The Discovery of Quasars
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Velocity Structure of the Orion a Integral Shaped Filament (La Estructura De La Velocidad Del Filamento Integral Shaped Filament De Orion´ A)
Universidad de Concepcion´ Departamento de Astronom´ıa Facultad de Ciencias F´ısicas y Matematicas´ Velocity structure of the Orion A Integral Shaped Filament (La estructura de la velocidad del filamento Integral Shaped Filament de Orion´ A) Tesis para ser presentada en la direccion´ de postgrado de la Universidad de Concepcion´ para optar al grado de Magister en ciencias con mencion´ en f´ısica Valentina Isabel Gonzalez´ Lobos Asesor: Prof. Amelia Stutz Concepcion,´ Chile Junio 2019 Agradecimientos Quiero agradecer todes quienes que me apoyaron durante todo este periodo. A quienes lo hicieron desde el comienzo y a quienes llegaron durante el camino. A mis amigues y compa~neresque hicieron del proceso m´asalegre. A mi pololo y familia que me levantaron cuando lo necesit´e.A aquellos profesores que mostraron su apoyo y me hicieron creer m´asen mi misma. Finalmente, agradezco a Dominik Schleicher, al programa Basal y a CONICYT por el apoyo econ´omico. ii Resumen El proceso de formaci´onestelar es fundamental para comprender la formaci´onde planetas y la evoluci´onde galaxias. Casi todas las estrellas se forman en c´umulos estelares que son contenidos en filamentos masivos. Aqu´ıpresentamos un an´alisisde la cinem´aticadel gas del filamento Inte- gral Shaped Filament en Ori´onA utilizando observaciones de distintas transiciones moleculares 12 13 + ( CO, CO, NH3,N2H ) para rastrear el gas a distintas densidades. Describimos la estructura de la velocidad a lo largo del filamento a trav´esde diagramas de posici´on-velocidad ponderado por la intensidad o lo comparamos con la distribuci´onde la masa del gas y las estrellas. -
General Disclaimer One Or More of the Following Statements May Affect
General Disclaimer One or more of the Following Statements may affect this Document This document has been reproduced from the best copy furnished by the organizational source. It is being released in the interest of making available as much information as possible. This document may contain data, which exceeds the sheet parameters. It was furnished in this condition by the organizational source and is the best copy available. This document may contain tone-on-tone or color graphs, charts and/or pictures, which have been reproduced in black and white. This document is paginated as submitted by the original source. Portions of this document are not fully legible due to the historical nature of some of the material. However, it is the best reproduction available from the original submission. Produced by the NASA Center for Aerospace Information (CASI) r 40^4 ^I I d 9 , GPL' , 1TIONAL-WAVE BURSTS FROM THE NUCLEI OF DISTANT GALAXLFS AND QUASARS: *+ PRGPOSAL FOR DETECTION USING DOPPLER TRACKING OF INTERPLANETARY SPACECRAFT KIP S. THORNE Californi,% Ints_itute of Technology, Pasadena, California, U.S.A. and VLADIMIR B. BRAGINSKY 1 1 hystcs Faculty, Moscow State University, Moscow, U.S.S.R. (NASA-CR-145432) GRAVITATIONAL-WAVE BURSTS N76-10977 FROM THE NUCLEI OF DISTANT GALLXIES AND QUASARS: PROPOSAL FOR DETECTION USING 6 J^ DOPPLER TRACKING OF INTERPLANETARY Unclas SPACFCRAFT (California Inst. of Tech.) 17 p G3/93 39447 R p v19 5 Nq4 41 Supported in part by the Ministry of Higher Education, U.S.S.R.; and by the National Aeronau and Space Administration [NCR-05-002-2561 and the National Science Foundation [MPS75-013981, U.S.A. -
Molecular Clouds in the Milky Way
