W, a J P~V;S NATIONAL ACADEMIES of SCIENCE and ENGINEERING NATIONAL RESEARCH COUNCIL

Total Page:16

File Type:pdf, Size:1020Kb

W, a J P~V;S NATIONAL ACADEMIES of SCIENCE and ENGINEERING NATIONAL RESEARCH COUNCIL W, A j P~v;s NATIONAL ACADEMIES OF SCIENCE AND ENGINEERING NATIONAL RESEARCH COUNCIL of the UNITED STATES OF AMERICA UNITED STATES NATIONAL COMMITTEE International Union of Radio Science National Radio Science Meeting 6-9 November 1978 Sponsored by USNC/URSI in cooperation with Institute of Electrical and Electronics Engineers University of Colorado at Boulder Boulder, Colorado U.S.A. Price $5.00 --~--------~~-~-----~---- National Radio Science Meeting 6-9 November 1978 Condensed Technical Program SUNDAY, 5 NOVEMBER 2000 USNC/URSI Meeting UMC 159 MONDAY, 6 NOVEMBER 0900-1200 B-1 Scattering - I UMC West Ballroom B-2 Antenna Theory UMC Forum Room C-1 Signal Processing UMC 156 D-1 Power and Energy Measurements UMC 159 at FIR and Submillimeter Wavelengths F-1 Atmospheric Effects Above 10 GHz UMC East Ballroom 1330-1700 Combined Session UMC Center Ballroom 1715 Commission A Business Meeting UMC 158 Commission C Business Meeting UMC 156 Commission D Business Meeting UMC 159 1830-2030 Reception UMC West Ballroom and Glenn Miller Lounge TUESDAY, 7 NOVEMBER 0830-1200 A-1 Measurements and Standards UMC 158' Needs at Millimeter, Sub- Millimeter, and Far Infra- Red Frequencies B-3 New Concepts in Electromagnetics UMC West Ballroom C-2 Computer Networks UMC 156 F-2 Radiooceanography - SEASAT 1 UMC East Ballroom G-1 Ionospheric Heating Experimen- UMC Forum Room tal Results J-1 Radar Astronomy UMC 157 1330-1700 A-2 Nondestructive Electromagnetic UMC 158 Probing and Testing B-4 Earth Effects and Sommerfeld UMC West Ballroom Integral C-3 Satellite Communications UMC 156 F-3 Radiooceanography - Radar UMC East Ballroom Observations G-2 Ionospheric Behavior and UMC Forum Room Propagation J-2 Panel Discussion on UMC 157 Techniques of Very Long Baseline Interferometers 1715-1800 Commission F Business Meeting UMC East Ballroom United States N~tional Committee INTERNATIONAL UNION OF RADIO SCIENCE PROGRAM AND ABSTRACTS National Radio Science Meeting 6-9 November 1978 Sponsored by USNC/URSI in cooperation with IEEE groups and societies: Antennas and Propagation Circuits and Systems Communications Electromagnetic Compatibility Geoscience Electronics Information Theory Instrumentation and Measurement Microwave Theory and Techniques Nuclear and P~asma Sciences Quantum Electronics and Applications Hosted by: Nation.al Oceanic anc;l Atmospheric Administration National Bureau of Standards Institute for Telecommunication Sciences National Telecommunications and Information Administraticn Vniversity of Colorado at Boulder and The Denver-Boulder Chapter, IEEE/APS .,NOTE:. Programs and Abstraqts qf th.e. USNC/tiRSI }'leetings are available from: USNC/URSI Natioi:ia1 Acad,emy crE Sci~i;i.ces 2101 Constitution Ayenue, N.W. Was;hingtqn, ];i.e. ·2041,8 at $2 for meetings prior to 1970, $3 for 1971-75 meetings, and $5 for 1976-78 meetings. The full papers are not published in any collected format; requests. for , them. should b~ ~ddressed . to the. auj::hors who may have them published on their own initiative. Please note that these meetings are national c1.nd j::hey are not organized by in,t~rnational URSj:, no~ are the pr9grams available from the internationai Sec'ietariat. · · · . :_•i ii MEMBERSHIP United States National Committee INTERNATIONAL UNION OF RADIO SCIENCE Chairman: Dr. John V. Evans, Lincoln Laboratory, M.I.T.** Vice Chairman: Dr. C. Gordon Little, Environmental Researc~ Labs, NOAA#** Secretary: 'Dr. James R. Wait, Environmental Research Labs, NOAA#** Editor and Secretary Designate: Dr. Thomas B.A: Senior, University of Michigan Immediate Past Chairman: Dr. Francis S. Johnson, University of Texas, Dallas** Members Representing Societies, Groups and Institutes: American Astronomical Society Prof. Gart Westerhout American Geophysical Union Dr. Christopher T. Russel American Meteorological Society Dr. David Atlas Institute of Electrical & Dr. Ernst Weber+# Electronic Engineering IEEE Antennas & Propagation Dr. Robert C. Hansen Society IEEE Circuits & Systems Society Dr. Mohammed s. Ghausi IEEE Communications Society Mr. Amos Joel IEEE Information Theory Group Dr. Jack K. Wolf IEEE Microwave Theory & Dr. Ken J, Button Techniques IEEE Quantum Electronics Society Dr. Robert A.. Bartolini Optical Society of America Dr. Michael K. Barnoski Liaison Representatives from Government Agencies: National. Science Foundation Dr. W. Klemperper Department of Commerce vacant National Aeronautics & Dr. Erwin R. Schmerling Space Administration Federal Communications Mr. Harry Fine Commission Department of Defense Mr. Emil Paroulek Dept. of the Army Mr. Allan W. Anderson Dept. of the Navy Dr. Alan H. Schooley Dept. of the Air Force Mr. Allan C. Schell Members-At-Large: Mr. D.E. Barrick Mr. L.S. Taylor Mr. A.W. Guy iii Chairmen of the USNC-URSI Commissions: C9mmission A Dr. Raymond C. Baird Commission B Dr. Thomas A. Senior Commission C Dr. William F. Utlaut Commission D Dr, Kenneth J. Button Commission E Mr. George H. Hagn Commission F Dr. A.H. LaGrone Commission G Dr. Thomas E. Vanzandt Commission H Dr. Frederick W. Crawford Commission J Dr. K.I. Kellermann Vice Chairmen of the USNC-URSI Commissions: Commission B G.A. Deschamps# Commission C M. Schwartz Commission E A.D. Spaulding Commission F R.K. Crane Commission G J. Aarons Commission J A.T. Moffet Officers of URSI resident in the United States: (including Honorary Presidents) Vice President Prof. William E. Gordon+/** Chairmen and Vice Chairmen of Commissions of URSI resident in the United States: Chairman of Commission A Dr. Helmut M. Altschuler Chairman of Commission J Prof. Gart Westerhout Vice Chairman of Commission B Prof. Leopold B. Felsen/f Vice Chairman of Commission E Mr. George H. Hagn Vice Chairman of Commission F Prof. Alan T. Waterman, Jr. Vice Chairman of Commission H Dr. Frederick w. Crawford Foreign Secretary of the U.S. National Academy of Sciences Dr. George S. Hammond+ Chairman, Office of Physical Sciences-NRG Dr. D. Allan Bromley NRC Staff Officer Richard Y. Dow Honorary Members: Dr. Harold H. Beverage Prof. Arthur H. Waynick# + NAS Member If NAE Member ** Member of USNC-URSI Executive Committee iv DESCRIPTION OF INTERNATIONAL UNION OF RADIO SCIENCE The International Union of Radio Science is one of 17 world scientific unions organized under the International Council of Scientific Unions (ICSU). It is commonly designated as URSI (from its French name, Union Radio Scientifique Internationale). Its aims are (1) to promote the scientific study of radio communica­ tions, (2) to aid and organize radio research requiring cooperation on an international scale and to encourage the discussion and pub­ lication of the results, (3) to facilitate agreement upon common methods of measurement and the standardization of measuring instru­ ments, and (4) to stimulate and to coordinate studies of the scien­ tific aspects of telecommunications using electromagnetic waves, guided and unguided. The International Union itself is an organi­ zational framework to aid in promoting these objectives. The actual technical work is largely done by the National Committees in the various countries. The officers of the International Union are: President: J. Voge (France) Immediate Past President: Sir Granville Beynon (UK) Vice Presidents: W.N. Christiansen (Australia) W.E. Gordon (USA) V.V. Migulin (USSR) F.L.H.M. Stumpers (Netherlands) Secretary General: C.M. Minnis (Belgium) Honorary Presidents: B. Decaux (France) W. Dieminger (West Germany) J.A. Ratcliffe (UK) R.L. Smith-Rose (UK) The Secretary's office and the headquarters of the organiza­ tion are located at 7 Place Emile Danco, 1180 Brussels, Belgium. The Union is supported by contributions (dues) from 35 member countries. Additional funds for symposia and other scientific activities of the Union are provided by ICSU from contributions received for this purpose from UNESCO. The International Union, as of the XVIII General Assembly held in Helsinki, Finland, August, 1978, has nine bodies called Commissions for centralizing studies in the principal technical fields. The names of the Commissions and the chairmen follow. V A. Electromagnetic Metrology Altschuler (USA) B. Fields and Waves van Bladel (Belgium) C. Signals and Syst~ms Picinbono (France) D. Physical Electronics Smolinski (Pol~nd) E. Interference Environment Likhter (USSR) F. Wave Phenomena in Nonionized Media Eklund . (Sweden) G. Ionospheric Radio King (United Kingdom) H. Waves in Plasmas Gendrin (France) J. Radio Astronomy Westerhout (USA) Every three years., the International Union holds a meeting called the .General Assembly. The next General Assembly, the XX, will be held in Washington, D.C., in August, 1981. The Secretari­ at prepares and distribµtes the Proceedings of these General As­ semblies. The Inte.~national Union arranges international symposia on specific subjects pertaining to the work of one Commission or to several Commissions. The International Union also cooperates with other Unions in international symposia on subjects of joint interest. Radio is unique among, the fields of scientific work in having a specific adaptability to large-scale international research pro­ grams, for many of the phenomena that must be studied are world­ wide in extent and yet are .in a measure subject to control by ex­ perimenters. Exploration of space and· the ext~nsion. of scientific observations to the. space environment is dependent:· on radio for its research. One. of its branches, radio. astronomy, involves cosmos­ wide phenomena. URSI has in .all this a distinct field of useful­ ness in furnishing a meeting ground for the numerous workers in the manifold aspects of radio research; it·s meetings and committee activities furnish valuable means of promoting research through exchange of ideas. · vi NATIONAL RADIO SCIENCE MEETING COMMITTEE MEMBERS: Steering Committee: S.W. Maley, Steering Committee Chairman T.B.A. Senior, Technical Program Committee Chairman R.H. Ott, Assistant Chairman, Technical Program Committee H.A. Patterson, Registration & Facilities Committee Chairman P.L. Jensen, Publications Chairwoman s.w. Maley E.F. Kuester R.C. Baird C.G. Little H.E. Bussey R.H. OU D.C. Chang H.A. Patterson R.Y. Dow T.B.A. Senior W.L. Flock A.D. Spaulding R.L. Gallawa W.F.
