The Galaxy Population Within the Virial Radius of the Perseus Cluster? H
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Astronomie in Theorie Und Praxis 8. Auflage in Zwei Bänden Erik Wischnewski
Astronomie in Theorie und Praxis 8. Auflage in zwei Bänden Erik Wischnewski Inhaltsverzeichnis 1 Beobachtungen mit bloßem Auge 37 Motivation 37 Hilfsmittel 38 Drehbare Sternkarte Bücher und Atlanten Kataloge Planetariumssoftware Elektronischer Almanach Sternkarten 39 2 Atmosphäre der Erde 49 Aufbau 49 Atmosphärische Fenster 51 Warum der Himmel blau ist? 52 Extinktion 52 Extinktionsgleichung Photometrie Refraktion 55 Szintillationsrauschen 56 Angaben zur Beobachtung 57 Durchsicht Himmelshelligkeit Luftunruhe Beispiel einer Notiz Taupunkt 59 Solar-terrestrische Beziehungen 60 Klassifizierung der Flares Korrelation zur Fleckenrelativzahl Luftleuchten 62 Polarlichter 63 Nachtleuchtende Wolken 64 Haloerscheinungen 67 Formen Häufigkeit Beobachtung Photographie Grüner Strahl 69 Zodiakallicht 71 Dämmerung 72 Definition Purpurlicht Gegendämmerung Venusgürtel Erdschattenbogen 3 Optische Teleskope 75 Fernrohrtypen 76 Refraktoren Reflektoren Fokus Optische Fehler 82 Farbfehler Kugelgestaltsfehler Bildfeldwölbung Koma Astigmatismus Verzeichnung Bildverzerrungen Helligkeitsinhomogenität Objektive 86 Linsenobjektive Spiegelobjektive Vergütung Optische Qualitätsprüfung RC-Wert RGB-Chromasietest Okulare 97 Zusatzoptiken 100 Barlow-Linse Shapley-Linse Flattener Spezialokulare Spektroskopie Herschel-Prisma Fabry-Pérot-Interferometer Vergrößerung 103 Welche Vergrößerung ist die Beste? Blickfeld 105 Lichtstärke 106 Kontrast Dämmerungszahl Auflösungsvermögen 108 Strehl-Zahl Luftunruhe (Seeing) 112 Tubusseeing Kuppelseeing Gebäudeseeing Montierungen 113 Nachführfehler -
Dwarf Galaxies: Probes for Galaxy Formation and Evolution
JD2 Dwarf Galaxies: Probes for Galaxy Formation and Evolution Chairpersons and Editors: E. Brinks &; T. X. Thuan Downloaded from https://www.cambridge.org/core. IP address: 170.106.40.139, on 30 Sep 2021 at 22:48:50, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S1539299600020074 MULTI-SPECTRAL STUDIES OF THE NEARBY DWARF GALAXIES UGCA86 AND LMC/SMC G. M. RICHTER Astrophysikalisches Institut Potsdam An der Sternwarte 16, D-14482 Potsdam, Germany gmrichter@aip. de M. BRAUN ESA-VILSPA ISOPHOT IDT Villafranca del Castillo, Satellite Tracking Station Apartado 50727, E-28080 Madrid, Spain [email protected] AND R. ASSENDORP Astrophysikalisches Institut Potsdam An der Sternwarte 16, D-14482 Potsdam, Germany rassendorp @aip. de 1. Background UGCA 86 is an irregular dwarf galaxy in the IC 342 / Maffei I group, just next to the Local Group. It was first mentioned by Zwicky (1968) as VII Zw 009, but not contained in his "Catalogue of Selected Compact Galaxies and of Post-eruptive Galaxies" (1971). It was independently rediscovered by Nilson (1974) and Rots (1979) as UGCA 86 and A 0355 resp. Rots found it by HI observations, and from peculiarities in the HI morphology and kinematics he suspected that it was interacting with IC 342. Thus, the tentatively interesting items: a starforming, low surface brightness dwarf galaxy in an interacting system (one of the nearest), triggered us to engage in more detailed studies. In a first step, we made detailed surface photometry in U, B and V (Richter et al. -
CO Multi-Line Imaging of Nearby Galaxies (COMING) IV. Overview Of
Publ. Astron. Soc. Japan (2018) 00(0), 1–33 1 doi: 10.1093/pasj/xxx000 CO Multi-line Imaging of Nearby Galaxies (COMING) IV. Overview of the Project Kazuo SORAI1, 2, 3, 4, 5, Nario KUNO4, 5, Kazuyuki MURAOKA6, Yusuke MIYAMOTO7, 8, Hiroyuki KANEKO7, Hiroyuki NAKANISHI9 , Naomasa NAKAI4, 5, 10, Kazuki YANAGITANI6 , Takahiro TANAKA4, Yuya SATO4, Dragan SALAK10, Michiko UMEI2 , Kana MOROKUMA-MATSUI7, 8, 11, 12, Naoko MATSUMOTO13, 14, Saeko UENO9, Hsi-An PAN15, Yuto NOMA10, Tsutomu, T. TAKEUCHI16 , Moe YODA16, Mayu KURODA6, Atsushi YASUDA4 , Yoshiyuki YAJIMA2 , Nagisa OI17, Shugo SHIBATA2, Masumichi SETA10, Yoshimasa WATANABE4, 5, 18, Shoichiro KITA4, Ryusei KOMATSUZAKI4 , Ayumi KAJIKAWA2, 3, Yu YASHIMA2, 3, Suchetha COORAY16 , Hiroyuki BAJI6 , Yoko SEGAWA2 , Takami TASHIRO2 , Miho TAKEDA6, Nozomi KISHIDA2 , Takuya HATAKEYAMA4 , Yuto TOMIYASU4 and Chey SAITA9 1Department of Physics, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan 2Department of Cosmosciences, Graduate School of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan 3Department of Physics, School of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan 4Division of Physics, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan 5Tomonaga Center for the History of the Universe (TCHoU), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan 6Department of Physical Science, Osaka Prefecture University, Gakuen 1-1, -
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 -
The Puzzling Nature of Dwarf-Sized Gas Poor Disk Galaxies
Dissertation submitted to the Department of Physics Combined Faculties of the Astronomy Division Natural Sciences and Mathematics University of Oulu Ruperto-Carola-University Oulu, Finland Heidelberg, Germany for the degree of Doctor of Natural Sciences Put forward by Joachim Janz born in: Heidelberg, Germany Public defense: January 25, 2013 in Oulu, Finland THE PUZZLING NATURE OF DWARF-SIZED GAS POOR DISK GALAXIES Preliminary examiners: Pekka Heinämäki Helmut Jerjen Opponent: Laura Ferrarese Joachim Janz: The puzzling nature of dwarf-sized gas poor disk galaxies, c 2012 advisors: Dr. Eija Laurikainen Dr. Thorsten Lisker Prof. Heikki Salo Oulu, 2012 ABSTRACT Early-type dwarf galaxies were originally described as elliptical feature-less galax- ies. However, later disk signatures were revealed in some of them. In fact, it is still disputed whether they follow photometric scaling relations similar to giant elliptical galaxies or whether they are rather formed in transformations of late- type galaxies induced by the galaxy cluster environment. The early-type dwarf galaxies are the most abundant galaxy type in clusters, and their low-mass make them susceptible to processes that let galaxies evolve. Therefore, they are well- suited as probes of galaxy evolution. In this thesis we explore possible relationships and evolutionary links of early- type dwarfs to other galaxy types. We observed a sample of 121 galaxies and obtained deep near-infrared images. For analyzing the morphology of these galaxies, we apply two-dimensional multicomponent fitting to the data. This is done for the first time for a large sample of early-type dwarfs. A large fraction of the galaxies is shown to have complex multicomponent structures. -
Flat Rotation Curves and Low Velocity Dispersions in KMOS Star-Forming Galaxies at Z ∼ 1? E
A&A 594, A77 (2016) Astronomy DOI: 10.1051/0004-6361/201628315 & c ESO 2016 Astrophysics Flat rotation curves and low velocity dispersions in KMOS star-forming galaxies at z ∼ 1? E. M. Di Teodoro1; 2, F. Fraternali1; 3, and S. H. Miller4 1 Department of Physics and Astronomy, University of Bologna, 6/2 Viale Berti Pichat, 40127 Bologna, Italy 2 Research School of Astronomy and Astrophysics – The Australian National University, Canberra, ACT, 2611, Australia e-mail: [email protected] 3 Kapteyn Astronomical Institute, Postbus 800, 9700 AV Groningen, The Netherlands 4 University of California – Irvine, Irvine, CA 92697, USA Received 15 February 2016 / Accepted 18 July 2016 ABSTRACT The study of the evolution of star-forming galaxies requires the determination of accurate kinematics and scaling relations out to high redshift. In this paper we select a sample of 18 galaxies at z ∼ 1; observed in the Hα emission line with KMOS, to derive accurate kinematics using a novel 3D analysis technique. We use the new code 3DBarolo, which models the galaxy emission directly in 3D observational space, without the need to extract kinematic maps. This major advantage of this technique is that it is not affected by beam smearing and thus it enables the determination of rotation velocity and intrinsic velocity dispersion, even at low spatial resolution. We find that (1) the rotation curves of these z ∼ 1 galaxies rise very steeply within few kiloparsecs and remain flat out to the outermost radius and (2) the Hα velocity dispersions are low, ranging from 15 to 40 km s−1, which leads to V/σ = 3–10. -
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. -
X-Ray and Gamma-Ray Variability of NGC 1275
galaxies Article X-ray and Gamma-ray Variability of NGC 1275 Varsha Chitnis 1,*,† , Amit Shukla 2,*,† , K. P. Singh 3 , Jayashree Roy 4 , Sudip Bhattacharyya 5, Sunil Chandra 6 and Gordon Stewart 7 1 Department of High Energy Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India 2 Discipline of Astronomy, Astrophysics and Space Engineering, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore 453552, India 3 Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Manauli 140306, India; [email protected] 4 Inter-University Centre for Astronomy and Astrophysics, Ganeshkhind, Pune 411 007, India; [email protected] 5 Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India; [email protected] 6 Centre for Space Research, North-West University, Potchefstroom 2520, South Africa; [email protected] 7 Department of Physics and Astronomy, The University of Leicester, University Road, Leicester LE1 7RH, UK; [email protected] * Correspondence: [email protected] (V.C.); [email protected] (A.S.) † These authors contributed equally to this work. Received: 30 June 2020; Accepted: 24 August 2020; Published: 28 August 2020 Abstract: Gamma-ray emission from the bright radio source 3C 84, associated with the Perseus cluster, is ascribed to the radio galaxy NGC 1275 residing at the centre of the cluster. Study of the correlated X-ray/gamma-ray emission from this active galaxy, and investigation of the possible disk-jet connection, are hampered because the X-ray emission, particularly in the soft X-ray band (2–10 keV), is overwhelmed by the cluster emission. -
Cinemática Estelar, Modelos Dinâmicos E Determinaç˜Ao De
UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL PROGRAMA DE POS´ GRADUA¸CAO~ EM F´ISICA Cinem´atica Estelar, Modelos Din^amicos e Determina¸c~ao de Massas de Buracos Negros Supermassivos Daniel Alf Drehmer Tese realizada sob orienta¸c~aoda Professora Dra. Thaisa Storchi Bergmann e apresen- tada ao Programa de P´os-Gradua¸c~aoem F´ısica do Instituto de F´ısica da UFRGS em preenchimento parcial dos requisitos para a obten¸c~aodo t´ıtulo de Doutor em Ci^encias. Porto Alegre Mar¸co, 2015 Agradecimentos Gostaria de agradecer a todas as pessoas que de alguma forma contribu´ıram para a realiza¸c~ao deste trabalho e em especial agrade¸co: • A` Profa. Dra. Thaisa Storchi-Bergmann pela competente orienta¸c~ao. • Aos professores Dr. Fabr´ıcio Ferrari da Universidade Federal do Rio Grande, Dr. Rogemar Riffel da Universidade Federal de Santa Maria e ao Dr. Michele Cappellari da Universidade de Oxford cujas colabora¸c~oes foram fundamentais para a realiza¸c~ao deste trabalho. • A todos os professores do Departamento de Astronomia do Instituto de F´ısica da Universidade Federal do Rio Grande do Sul que contribu´ıram para minha forma¸c~ao. • Ao CNPq pelo financiamento desse trabalho. • Aos meus pais Ingon e Selia e meus irm~aos Neimar e Carla pelo apoio. Daniel Alf Drehmer Universidade Federal do Rio Grande do Sul Mar¸co2015 i Resumo O foco deste trabalho ´eestudar a influ^encia de buracos negros supermassivos (BNSs) nucleares na din^amica e na cinem´atica estelar da regi~ao central das gal´axias e determinar a massa destes BNSs. -
Galactic-Scale Macro-Engineering: Looking for Signs of Other Intelligent Species, As an Exercise in Hope for Our Own