AA53CH15-Heyer ARI 27 July 2015 8:17 Molecular Clouds in the Milky Way Mark Heyer1 and T.M. Dame2 1Department of Astronomy, University of Massachusetts, Amherst, Massachusetts 01003; email: [email protected] 2Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138; email: [email protected] Annu. Rev. Astron. Astrophys. 2015. 53:583–629 Keywords The Annual Review of Astronomy and Astrophysics is Galaxy: disk, structure; ISM: clouds, kinematics and dynamics, molecules; online at astro.annualreviews.org radio lines: ISM This article’s doi: 10.1146/annurev-astro-082214-122324 Abstract Copyright c 2015 by Annual Reviews. In the past twenty years, the reconnaissance of 12CO and 13CO emission All rights reserved in the Milky Way by single-dish millimeter-wave telescopes has expanded our view and understanding of interstellar molecular gas. We enumerate the major surveys of CO emission along the Galactic plane and summarize the various approaches that leverage these data to determine the large-scale distribution of molecular gas: its radial and vertical distributions, its concen- tration into clouds, and its relationship to spiral structure. The integrated Annu. Rev. Astron. Astrophys. 2015.53:583-629. Downloaded from www.annualreviews.org properties of molecular clouds are compiled from catalogs derived from the CO surveys using uniform assumptions regarding the Galactic rotation Access provided by State University of New York - Stony Brook on 08/28/17. For personal use only. curve, solar radius, and the CO-to-H2 conversion factor. We discuss the ra- dial variations of cloud surface brightness, the distributions of cloud mass and size, and scaling relations between velocity dispersion, cloud size, and surface density that affirm that the larger clouds are gravitationally bound. -
Ay 21 - Galaxies and Cosmology Prof
Ay 21 - Galaxies and Cosmology Prof. S. G. Djorgovski Winter 2021 Cosmology* as a Science • A study of the universe as a whole, its global geometry, dynamics, history, fate, and its major constituents - galaxies and large-scale structures, their formation and evolution • A basic assumption: the physical laws are the same at all times and everywhere – Some aspects of this are testable – But a new and unexpected physics can show up, e.g., dark matter, dark energy • Only one object of study, and all we can do is look at the surface of the past light cone • Observations tend to be difficult, and subject to biases and selection effects * From Greek kosmos = order; see also cosmetology … The Evolution of the Cosmological Thought … From magical and arbitrary to rational and scientific Folklore to theology to philosophy to physics … Away from anthropocentric/anthropomorphic The Copernican revolution … From final and static to evolving and open-ended The Darwinian revolution … From absolute certainty to an ever expanding sphere of knowledge and a boundary of unknown Cosmology today is a branch of physics Dust Off Your Astronomical Units! • Distance: – Astronomical unit: the distance from the Earth to the Sun, 1 au = 1.496Í1013 cm – Light year: c Í1 yr, 1 ly = 9.463 Í1017 cm – Parsec: the distance from which 1 au subtends an angle of 1 arcsec, 1 pc = 3.086 Í1018 cm = 3.26 ly = 206,264.8 au • Mass and Luminosity: 33 – Solar mass: 1 M = 1.989 Í10 g 33 – Solar luminosity: 1 L = 3.826Í10 erg/s Fluxes and Magnitudes For historical reasons, fluxes in the optical and IR are measured in magnitudes: m = −2.5log10 F + constant Usually integrated over some finite bandpass, e.g., V band (l ~ 550 nm): € fl mV = −2.5log10 F + constant flux integrated over the range l of wavelengths for this band € If the flux is integrated over the entire spectrum, then m is the bolometric magnitude. -
Honors and Awards Schmidt Wins Kavli Prize
Maarten Schmidt (left) and Donald Lynden-Bell (center) receive the Kavli Prize from Crown Prince Haakon Mag- nus in Stockholm. FACULTY FILE SCHMIDT WINS must be emitting hundreds of times HONORS AND more energy than the 10 billion stars KAVLI PRIZE of the Milky Way. Later, researchers AWARDS Maarten Schmidt, the Moseley learned that this glut of energy spews R&D magazine has honored the work Professor of Astronomy, Emeritus, from a volume of space no larger than of Liepmann Professor of Aeronau- has been awarded the $1 million the size of our own solar system. It tics and professor of bioengineering Kavli Prize for his contributions in was Lynden-Bell who suggested that Morteza Gharib (PhD ’83) and his astrophysics. He is one of the seven a supermassive black hole feasting team, including Emilio Graff (PhD first recipients of the prize, and shares on matter at the center of distant ’07) and postdoctoral fellow Francis- the astrophysics award with Donald galaxies was generating the prodi- co Pereira with the R&D 100 Award. Lynden-Bell, of Cambridge Univer- gious amounts of energy. And after The group designed a camera that sity, who was a Caltech postdoc from studying the evolution and distribution creates a three-dimensional image by 1961 to 1962. of quasars, Schmidt discovered that extracting information from a series Schmidt and Lynden-Bell are quasars were more abundant when of images. The researchers say the known for discovering that quasars the universe was younger. camera has a myriad of applications, are galaxies harboring supermas- “I’m delighted with the award. -
