galaxies and Radio-Loud Quasars, Blazars, Seyfert 1 and 2 3.2.1. Radio Loud Quasars and AGN: The Jet and the Gamma Ray Emission 3.3. Towards Unification of Radio-Loud and Radio-Quiet Objects? 3.4. The “Accretion Rate" Unification: Low and High Luminosity AGN 4. Evolution of black holes 4.1. Supermassive Black Holes in Quasars and AGN 4.2. Supermassive Black Holes in Quiescent Galaxies 5. Linking the growth of black holes to galaxy evolution 6. Conclusions Acknowledgements GlossaryUNESCO – EOLSS Bibliography Biographical Sketches SAMPLE CHAPTERS Summary We recall the discovery of quasars and the long time it took (about 15 years) to build a theoretical framework for these objects, as well as for their local less luminous counterparts, Active Galactic Nuclei (AGN). -
190 Index of Names
Index of names Ancora Leonis 389 NGC 3664, Arp 005 Andriscus Centauri 879 IC 3290 Anemodes Ceti 85 NGC 0864 Name CMG Identification Angelica Canum Venaticorum 659 NGC 5377 Accola Leonis 367 NGC 3489 Angulatus Ursae Majoris 247 NGC 2654 Acer Leonis 411 NGC 3832 Angulosus Virginis 450 NGC 4123, Mrk 1466 Acritobrachius Camelopardalis 833 IC 0356, Arp 213 Angusticlavia Ceti 102 NGC 1032 Actenista Apodis 891 IC 4633 Anomalus Piscis 804 NGC 7603, Arp 092, Mrk 0530 Actuosus Arietis 95 NGC 0972 Ansatus Antliae 303 NGC 3084 Aculeatus Canum Venaticorum 460 NGC 4183 Antarctica Mensae 865 IC 2051 Aculeus Piscium 9 NGC 0100 Antenna Australis Corvi 437 NGC 4039, Caldwell 61, Antennae, Arp 244 Acutifolium Canum Venaticorum 650 NGC 5297 Antenna Borealis Corvi 436 NGC 4038, Caldwell 60, Antennae, Arp 244 Adelus Ursae Majoris 668 NGC 5473 Anthemodes Cassiopeiae 34 NGC 0278 Adversus Comae Berenices 484 NGC 4298 Anticampe Centauri 550 NGC 4622 Aeluropus Lyncis 231 NGC 2445, Arp 143 Antirrhopus Virginis 532 NGC 4550 Aeola Canum Venaticorum 469 NGC 4220 Anulifera Carinae 226 NGC 2381 Aequanimus Draconis 705 NGC 5905 Anulus Grahamianus Volantis 955 ESO 034-IG011, AM0644-741, Graham's Ring Aequilibrata Eridani 122 NGC 1172 Aphenges Virginis 654 NGC 5334, IC 4338 Affinis Canum Venaticorum 449 NGC 4111 Apostrophus Fornac 159 NGC 1406 Agiton Aquarii 812 NGC 7721 Aquilops Gruis 911 IC 5267 Aglaea Comae Berenices 489 NGC 4314 Araneosus Camelopardalis 223 NGC 2336 Agrius Virginis 975 MCG -01-30-033, Arp 248, Wild's Triplet Aratrum Leonis 323 NGC 3239, Arp 263 Ahenea -
Unlocking Galactic Wolf-Rayet Stars with $\Textit {Gaia} $ DR2 II: Cluster
MNRAS 000,1{19 (2019) Preprint 7 May 2020 Compiled using MNRAS LATEX style file v3.0 Unlocking Galactic Wolf-Rayet stars with Gaia DR2 II: Cluster and Association membership Gemma Rate,? Paul A. Crowther, Richard J. Parkery Department of Physics and Astronomy, University of Sheffield, Sheffield, S3 7RH, UK Accepted XXX. Received YYY; in original form ZZZ ABSTRACT Galactic Wolf-Rayet (WR) star membership of star forming regions can be used to constrain the formation environments of massive stars. Here, we utilise Gaia DR2 parallaxes and proper motions to reconsider WR star membership of clusters and associations in the Galactic disk, supplemented by recent near-IR studies of young massive clusters. We find that only 18{36% of 553 WR stars external to the Galac- tic Centre region are located in clusters, OB associations or obscured star-forming regions, such that at least 64% of the known disk WR population are isolated, in contrast with only 13% of O stars from the Galactic O star Catalogue. The fraction located in clusters, OB associations or star-forming regions rises to 25{41% from a global census of 663 WR stars including the Galactic Centre region. We use simu- lations to explore the formation processes of isolated WR stars. Neither runaways, nor low mass clusters, are numerous enough to account for the low cluster member- ship fraction. Rapid cluster dissolution is excluded as mass segregation ensures WR stars remain in dense, well populated environments. Only low density environments consistently produce WR stars that appeared to be isolated during the WR phase. -
Atlante Grafico Delle Galassie
ASTRONOMIA Il mondo delle galassie, da Kant a skylive.it. LA RIVISTA DELL’UNIONE ASTROFILI ITALIANI Questo è un numero speciale. Viene qui presentato, in edizione ampliata, quan- [email protected] to fu pubblicato per opera degli Autori nove anni fa, ma in modo frammentario n. 1 gennaio - febbraio 2007 e comunque oggigiorno di assai difficile reperimento. Praticamente tutte le galassie fino alla 13ª magnitudine trovano posto in questo atlante di più di Proprietà ed editore Unione Astrofili Italiani 1400 oggetti. La lettura dell’Atlante delle Galassie deve essere fatto nella sua Direttore responsabile prospettiva storica. Nella lunga introduzione del Prof. Vincenzo Croce il testo Franco Foresta Martin Comitato di redazione e le fotografie rimandano a 200 anni di studio e di osservazione del mondo Consiglio Direttivo UAI delle galassie. In queste pagine si ripercorre il lungo e paziente cammino ini- Coordinatore Editoriale ziato con i modelli di Herschel fino ad arrivare a quelli di Shapley della Via Giorgio Bianciardi Lattea, con l’apertura al mondo multiforme delle altre galassie, iconografate Impaginazione e stampa dai disegni di Lassell fino ad arrivare alle fotografie ottenute dai colossi della Impaginazione Grafica SMAA srl - Stampa Tipolitografia Editoria DBS s.n.c., 32030 metà del ‘900, Mount Wilson e Palomar. Vecchie fotografie in bianco e nero Rasai di Seren del Grappa (BL) che permettono al lettore di ripercorrere l’alba della conoscenza di questo Servizio arretrati primo abbozzo di un Universo sempre più sconfinato e composito. Al mondo Una copia Euro 5.00 professionale si associò quanto prima il mondo amatoriale. Chi non è troppo Almanacco Euro 8.00 giovane ricorderà le immagini ottenute dal cielo sopra Bologna da Sassi, Vac- Versare l’importo come spiegato qui sotto specificando la causale.