Galactic-scale macro-engineering: Looking for signs of other intelligent species, as an exercise in hope for our own * Joseph Voros Senior Lecturer in Strategic Foresight Faculty of Business & Law, Swinburne University of Technology, Melbourne, Australia Abstract If we consider Big History as simply ‘our’ example of the process of cosmic evolution playing out, then we can seek to broaden our view of our possible fate as a species by asking questions about what paths or trajectories other species’ own versions of Big History might take or have taken. This paper explores the broad outlines of possible scenarios for the evolution of long-lived intelligent engineering species—scenarios which might have been part of another species’ own Big History story, or which may yet lie ahead in our own distant future. A sufficiently long-lived engineering-oriented species may decide to undertake a program of macro-engineering projects that might eventually lead to a re-engineered galaxy so altered that its artificiality may be detectable from Earth. We consider activities that lead ultimately to a galactic structure consisting of a central inner core surrounded by a more distant ring of stars separated by a relatively sparser ‘gap’, where star systems and stellar materials may have been removed, ‘lifted’ or turned into Dyson Spheres. When one looks to the sky, one finds that such galaxies do indeed exist—including the beautiful ringed galaxy known as ‘Hoag’s Object’ (PGC 54559) in the constellation Serpens. This leads us to pose the question: Is Hoag’s Object an example of galaxy-scale macro-engineering? And this suggests a program of possible observational activities and theoretical explorations, several of which are presented here, that could be carried out in order to begin to investigate this beguiling question. -
An Outline of Stellar Astrophysics with Problems and Solutions
An Outline of Stellar Astrophysics with Problems and Solutions Using Maple R and Mathematica R Robert Roseberry 2016 1 Contents 1 Introduction 5 2 Electromagnetic Radiation 7 2.1 Specific intensity, luminosity and flux density ............7 Problem 1: luminous flux (**) . .8 Problem 2: galaxy fluxes (*) . .8 Problem 3: radiative pressure (**) . .9 2.2 Magnitude ...................................9 Problem 4: magnitude (**) . 10 2.3 Colour ..................................... 11 Problem 5: Planck{Stefan-Boltzmann{Wien{colour (***) . 13 Problem 6: Planck graph (**) . 13 Problem 7: radio and visual luminosity and brightness (***) . 14 Problem 8: Sirius (*) . 15 2.4 Emission Mechanisms: Continuum Emission ............. 15 Problem 9: Orion (***) . 17 Problem 10: synchrotron (***) . 18 Problem 11: Crab (**) . 18 2.5 Emission Mechanisms: Line Emission ................. 19 Problem 12: line spectrum (*) . 20 2.6 Interference: Line Broadening, Scattering, and Zeeman splitting 21 Problem 13: natural broadening (**) . 21 Problem 14: Doppler broadening (*) . 22 Problem 15: Thomson Cross Section (**) . 23 Problem 16: Inverse Compton scattering (***) . 24 Problem 17: normal Zeeman splitting (**) . 25 3 Measuring Distance 26 3.1 Parallax .................................... 27 Problem 18: parallax (*) . 27 3.2 Doppler shifting ............................... 27 Problem 19: supernova distance (***) . 28 3.3 Spectroscopic parallax and Main Sequence fitting .......... 28 Problem 20: Main Sequence fitting (**) . 29 3.4 Standard candles ............................... 30 Video: supernova light curve . 30 Problem 21: Cepheid distance (*) . 30 3.5 Tully-Fisher relation ............................ 31 3.6 Lyman-break galaxies and the Hubble flow .............. 33 4 Transparent Gas: Interstellar Gas Clouds and the Atmospheres and Photospheres of Stars 35 2 4.1 Transfer equation and optical depth .................. 36 Problem 22: optical depth (**) . 37 4.2 Plane-parallel atmosphere, Eddington's approximation, and limb darkening .................................. -
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).