DOCSLIB.ORG

National Radio Astronomy Observatory Quarterly

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
National Radio Astronomy Observatory Quarterly Qs V'O6?-AzIJJ NATIONAL RADIO ASTRONOMY OBSERVATORY QUARTERLY REPORT January 1 - March 31, 1990 APr TABLE OF CONTENTS A. TELESCOPE USAGE .1.. .. ... ............................... 1 B. 140-FOOT TELESCOPE1 ... ........ ............................. 1 C. 12-METER TELESCOPE6 ......... ............................. 6 D. VERY LARGE ARRAY9 .. ........ .............................. 9 E. SCIENTIFIC HIGHLIGHTS .. ........ ............................ 20 F. PUBLICATIONS ... ........ ................................ 21 G. CENTRAL DEVELOPMENT LABORATORY . ....... ....................... 21 H. GREEN BANK ELECTRONICS . ........ ........................... 23 I. 12-METER ELECTRONICS . ........ .............................. 25 J. VLA ELECTRONICS .. ........ ............................... 25 K. AIPS .. ........ .................................... 28 L. VLA COMPUTER .. ....... ................................ 28 M. VERY LONG BASELINE ARRAY . ........ .......................... 29 N. PERSONNEL ... .......... .................................. 32 APPENDIX A: LIST OF NRAO PREPRINTS A. TELESCOPE USAGE The NRAO telescopes have been scheduled for research and maintenance in the following manner during the first quarter of 1990. 140-ft 12-meter VIA Scheduled observing (hours) 1935.00 1772.25 1624.6 Scheduled maintenance and equipment changes 193.5 116.25 264.6 Scheduled tests and calibrations 127.25 261.50 261.6 Time lost 103.75 366.25 78.0 Actual observing 1831.25 1496.00 1546.7 B. 140-FOOT TELESCOPE The following line programs were conducted during the quarter. No. Observer(s) Program B-492 Bell, M. (Herzberg) Spectral survey of IRC+10216 over the Feldman, P (Herzberg) range 22.0-24.5 GHz. Matthews, H. (Herzberg) B-524 Bell, M. (Herzberg) . Studies at 17.5-24.5 GHz of heavy Avery, L. (Herzberg) molecule chemistry in shocked and Feldman, P. (Herzberg) unshocked gas in Orion. Matthews, H. (Herzberg) B-492 Bell, M. (Herzberg) Spectral survey of IRC+10216 over the Feldman, P. (Herzberg) range 22.0-24.5 GHz. Matthews, H. (Herzberg) B-525 Bell, M. (Herzberg) Observations at 17.25 GHz of Seaquist, E. (Toronto) redshifted C3H 2 in absorption against NGC 1275. B-533 Bell, M. (Herzberg) Observations at 22.235 GHz to examine Seaquist, E. (Toronto) the dust lane and nuclear region of Centaurus A. C-257 Clark, F. (Air Force Geophys. Lab) Observations of 2 cm H2 CO infrared Mann, P. (Kentucky) objects. LaHaise, W. (Kentucky) No. Observer(s) Program K-323 Koempe, C. (Herzberg) Search at discrete frequencies over Mann, P. (Kentucky) the range 18.5-23.6 GHz for NH3 LaHaise, W. (Kentucky) emission in the S247/S252 gas complex. L-238 Lee, Y. (Leiden) Study H2 CO at 2 cm to compare with CO Greenberg, J. (Leiden) data to establish dust correlation in Minn, Y. (Kyung Hee, Korea) dense dark clouds. L-284 Madden, S. (Massachusetts) Time variability study of ammonia Brown, R. (Monash Univ.) masers at 1.5 cm. Godfrey, P. (Monash Univ.) Henkel, C. (MPIR, Bonn) Irvine, W. (Massachusetts) Wilson, T. (MPIR, Bonn) Maddalena, R. M-309 Mutel, R. (Iowa) Survey of the galactic plane for Allen, J. (Iowa) 18 cm OH masers and confirmation of three newly discovered OH masers that are coincident with IRAS sources. T-272 Turner, B. Studies at 2 cm of H2 CO in Cirrus Rickard, L. J (NRL) Clouds. Lanping, X. V-72 Vanden Bout, P. Search in the range 21-23 GHz for CO Brown, R. emission in high-Z QSO's. W-269 Wilson, T. (MPIR) Search at 18.2 GHz for the 2-1 line Batrla, W. of HC3N toward Cas A. W-271 Williams, D. (Berkeley) Search for the 17.5 GHz transition of + Shuter, W. (British Columbia) H2 in Jupiter and the interstellar medium. W-280 Wootten, H. A. H20 monitoring in star-forming cores in Rho Oph. The following pulsar programs were conducted during this quarter. No. Observer(s) Program B-484 Backer, D. (Berkeley) Timing observations at 750-800 and at Foster, R. (Berkeley) 1330 MHz of PSR 1821-24 and other millisecond pulsars. No. Observer(s) Program T-265 Taylor, J. (Princeton) Pulsar timing observations over the Stinebring, D. (Princeton) range 390-450 and 1355 MHz. Dewey, R. (JPL) Nice, D. (Princeton) Thorsett, S. (Princeton) Arzoumanian, Z. (Princeton) T-280 Taylor, J. (Princeton) Studies at 18 cm of the eclipsing Fruchter, A. (DTM) millisecond pulsar in Terzan 5. Stinebring, D. (Princeton) Nice, D. (Princeton) Thorsett, S. (Princeton) The following very long baseline programs were conducted. The stations used for the observations are coded as follows: A Arecibo 1000 ft Me Merlin B Effelsburg, MPIR 100 m N NRL Maryland Point 85 ft E Hartebeesthoek, South Africa No Noto, Sicily F Fort Davis 85 ft Pt Pietown 25 m G Green Bank 140 ft R Crimea, USSR 30 m H Hat Creek 26 m Sa Shanghai 25 m I Iowa 60 ft So Onsala 25 m Jb Jodrell Bank 250 ft T Torun 15 m Km Haystack 120 ft Wn Westerbork n = 1-14x26m Kp Kitt Peak 25 m X Itapetinga 20 m Lb Bologna 25 m Yn Socorro n=l-27x25 m No. Observer(s) Program A-31V Abraham, Z. (Itapetinga) Time evolution studies of 3C 273 and Zensus, A. 3C 279 at 2.8 and 6 cm, with Carrara, E. (Itapetinga) telescopes B, Lm, No, Km, G, F, O, H. Unwin, S. (Caltech) Pt, A, Mb, and E. Cohen, M. (Caltech) Nocholson, G. (Hartebeesthoek) AH-48V Lonsdale, C. (Haystack) Search at 18 cm for fringes from Weecdmnan, D. (Pennsylvania) component A of the interacting galaxy Lonsdale, C. J. (Caltech) system NGC 3690, with telescopes G, Smith, H. (UCSD) 0, and Pt. B-82V Bartel, N. (CFA) Studies at 6 cm of the expansion and Rogers, A. (MIT) morphology of SN1979C, with Shapiro, I. (MIT) telescopes B, Wn, G, O, Y2 7 , and A. No. Observer(s) Program B-100V Biretta, J. Observations at 18 cm of the M87 Cawthorne, T. (Brandeis) nuclear jet, with telescopes B, So, Reid, M. (CFA) Lm, Wn, Jb, K, G, F, O, YY2 7 , A, and Gabuzda, D. (JPL) