Earth and Space Sciences Annual Report 2015 Dear Reader
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
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 .................................. -
Probing the High-Redshift Universe with SPICA: Toward the Epoch of Reionization and Beyond
Publications of the Astronomical Society of Australia (PASA) doi: 10.1017/pas.2018.xxx. Probing the High-Redshift Universe with SPICA: Toward the Epoch of Reionization and Beyond E. Egami1, S. Gallerani2, R. Schneider3, A. Pallottini2,4,5,6, L. Vallini7, E. Sobacchi2, A. Ferrara2, S. Bianchi8, M. Bocchio8, S. Marassi9, L. Armus10, L. Spinoglio11, A. W. Blain12, M. Bradford13, D. L. Clements14, H. Dannerbauer15,16, J. A. Fernández-Ontiveros11,15,16, E. González-Alfonso17, M. J. Griffin18, C. Gruppioni19, H. Kaneda20, K. Kohno21, S. C. Madden22, H. Matsuhara23, P. Najarro24, T. Nakagawa23, S. Oliver25, K. Omukai26, T. Onaka27, C. Pearson28, I. Perez- Fournon15,16, P. G. Pérez-González29, D. Schaerer30, D. Scott31, S. Serjeant32, J. D. Smith33, F. F. S. van der Tak34,35, T. Wada24, and H. Yajima36 1Steward Observatory, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721, USA 2Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126, Pisa, Italy 3Dipartimento di Fisica “G. Marconi”, Sapienza Universitá di Roma, P.le A. Moro 2, 00185 Roma, Italy 4Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK 5Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Ave., Cambridge CB3 0HE, UK 6Centro Fermi, Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, Piazza del Viminale 1, Roma, 00184, Italy 7Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA Leiden, The Netherlands 8INAF, Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy 9INAF, Osservatorio -
Information Bulletin on Variable Stars
COMMISSIONS AND OF THE I A U INFORMATION BULLETIN ON VARIABLE STARS Nos November July EDITORS L SZABADOS K OLAH TECHNICAL EDITOR A HOLL TYPESETTING K ORI ADMINISTRATION Zs KOVARI EDITORIAL BOARD L A BALONA M BREGER E BUDDING M deGROOT E GUINAN D S HALL P HARMANEC M JERZYKIEWICZ K C LEUNG M RODONO N N SAMUS J SMAK C STERKEN Chair H BUDAPEST XI I Box HUNGARY URL httpwwwkonkolyhuIBVSIBVShtml HU ISSN COPYRIGHT NOTICE IBVS is published on b ehalf of the th and nd Commissions of the IAU by the Konkoly Observatory Budap est Hungary Individual issues could b e downloaded for scientic and educational purp oses free of charge Bibliographic information of the recent issues could b e entered to indexing sys tems No IBVS issues may b e stored in a public retrieval system in any form or by any means electronic or otherwise without the prior written p ermission of the publishers Prior written p ermission of the publishers is required for entering IBVS issues to an electronic indexing or bibliographic system to o CONTENTS C STERKEN A JONES B VOS I ZEGELAAR AM van GENDEREN M de GROOT On the Cyclicity of the S Dor Phases in AG Carinae ::::::::::::::::::::::::::::::::::::::::::::::::::: : J BOROVICKA L SAROUNOVA The Period and Lightcurve of NSV ::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::: W LILLER AF JONES A New Very Long Period Variable Star in Norma ::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::::: EA KARITSKAYA VP GORANSKIJ Unusual Fading of V Cygni Cyg X in Early November ::::::::::::::::::::::::::::::::::::::: -
Morphology and Kinematics of the Gas Envelope of the Mira Binary W Aquilae 3
Research in Astron. Astrophys. Vol.0 (200x) No.0, 000–000 Research in http://www.raa-journal.org http://www.iop.org/journals/raa Astronomy and Astrophysics Morphology and kinematics of the gas envelope of the Mira binary W Aquilae ⋆ D. T. Hoai, P. T. Nhung, P. N. Diep, N. T. Phuong, P. Tuan-Anh, N. T. Thao and P. Darriulat Department of Astrophysics, Vietnam National Satellite Center, VAST, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam; [email protected] Abstract We analyse ALMA observations of the 12CO(3-2) emission of the circumstellar envelope (CSE) of the Mira variable binary star W Aql. These provide, for the first time, spatially resolved Doppler velocity spectra of the CSE up to angular distances to the central star of ∼ 5′′ (meaning some 2000 AU). The exploratory nature of the observations (only five minutes in each of two different configurations) does not allow for a detailed modelling of the properties of the CSE but provides important qualitative information on its morphology and kinematics. Emission is found to be enhanced along an axis moving from east/west to north-east/south-west when the angular distance from the central star projected on the plane of the sky increases from zero to four arcseconds. In parallel, the Doppler velocity distribution displays asymmetry along an axis moving from east/west to north-west/south-east. The results are discussed in the context of earlier observations, in particular of the dust morphology. Key words: stars: AGB and post-AGB − (Star:) circumstellar matter − Star: individual (W Aql) − Stars: mass-loss − radio lines: stars. -