Recommended publications
  • Early Stages of Massive Star Formation
    Early Stages of Massive Star Formation Vlas Sokolov Munchen¨ 2018 Early Stages of Massive Star Formation Vlas Sokolov Dissertation an der Fakultat¨ fur Physik der Ludwig–Maximilians–Universitat¨ Munchen¨ vorgelegt von Vlas Sokolov aus Kyjiw, Ukraine Munchen,¨ den 13 Juli 2018 Erstgutachter: Prof. Dr. Paola Caselli Zweitgutachter: Prof. Dr. Markus Kissler-Patig Tag der mundlichen¨ Prufung:¨ 27 August 2018 Contents Zusammenfassung xv Summary xvii 1 Introduction1 1.1 Overview......................................1 1.2 The Interstellar Medium..............................2 1.2.1 Molecular Clouds..............................5 1.3 Low-mass Star Formation..............................9 1.4 High-Mass Star and Cluster Formation....................... 12 1.4.1 Observational perspective......................... 14 1.4.2 Theoretical models............................. 16 1.4.3 IRDCs as the initial conditions of massive star formation......... 18 1.5 Methods....................................... 20 1.5.1 Radio Instrumentation........................... 20 1.5.2 Radiative Processes in the Dark Clouds.................. 22 1.5.3 Blackbody Dust Emission......................... 23 1.5.4 Ammonia inversion transitions....................... 26 1.6 This Thesis..................................... 28 2 Temperature structure and kinematics of the IRDC G035.39–00.33 31 2.1 Abstract....................................... 31 2.2 Introduction..................................... 32 2.3 Observations.................................... 33 2.3.1 GBT observations............................
    [Show full text]
  • The Galaxy in Context: Structural, Kinematic & Integrated Properties
    The Galaxy in Context: Structural, Kinematic & Integrated Properties Joss Bland-Hawthorn1, Ortwin Gerhard2 1Sydney Institute for Astronomy, School of Physics A28, University of Sydney, NSW 2006, Australia; email: [email protected] 2Max Planck Institute for extraterrestrial Physics, PO Box 1312, Giessenbachstr., 85741 Garching, Germany; email: [email protected] Annu. Rev. Astron. Astrophys. 2016. Keywords 54:529{596 Galaxy: Structural Components, Stellar Kinematics, Stellar This article's doi: 10.1146/annurev-astro-081915-023441 Populations, Dynamics, Evolution; Local Group; Cosmology Copyright c 2016 by Annual Reviews. Abstract All rights reserved Our Galaxy, the Milky Way, is a benchmark for understanding disk galaxies. It is the only galaxy whose formation history can be stud- ied using the full distribution of stars from faint dwarfs to supergiants. The oldest components provide us with unique insight into how galaxies form and evolve over billions of years. The Galaxy is a luminous (L?) barred spiral with a central box/peanut bulge, a dominant disk, and a diffuse stellar halo. Based on global properties, it falls in the sparsely populated \green valley" region of the galaxy colour-magnitude dia- arXiv:1602.07702v2 [astro-ph.GA] 5 Jan 2017 gram. Here we review the key integrated, structural and kinematic pa- rameters of the Galaxy, and point to uncertainties as well as directions for future progress. Galactic studies will continue to play a fundamen- tal role far into the future because there are measurements that can only be made in the near field and much of contemporary astrophysics depends on such observations. 529 Redshift (z) 20 10 5 2 1 0 1012 1011 ) ¯ 1010 M ( 9 r i 10 v 8 M 10 107 100 101 102 ) c p 1 k 10 ( r i v r 100 10-1 0.3 1 3 10 Time (Gyr) Figure 1 Left: The estimated growth of the Galaxy's virial mass (Mvir) and radius (rvir) from z = 20 to the present day, z = 0.
    [Show full text]
  • The Supernova Remnant W49B As Seen with H.E.S.S
    PUBLISHED VERSION H.E.S.S. Collaboration: H. Abdalla … R. Blackwell … P. DeWilt … J. Hawkes … J. Lau … N. Maxted … G. Rowell … F. Voisin … et al. The supernova remnant W49B as seen with H.E.S.S. and Fermi-LAT Astronomy and Astrophysics, 2018; 612:A5-1-A5-10 © ESO 2018 Originally published: http://dx.doi.org/10.1051/0004-6361/201527843 PERMISSIONS https://www.aanda.org/index.php?option=com_content&view=article&id=863&Itemid=2 95 Green Open Access The Publisher and A&A encourage arXiv archiving or self-archiving of the final PDF file of the article exactly as published in the journal and without any period of embargo. 19 September 208-18 http://hdl.handle.net/2440/112084 A&A 612, A5 (2018) Astronomy DOI: 10.1051/0004-6361/201527843 & c ESO 2018 Astrophysics H.E.S.S. phase-I observations of the plane of the Milky Way Special issue The supernova remnant W49B as seen with H.E.S.S. and Fermi-LAT? H.E.S.S. Collaboration: H. Abdalla1, A. Abramowski2, F. Aharonian3,4,5, F. Ait Benkhali3, A. G. Akhperjanian5; 6,y, T. Andersson10, E. O. Angüner7, M. Arrieta15, P. Aubert24, M. Backes8, A. Balzer9, M. Barnard1, Y. Becherini10, J. Becker Tjus11, D. Berge12, S. Bernhard13, K. Bernlöhr3, R. Blackwell14, M. Böttcher1, C. Boisson15, J. Bolmont16, P. Bordas3, J. Bregeon17, F. Brun26,??, P. Brun18, M. Bryan9, T. Bulik19, M. Capasso29, J. Carr20, S. Casanova21,3, M. Cerruti16, N. Chakraborty3, R. Chalme-Calvet16, R.C. G. Chaves17,22, A. Chen23, J. Chevalier24, M. Chrétien16, S.
    [Show full text]
  • Pga 183525.Pdf
    Condensed Technical Program USNC/URSI 15-19 May 1978 MONDAY, 15 MAY Room 0900-1200 B-1 Electromagnetics 0105 B-2 SEM 0109 E-1 Lightning, Spherics and Noise (Joint with F and H) 1105 1330-1700 B-3 Thin Wires 0105 B-4 Inverse Scattering and Profile Reconstruction 0109 E-2 CCIR Panel Discussion (Joint with F) 1105 F-1 Oceanography 1109 1700 Commission E Business Meeting 1105 1715 Commission B Business Meeting 0105 TUESDAY, 16 MAY 0830-1200 B-5 Scattering 0109 C-1 Impairments to Earth-Satellite Transmission 1101 F-2 Remote Sensing of the Atmosphere from Space 1109 1330-1700 B-6 Transmission Lines 0109 C-2 System Aspects of Antennas and Dual Polarization 1101 Transmission F-3 Scattering by Random Media and Rough Surfaces (Joint with 1109 AP-S and B) G-1 HF Radio Wave Absorption and Heating Effects 0123 1700 Commission C Business Meeting 1101 Commission F Business Meeting 0123 Commission H Business Meeting 0123 (continued on inside back cover) United States National Connnittee INTERNATIONAL UNION.OF RADIO SCIENCE PROGRAM AND ABSTRACTS 1978 Spring Meeting May 15-19 Held Jointly with ANTENNAS AND PROPAGATION SOCIETY INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS Washington, D.C. ]!Q:!!: Programs and Abstracts of the USNC/URSI Meetings are available from: USNC/URSI National Academy of Sciences 2101 Constitution Avenue, N.W. Washington, D.C. 20418 at $2 for meetings prior to 1970, $3 for 1971-75 meetings, and $5 for 1976-78 meetings. The full papers are not published in any collected format; requests for them should be addressed to the authors who may have them published on their own initiative.
    [Show full text]
  • VI. Dense Gas and Mini-Starbursts in the W43 Giant Molecular Cloud Complex
    Publ. Astron. Soc. Japan (2014) 00(0), 1–42 1 doi: 10.1093/pasj/xxx000 FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45 m telescope (FUGIN). VI. Dense gas and mini-starbursts in the W43 giant molecular cloud complex Mikito KOHNO1∗ ∗ , Kengo TACHIHARA1∗, Kazufumi TORII2∗, Shinji FUJITA1,3∗, Atsushi NISHIMURA1,3, Nario KUNO4,5,12, Tomofumi UMEMOTO2,6, Tetsuhiro MINAMIDANI2,6,7, Mitsuhiro MATSUO2, Ryosuke KIRIDOSHI3, Kazuki TOKUDA3,7, Misaki HANAOKA1, Yuya TSUDA8, Mika KURIKI4, Akio OHAMA1, Hidetoshi SANO1,7,9, Tetsuo HASEGAWA7, Yoshiaki SOFUE10, Asao HABE11, Toshikazu ONISHI3 and Yasuo FUKUI1,9 1Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan 2Nobeyama Radio Observatory, National Astronomical Observatory of Japan (NAOJ), National Institutes of Natural Sciences (NINS), 462-2, Nobeyama, Minamimaki, Minamisaku, Nagano 384-1305, Japan 3Department of Physical Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan 4Department of Physics, Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba, Ibaraki 305-8577, Japan 5Tomonaga Center for the History of the Universe, University of Tsukuba, Ten-nodai 1-1-1, Tsukuba, Ibaraki 305-8571, Japan 6Department of Astronomical Science, School of Physical Science, SOKENDAI (The Graduate University for Advanced Studies), 2-21-1, Osawa, Mitaka, Tokyo 181-8588, Japan 7National Astronomical Observatory of Japan (NAOJ),
    [Show full text]
  • Structure and Kinematics of the Clouds Surrounding the Galactic Mini-Starburst W43 MM1 T
    A&A 595, A66 (2016) Astronomy DOI: 10.1051/0004-6361/201628653 & c ESO 2016 Astrophysics Structure and kinematics of the clouds surrounding the Galactic mini-starburst W43 MM1 T. Jacq1, J. Braine1, F. Herpin1, F. van der Tak2; 4, and F. Wyrowski3 1 Laboratoire d’Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France e-mail: [email protected] 2 SRON Netherlands Institute for Space Research, PO Box 800, 9700AV Groningen, The Netherlands 3 Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany 4 Kapteyn Astronomical Institute, University of Groningen, 9712 CP Groningen, The Netherlands Received 6 April 2016 / Accepted 28 July 2016 ABSTRACT Massive stars have a major influence on their environment, yet their formation is difficult to study as they form quickly in highly obscured regions and are rare, hence more distant than lower mass stars. Westerhout 43 (W43) is a highly luminous galactic massive star-forming region at a distance of 5.5 kpc and the MM1 part hosts a particularly massive dense core (1000 M within 0.05 pc). We present new Herschel HIFI maps of the W43 MM1 region covering the main low-energy water lines at 557, 987, and 1113 GHz; 18 13 18 their H2 O counterparts; and other lines such as CO (10–9) and C O (9–8), which trace warm gas. These water lines are, with the exception of line wings, observed in absorption. Herschel SPIRE and JCMT 450 µm data have been used to make a model of the continuum emission at the HIFI wavelengths.
    [Show full text]
  • RADIO EMISSION from 16 POSSIBLE SUPERNOVA REMNANTS by D. K. MILNE* and E. R. HILL* 1. INTRODUCTION There Are Some 40 Radio Sourc
    RADIO EMISSION FROM 16 POSSIBLE SUPERNOVA REMNANTS By D. K. MILNE* and E. R. HILL* [Manuscript received August 29, 1968] Summary Sixteen radio sources, thought to be supernova remnants, have been observed at several frequencies between 408 and 2700 MHz. These data, together with previously published observations, have been used to derive spectra for these sources. The validity of the supernova remnant classification of certain of these sources is questioned. 1. INTRODUCTION There are some 40 radio sources classified in the literature as remnants of galactic supernovae. T:Q.e identification of these objects has generally followed the rules: (1) The radio spectrum is nonthermal. (2) The angular size is large enough to exclude identification as an external galaxy. (3) The object should be a population I member (i.e. within 250 pc of the galactic plane). (4) If the source is visible optically, then it should not be an HII region, and preferably should show some of the characteristic filamentary structure usually associated with supernova remnants. (5) A radio brightness distribution indicating a shell structure. To date the radio data available for these objects have been scant, particularly for certain of the southern sources. Within the range of the Parkes 210 ft radio telescope (declination +27° to -90°) there are 24 radio sources classified as galactic supernova remnants. Some of these have been examined using the Parkes facilities (e.g. Gardner and Milne 1965; Hill 1967 ; Whiteoak and Gardner 1967; Milne 1968a) whilst for the other remnants often the only data available are from the low-resolution galactic surveys (e.g.