Interview with Maarten Schmidt
MAARTEN SCHMIDT (b. 1929) INTERVIEWED BY TIMOTHY D. MOY January 21 & February 5, 1992 Maarten, Schmidt, 1991 ARCHIVES CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California Preface to the Keck Series Interviews The interview of Maarten Schmidt (1992) was done as part of a series of 7 oral histories conducted by the Caltech Archives between 1991 and 1992 to document the early history and development of the W. M. Keck Observatory at Mauna Kea, Hawaii. They capture the observations and perspectives of administrators, astronomers, designers, and managers representing both Caltech and the University of California, who would jointly manage the project. Thanks to the support of Howard B. Keck, in 1985 the W. M. Keck Foundation donated $70 million for what would become known as Keck I. Construction began in September 1985 to build a telescope equipped with a 10-meter mirror consisting of 36 hexagonal segments that would work together to form one single reflective surface. Using only 9 of the segments, first light occurred in November 1990. By 1991, a further Keck Foundation donation made it possible to begin http://resolver.caltech.edu/CaltechOH:OH_Schmidt_M_Keck construction of Keck II—also with a 10-meter segmented mirror—with first light occurring in October 1996. Subject area Physics, astronomy, Keck Observatory Abstract An interview in two sessions, January and February 1992, with Maarten Schmidt, Francis L. Moseley Professor of Astronomy in the Division of Physics, Mathematics, and Astronomy (PMA). He recalls being brought into plans for a 10-meter telescope in 1978-1979 as director of the Hale Observatories, by Robert Sinsheimer, chancellor of UC Santa Cruz. -
The Kavli Prize Laureate Lecture
The Kavli Prize Laureate Lecture 24 April 2013, 17:00 – 20:00 The Nordic Embassies in Berlin, Rauchstraße 1, 10787 Berlin-Tiergarten In co-operation with: Berlinffff The Kavli Prize is a partnership between The Norwegian Academy of Science and Letters, The Kavli Foundation and The Norwegian Ministry of Education and Research Programme: 16:30 Registration Please be seated by 16:55 17:00 Welcome Sven E. Svedman, Norwegian Ambassador to Germany 17:05 ”The Kavli Prize: fostering scientific excellence and international cooperation” Ms Kristin Halvorsen, Norwegian Minister of Education and Research 17:20 „Internationale Herausforderungen – internationale Kooperationen: Der Auftrag der Wissenschaft“ Prof. Dr. Johanna Wanka, Federal Minister of Education and Research 17:35 Short remarks Prof. Dr. Herbert Jäckle, Vice President of the Max Planck Society 17:40 Short remarks Professor Kirsti Strøm Bull President of The Norwegian Academy of Science and Letters 17:45 Lecture: “Following the Brain’s Wires” Kavli Prize Laureate Prof. Dr. Winfried Denk Max Planck Institute for Medical Research, Heidelberg 18:10 Lecture: “Towards an Understanding of Neural Codes” Prof. Dr. Gilles Laurent Director of the Max Planck Institute for Brain Research, Frankfurt 18:35 Reception Exhibition Hall of the Nordic Embassies in Berlin “Following the Brain’s Wires” Kavli Prize Laureate Prof. Dr. Winfried Denk To understand neural circuits we need to know how neurons are connected. Over the past decade we have developed methods that allow the reconstruction of neural wiring diagrams via the acquisition and analysis of high-resolution three-dimensional electron microscopic data. We have applied these methods to the retina in order to explore, for example, how direction-selective signals are computed. -
JRP Angel and HS Stockman.“Optical and Infrared Polarization of Active