Agrarian Metaphors 397
396 Agrarian Metaphors 397 The Bible provided homilists with a rich store of "agricultural" metaphors and symbols) The loci classici are passages like Isaiah's "Song of the Vineyard" (Is. 5:1-7), Ezekiel's allegories of the Tree (Ez. 15,17,19:10-14,31) and christ's parables of the Sower (Matt. 13: 3-23, Mark 4:3-20, Luke 8:5-15) ,2 the Good Seed (Matt. 13:24-30, Mark 4:26-29) , the Barren Fig-tree (Luke 13:6-9) , the Labourers in the Vineyard (Matt. 21:33-44, Mark 12:1-11, Luke 20:9-18), and the Mustard Seed (Matt. 13:31-32, Mark 4:30-32, Luke 13:18-19). Commonplace in Scripture, however, are comparisons of God to a gardener or farmer,5 6 of man to a plant or tree, of his soul to a garden, 7and of his works to "fruits of the spirit". 8 Man is called the "husbandry" of God (1 Cor. 3:6-9), and the final doom which awaits him is depicted as a harvest in which the wheat of the blessed will be gathered into God's storehouse and the chaff of the damned cast into eternal fire. Medieval scriptural commentaries and spiritual handbooks helped to standardize the interpretation of such figures and to impress them on the memories of preachers (and their congregations). The allegorical exposition of the res rustica presented in Rabanus Maurus' De Universo (XIX, cap.l, "De cultura agrorum") is a distillation of typical readings: Spiritaliter ... in Scripturis sacris agricultura corda credentium intelliguntur, in quibus fructus virtutuxn germinant: unde Apostolus ad credentes ait [1 Cor. -
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. -
Molecular Line Study of the S-Type AGB Star W Aquilae ALMA Observations of CS, Sis, Sio and HCN
Astronomy & Astrophysics manuscript no. WAql-v6-revision_02_final c ESO 2018 October 5, 2018 Molecular line study of the S-type AGB star W Aquilae ALMA observations of CS, SiS, SiO and HCN M. Brunner1, T. Danilovich2; 3, S. Ramstedt4, I. Marti-Vidal2, E. De Beck2, W.H.T. Vlemmings2, M. Lindqvist2, and F. Kerschbaum1 1 Department for Astrophysics, University of Vienna, Türkenschanzstrasse 17, A-1180 Vienna e-mail: [email protected] 2 Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden 3 Department of Physics and Astronomy, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium 4 Department of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden Received Month nr, YYYY; accepted Month nr, YYYY ABSTRACT Context. With the outstanding spatial resolution and sensitivity of the Atacama Large Millimeter/sub-millimeter Array (ALMA), molecular gas other than the abundant CO can be observed and resolved in circumstellar envelopes (CSEs) around evolved stars, such as the binary S-type Asymptotic Giant Branch (AGB) star W Aquilae. Aims. We aim to constrain the chemical composition of the CSE and determine the radial abundance distribution, the photospheric peak abundance, and isotopic ratios of a selection of chemically important molecular species in the innermost CSE of W Aql. The derived parameters are put into the context of the chemical evolution of AGB stars and are compared with theoretical models. Methods. We employ one-dimensional radiative transfer modeling – with the accelerated lambda iteration (ALI) radiative transfer code – of the radial abundance distribution of a total of five molecular species (CS, SiS, 30SiS, 29SiO and H13CN) and determine the best fitting model parameters based on high-resolution ALMA observations as well as archival single-dish observations. -
OPTICAL IMAGING of VERY LUMINOUS INFRARED GALAXY SYSTEMS: PHOTOMETRIC PROPERTIES and LATE EVOLUTION Santiago Arribas,1,2 Howard Bushouse, and Ray A