    [Show full text]
  • Structure and Kinematics of the Clouds Surrounding the Galactic Mini-Starburst W43 MM1 Jacq, T.; Braine, J.; Herpin, F.; Van Der Tak, F.; Wyrowski, F
    University of Groningen Structure and kinematics of the clouds surrounding the Galactic mini-starburst W43 MM1 Jacq, T.; Braine, J.; Herpin, F.; van der Tak, F.; Wyrowski, F. Published in: Astronomy and astrophysics DOI: 10.1051/0004-6361/201628653 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: 2016 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Jacq, T., Braine, J., Herpin, F., van der Tak, F., & Wyrowski, F. (2016). Structure and kinematics of the clouds surrounding the Galactic mini-starburst W43 MM1. Astronomy and astrophysics, 595(November 2016 ), [A66]. https://doi.org/10.1051/0004-6361/201628653 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.
    [Show full text]
  • The Bones of the Milky Way.Pdf (6.732Mb)
    The Bones of the Milky Way The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Goodman, Alyssa A., João Alves, Christopher N. Beaumont, Robert A. Benjamin, Michelle A. Borkin, Andreas Burkert, Thomas M. Dame et al. "The bones of the Milky Way." The Astrophysical Journal 797, no. 1 (2014): 53. Published Version doi:10.1088/0004-637X/797/1/53 Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:12655583 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Open Access Policy Articles, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#OAP The Bones of the Milky Way Alyssa A. Goodman Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 Jo~aoAlves University of Vienna, 1180 Vienna, Austria Christopher N. Beaumont Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 Robert A. Benjamin University of Wisconsin-Whitewater, Whitewater, WI 53190 Michelle A. Borkin Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 Andreas Burkert University of Munich, Munich, Germany Thomas M. Dame Smithsonian Astrophysical Observatory, Cambridge, MA 02138 James Jackson Boston University, Boston, MA 02215 Jens Kauffmann California Institute of Technology, Pasadena, CA 91125 Thomas Robitaille Max Planck Institute for Astronomy, Heidelberg, Germany Received ; accepted To appear in The Astrophysical Journal (ApJ) –2– ABSTRACT The very long and thin infared dark cloud “Nessie” is even longer than had been previously claimed, and an analysis of its Galactic location suggests that it lies directly in the Milky Way’s mid-plane, tracing out a highly elongated bone- like feature within the prominent Scutum-Centaurus spiral arm.
    [Show full text]
  • The O-And B-Type Stellar Population in W3: Beyond the High-Density Layer
    Accepted to ApJ: 30 August 2015 A Preprint typeset using LTEX style emulateapj v. 08/22/09 THE O- AND B-TYPE STELLAR POPULATION IN W3: BEYOND THE HIGH-DENSITY LAYER Megan M. Kiminki1, Jinyoung Serena Kim1, Micaela B. Bagley1,2, William H. Sherry3,4, and George H. Rieke1 Accepted to ApJ: 30 August 2015 ABSTRACT We present the first results from our survey of the star-forming complex W3, combining V RI pho- tometry with multiobject spectroscopy to identify and characterize the high-mass stellar population across the region. With 79 new spectral classifications, we bring the total number of spectroscopically- confirmed O- and B-type stars in W3 to 105. We find that the high-mass slope of the mass function in W3 is consistent with a Salpeter IMF, and that the extinction toward the region is best characterized by an RV of approximately 3.6. B-type stars are found to be more widely dispersed across the W3 giant molecular cloud (GMC) than previously realized: they are not confined to the high-density layer (HDL) created by the expansion of the neighboring W4 H II region into the GMC. This broader B-type population suggests that star formation in W3 began spontaneously up to 8–10 Myr ago, although at a lower level than the more recent star formation episodes in the HDL. In addition, we describe a method of optimizing sky subtraction for fiber spectra in regions of strong and spatially-variable nebular emission. Subject headings: dust, extinction — open clusters and associations: individual (Westerhout 3) — stars: early-type — stars: formation — stars: luminosity function, mass function 1.