Bibliography J.R.P. Angel and H.S. Stockman. \Optical and infrared polarization of active extragalactic objects.". Ann. Rev. Astron. Astrophys., 8:321{361, 1980. S. Ant¶on and I. Browne. \Host galaxies of Flat Radio Spectrum Sources.". In L.O. Takalo and A. SillanpÄaÄa, editors, BL Lac Phenomenon, volume 159 of A.S.P. Conference Series, pages 377{380, 1999. R.R.J. Antonucci. \Polarization of active galactic nuclei and quasars". In M. Kafatos, editor, Supermassive Black Holes, Proceedings of the 3rd George Mason Astrophysics Workshop, pages 26{38. Cambridge Univer- sity Press, Cambridge, 1988. R.R.J. Antonucci and J.S. Ulvestad. \Extended radio emission and the nature of blazars.". Astrophys. J., 294:158{182, 1985. W. Baade. \Polarization in the jet of Messier 87.". Astrophys. J., 123: 550{551, 1956. J. N. Bahcall, S. Kirhakos, D. H. Saxe, and D. P. Schneider. \Hubble Space Telescope Images of a Sample of 20 Nearby Luminous Quasars". Astro- phys. J., 479:642{658, 1997. J.N. Bahcall, S. Kirhakos, D.P. Schneider, R.J. Davis, T.W.B. Muxlow, S.T. Garrington, R.G. Conway, and S.C. Unwin. \HST and MERLIN observations of the jet in 3C 273.". Astrophys. J., Lett., 452:L91{L93, 1995. R. Barvainis. \Free-free emission and the big blue bump in Active Galactic Nuclei.". Astrophys. J., 412:513{523, 1993. 152 BIBLIOGRAPHY S. A. Baum, C. P. O'Dea, G. Giovannini, J. Biretta, W. B. Cotton, S. de Ko®, L. Feretti, D. Golombek, L. Lara, F. D. Macchetto, G. K. Miley, W. B. Sparks, T. -
Science on All Scales
NEWS & VIEWS chosen collective coordinate of the atomic towards a potentially fruitful interplay of References cloud replaces the position of the end- cold-atom physics with concepts known in 1. Höhberger-Metzger, C. & Karrai, K. Nature 432, 1002–1005 (2004). 2. Gigan, S. et al. Nature 444, 67–70 (2006). mirror in the standard set-up. One of the nano- and optomechanics. Exciting avenues 3. Arcizet, O., Cohadon, P. F., Briant, T., Pinard, M. & Heidmann, A. benefits provided by this scheme is that to be explored are the role of interatomic Nature 444, 71–74 (2006). there is no need to work hard to get to the interactions (giving rise to truly collective 4. Kleckner, D. & Bouwmeester, D. Nature 444, 75–78 (2006). 5. Schliesser, A., Del’Haye, P., Nooshi, N., Vahala, K. J. ground state. In fact, in the direction along modes) and the combination with atom- & Kippenberg, T. J. Phys. Rev. Lett. 97, 243905 (2006). the cavity axis, the vibrational motion of chip techniques. 6. Corbitt, T. et al. Phys. Rev. Lett. 98, 150802 (2007). the atoms is already in the ground state, Different as the two approaches9,10 may 7. Thompson, J. D. et al. Nature 452, 72–75 (2008). 8. Schwab, K. C. & Roukes, M. L. Phys. Today 36–42 (July 2005). at microkelvin temperatures. The atoms’ be, they illustrate the rapid pace of progress 9. Regal, C. A., Teufel, J. D. & Lehnert, K. W. Nature Phys. vibrations have a rather low quality factor, in the young field of optomechanics. 4, 555–560 (2008). but this is actually useful for observing Breakthroughs such as cooling of massive 10. -
Not Yet Imagined: a Study of Hubble Space Telescope Operations
NOT YET IMAGINED A STUDY OF HUBBLE SPACE TELESCOPE OPERATIONS CHRISTOPHER GAINOR NOT YET IMAGINED NOT YET IMAGINED A STUDY OF HUBBLE SPACE TELESCOPE OPERATIONS CHRISTOPHER GAINOR National Aeronautics and Space Administration Office of Communications NASA History Division Washington, DC 20546 NASA SP-2020-4237 Library of Congress Cataloging-in-Publication Data Names: Gainor, Christopher, author. | United States. NASA History Program Office, publisher. Title: Not Yet Imagined : A study of Hubble Space Telescope Operations / Christopher Gainor. Description: Washington, DC: National Aeronautics and Space Administration, Office of Communications, NASA History Division, [2020] | Series: NASA history series ; sp-2020-4237 | Includes bibliographical references and index. | Summary: “Dr. Christopher Gainor’s Not Yet Imagined documents the history of NASA’s Hubble Space Telescope (HST) from launch in 1990 through 2020. This is considered a follow-on book to Robert W. Smith’s The Space Telescope: A Study of NASA, Science, Technology, and Politics, which recorded the development history of HST. Dr. Gainor’s book will be suitable for a general audience, while also being scholarly. Highly visible interactions among the general public, astronomers, engineers, govern- ment officials, and members of Congress about HST’s servicing missions by Space Shuttle crews is a central theme of this history book. Beyond the glare of public attention, the evolution of HST becoming a model of supranational cooperation amongst scientists is a second central theme. Third, the decision-making behind the changes in Hubble’s instrument packages on servicing missions is chronicled, along with HST’s contributions to our knowledge about our solar system, our galaxy, and our universe. -