The Astronomical Journal, 127:2522–2543, 2004 May # 2004. The American Astronomical Society. All rights reserved. Printed in U.S.A. OPTICAL IMAGING OF VERY LUMINOUS INFRARED GALAXY SYSTEMS: PHOTOMETRIC PROPERTIES AND LATE EVOLUTION Santiago Arribas,1,2 Howard Bushouse, and Ray A. Lucas Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218; [email protected], [email protected], [email protected] Luis Colina Instituto de Estructura de la Materia, CSIC, Serrano 119, E-28006 Madrid, Spain; [email protected] and Kirk D. Borne George Mason University, School of Computational Sciences; and NASA Goddard Space Flight Center, Greenbelt, MD 20771; [email protected] Received 2003 November 7; accepted 2004 February 17 ABSTRACT 11 A sample of 19 low-redshift (0:03 < z < 0:07), very luminous infrared galaxy [VLIRG: 10 L < L(8– 12 1000 m) < 10 L ] systems (30 galaxies) has been imaged in B, V,andI using ALFOSC with the Nordic Optical Telescope. These objects cover a luminosity range that is key to linking the most luminous infrared galaxies with the population of galaxies at large. As previous morphological studies have reported, most of these objects exhibit features similar to those found in ultraluminous infrared galaxies (ULIRGs), which suggests that they are also undergoing strong interactions or mergers. We have obtained photometry for all of these VLIRG systems, the individual galaxies (when detached), and their nuclei, and the relative behavior of these classes has been studied in optical color-magnitude diagrams. The observed colors and magnitudes for both the systems and the nuclei lie parallel to the reddening vector, with most of the nuclei having redder colors than the galaxy disks. -
An ISOCAM Survey Through Gravitationally Lensing Galaxy Clusters. IV
Astronomy & Astrophysics manuscript no. 1782ms October 30, 20181 (DOI: will be inserted by hand later) An ISOCAM survey through gravitationally lensing galaxy clusters. ⋆ IV. Luminous infrared galaxies in Cl 0024+1654 and the dynamical status of clusters D. Coia1, B. McBreen1, L. Metcalfe2,3, A. Biviano4, B. Altieri2, S. Ott5, B. Fort6, J.-P. Kneib7,8, Y. Mellier6,9, M.-A. Miville-Deschˆenes10 , B. O’Halloran1,11, and C. Sanchez-Fernandez2 . 1 Department of Experimental Physics, University College, Belfield, Dublin 4, Ireland. 2 XMM-Newton Science Operations Centre, European Space Agency, Villafranca del Castillo, P.O. Box 50727, 28080 Madrid, Spain. 3 ISO Data Centre, European Space Agency, Villafranca del Castillo, P.O. Box 50727, 28080 Madrid, Spain. 4 INAF/Osservatorio Astronomico di Trieste, via G.B. Tiepolo 11, 34131, Trieste, Italy. 5 Science Operations and Data Systems Division of ESA, ESTEC, Keplerlaan 1, 2200 AG Noordwijk, The Netherlands. 6 Institut d’Astrophysique de Paris, 98 bis boulevard Arago, 75014 Paris, France. 7 Observatoire Midi-Pyr´en´ees, 14 avenue Edouard Belin, 31400 Toulouse, France. 8 California Institute of Technology, Pasadena, CA 91125, USA. 9 Observatoire de Paris, 61 avenue de l’Observatoire, 75014 Paris, France. 10 Canadian Institute for Theoretical Astrophysics, 60 St-George Street, Toronto, Ontario, M5S 3H8, Canada. 11 Dunsink Observatory, Castleknock, Dublin 15, Ireland. Received 30 July 2003 / Accepted 26 October 2004 Abstract. Observations of the core of the massive cluster Cl 0024+1654, at a redshift z ∼ 0.39, were obtained with the Infrared Space Observatory using ISOCAM at 6.7 µm (hereafter 7 µm) and 14.3 µm (hereafter 15 µm). -
The Radio Core Structure of the Luminous Infrared Galaxy NGC 4418 a Young Clustered Starburst Revealed? E
A&A 566, A15 (2014) Astronomy DOI: 10.1051/0004-6361/201323303 & c ESO 2014 Astrophysics The radio core structure of the luminous infrared galaxy NGC 4418 A young clustered starburst revealed? E. Varenius1,J.E.Conway1, I. Martí-Vidal1, S. Aalto1, R. Beswick2, F. Costagliola3, and H.