    [Show full text]
  • Star Formation and Molecular Clouds Towards the Galactic Anti-Center
    Handbook of Star Forming Regions Vol. I Astronomical Society of the Pacific, c 2008 Bo Reipurth, ed. Star Formation and Molecular Clouds towards the Galactic Anti-Center Bo Reipurth Institute for Astronomy, University of Hawaii 640 N. Aohoku Place, Hilo, HI 96720, USA Chi-Hung Yan Institute of Astronomy and Astrophysics, Academia Sinica P.O. Box 23-141, Taipei 10617, Taiwan National Taiwan Normal University 88 Sec. 4, Tingzhou Road, Taipei, 11766, Taiwan Abstract. The Galactic Anticenter region hosts a a number of massive molecular cloud complexes, some of which are currently actively forming stars. Two major OB associations, Gem OB1 and Aur OB1, are found in this direction, each with numerous massive stars and a supernova remnant. The dominant region of star formation is cen- tered around the Sh 2-235 complex and the nearby regions AFGL 5142, 5144, and 5157 towards Aur OB1. Studies of these regions have long been affected by relatively poor distance determinations, although there is general consensus that most regions are lo- cated at distances between 1.5 and 2 kpc. A number of well-known, relatively isolated Herbig Ae/Be stars are found in this general direction, including RR Tau, HD 250550, and LkHα 208. 1. Overview The region towards the Galactic Anticenter is rich in molecular clouds and star forma- tion activity, although most is located at a considerable distance. In this chapter, we summarize key features of the principal regions of star formation out to approximately 2 kpc. A number of very interesting regions exist at larger distances, but those are be- yond the scope of this review.
    [Show full text]
  • Submitted to the Combined Faculties for the Natural Sciences and For
    Dissertation submitted to the Combined Faculties for the Natural Sciences and for Mathematics of the Ruperto-Carola University of Heidelberg, Germany for the degree of Doctor of Natural Sciences presented by Diplom-Physikerin Jessica Agarwal Born in Kiel, Germany Oral examination: 26 July 2007 The Emission of Large Dust Particles from Comet 67P/Churyumov-Gerasimenko Constrained by Observation and Modelling of its Dust Trail Referees: Prof. Dr. Eberhard Grun¨ Simon F. Green, PhD Zusammenfassung. Gegenstand der Arbeit ist die Untersuchung von Staubteilchen des Kometen 67P/Chur- yumov-Gerasimenko, die großer¨ als 60µm sind. Zu diesem Zweck werden astronomische Bilder des Staub-Trails dieses Kometen ausgewertet. Solche Teilchen stellen den großten¨ Teil der Staubmasse dar, die von Kometen in den interplanetaren Raum eingetragen wer- den. Im Gegensatz zu kleineren Teilchen verbleiben sie auf Trajektorien, die der des Ko- meten sehr ahnlich¨ sind. Dem Beobachter erscheinen sie als eine schmale Struktur entlang des projizierten Kometenorbits, die als Staub-Trail bezeichnet wird. Die erste im Rahmen dieser Arbeit untersuchte Beobachtung wurde im April 2004 in sichtbarem Licht mit dem Wide Field Imager am ESO/MPG-2.2m-Teleskop auf La Silla (Chile) durchgefuhrt.¨ Der Abstand des Kometen von der Sonne betrug zu diesem Zeitpunkt 4.7 A.E. Zwei weitere Beobachtungen wurden im August 2005 und im April 2006 im mittleren Infrarot (24 µm) ausgefuhrt¨ mit der MIPS-Kamera auf dem Spitzer-Weltraumteleskop. In beiden Fallen¨ war der Komet 5.7 A.E. von der Sonne entfernt. In der dazwischenliegenden Zeit, im No- vember 2005, hatte er das Aphel passiert. Zur Interpretation der Daten werden simulierte Trailbilder erzeugt.
    [Show full text]