Wallace L. W. Sargent 1935–2012
Wallace L. W. Sargent 1935–2012 A Biographical Memoir by Charles C. Steidel ©2021 National Academy of Sciences. Any opinions expressed in this memoir are those of the author and do not necessarily reflect the views of the National Academy of Sciences. WALLACE L. W. SARGENT February 15, 1935-October 29, 2012 Elected to the NAS, 2005 Wallace L. W. Sargent was the Ira S. Bowen Professor of Astronomy at the California Institute of Technology, where he was a member of the astronomy faculty for 46 years, beginning in 1966. By any measure, Sargent— known to colleagues and friends as “Wal”—was one of the most influential and consistently productive observa- tional astronomers of the last 50 years. His impact on the field of astrophysics spanned a remarkably wide range of topics and was seminal in more than a few: the primor- dial helium abundance, young galaxies, galaxy dynamics, supermassive black holes, active galactic nuclei (AGN), Technology. Institute of Photography by California and, particularly, the intergalactic medium (IGM). Wal was 77 at the time of his death in 2012; he had maintained a full complement of teaching and research until just weeks By Charles C. Steidel before succumbing to an illness he had borne quietly for more than 15 years. Generations of students, postdocs, and colleagues benefited from Wal’s rare combination of scientific taste and intuition, intellectual interests extending far beyond science, irreverent sense of humor, and genuine concern about the well-being of younger scientists. Education and Early Influences Wal was born in 1935 in Elsham, Lincolnshire, United Kingdom—a small village roughly equidistant from Sheffield and Leeds in West Lincolnshire—into a working-class family. -
Radio Galaxies Dominate the High-Energy Diffuse Gamma-Ray
FERMILAB-PUB-16-128-A Prepared for submission to JCAP Radio Galaxies Dominate the High-Energy Diffuse Gamma-Ray Background Dan Hoopera;b;c Tim Lindend and Alejandro Lopeze;a aFermi National Accelerator Laboratory, Center for Particle Astrophysics, Batavia, IL 60510 bUniversity of Chicago, Department of Astronomy and Astrophysics, Chicago, IL 60637 cUniversity of Chicago, Kavli Institute for Cosmological Physics, Chicago, IL 60637 dOhio State University, Center for Cosmology and AstroParticle Physcis (CCAPP), Colum- bus, OH 43210 eMichigan Center for Theoretical Physics, Department of Physics, University of Michigan, Ann Arbor, MI 48109 E-mail: [email protected], [email protected], [email protected] Abstract. It has been suggested that unresolved radio galaxies and radio quasars (sometimes referred to as misaligned active galactic nuclei) could be responsible for a significant fraction of the observed diffuse gamma-ray background. In this study, we use the latest data from the Fermi Gamma-Ray Space Telescope to characterize the gamma-ray emission from a sample of 51 radio galaxies. In addition to those sources that had previously been detected using Fermi data, we report here the first statistically significant detection of gamma-ray emission from the radio galaxies 3C 212, 3C 411, and B3 0309+411B. Combining this information with the radio fluxes, radio luminosity function, and redshift distribution of this source class, we +25:4 find that radio galaxies dominate the diffuse gamma-ray background, generating 77:2−9:4 % of this emission at energies above 1 GeV. We discuss the implications of this result and point out that it provides support for∼ scenarios in which IceCube's high-energy astrophysical arXiv:1604.08505v2 [astro-ph.HE] 8 Aug 2016 neutrinos also originate from the same population of radio galaxies.