-R. Klöckner4 1 Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden e-mail: [email protected] 2 Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK 3 Instituto de Astrofísica de Andalucía, Glorieta de la Astronomá, s/n, 18008 Granada, Spain 4 Max-Planck-Institut für Radioastronomie, auf dem Hügel 69, 53121 Bonn, Germany Received 20 December 2013 / Accepted 13 February 2014 ABSTRACT Context. The galaxy NGC 4418 contains one of the most compact obscured nuclei within a luminous infrared galaxy (LIRG) in the nearby Universe. This nucleus contains a rich molecular gas environment and an unusually high ratio of infrared-to-radio luminosity (q-factor). The compact nucleus is powered by either a compact starburst or an active galactic nucleus (AGN). Aims. The aim of this study is to constrain the nature of the nuclear region (starburst or AGN) within NGC 4418 via very-high- resolution radio imaging. Methods. Archival data from radio observations using the European Very Long Baseline Interferometry Network (EVN) and Multi- Element Radio Linked Interferometer Network (MERLIN) interferometers are imaged. Sizes and flux densities are obtained by fitting Gaussian intensity distributions to the image. The average spectral index of the compact radio emission is estimated from measurements at 1.4 GHz and 5.0 GHz. -
International Astronomical Union Commission G1 BIBLIOGRAPHY
International Astronomical Union Commission G1 BIBLIOGRAPHY OF CLOSE BINARIES No. 108 Editor-in-Chief: W. Van Hamme Editors: R.H. Barb´a D.R. Faulkner P.G. Niarchos D. Nogami R.G. Samec C.D. Scarfe C.A. Tout M. Wolf M. Zejda Material published by March 15, 2019 BCB issues are available at the following URLs: http://ad.usno.navy.mil/wds/bsl/G1_bcb_page.html, http://faculty.fiu.edu/~vanhamme/IAU-BCB/. The bibliographical entries for Individual Stars and Collections of Data, as well as a few General entries, are categorized according to the following coding scheme. Data from archives or databases, or previously published, are identified with an asterisk. The observation codes in the first four groups may be followed by one of the following wavelength codes. g. γ-ray. i. infrared. m. microwave. o. optical r. radio u. ultraviolet x. x-ray 1. Photometric data a. CCD b. Photoelectric c. Photographic d. Visual 2. Spectroscopic data a. Radial velocities b. Spectral classification c. Line identification d. Spectrophotometry 3. Polarimetry a. Broad-band b. Spectropolarimetry 4. Astrometry a. Positions and proper motions b. Relative positions only c. Interferometry 5. Derived results a. Times of minima b. New or improved ephemeris, period variations c. Parameters derivable from light curves d. Elements derivable from velocity curves e. Absolute dimensions, masses f. Apsidal motion and structure constants g. Physical properties of stellar atmospheres h. Chemical abundances i. Accretion disks and accretion phenomena j. Mass loss and mass exchange k. Rotational velocities 6. Catalogues, discoveries, charts a. Catalogues b. Discoveries of new binaries and novae c. -
An Analysis of the Environment and Gas Content of Luminous Infrared Galaxies
Abstract Title of Dissertation: An Analysis of the Environment and Gas Content of Luminous Infrared Galaxies Bevin Ashley Zauderer, Doctor of Philosophy, 2010 Dissertation directed by: Professor Stuart N. Vogel Department of Astronomy Luminous and ultraluminous infrared galaxies (U/LIRGs) represent a population among the most extreme in our universe, emitting an extraordinary amount of energy at infrared wavelengths from dust heated by prolific star formation and/or an active galactic nucleus (AGN). We present three investigations of U/LIRGs to better understand their global environment, their interstellar medium properties, and their nuclear region where molecular gas feeds a starburst or AGN. To study the global environment, we compute the spatial cluster-galaxy amplitude, Bgc, for 76 z < 0.3 ULIRGs. We find the environment of ULIRGs is similar to galaxies in the field. Comparing our results with other galactic populations, we conclude that ULIRGs might be a phase in the lives of AGNs and QSOs, but not all moderate-luminosity QSOs necessarily pass through a ULIRG phase. To study the interstellar medium properties, we observe H I and other spectral lines in 77 U/LIRGs with the Arecibo telescope. We detect H I in emission or absorption in 61 of 77 galaxies, 52 being new detections. We compute the implied gas mass for galaxies with emission, and optical depths and column densities for the seven sources with absorption detections. To study the molecular gas in the nuclear region of LIRG Arp 193, sub-arcsecond scale angular resolution is required and a method of atmospheric phase correction imperative. We present results of a large experiment observing bright quasars to test the limitations of the Combined Array for Research in Millimeter Astronomy’s Paired Antenna Calibration System (C-PACS) for atmospheric phase correction.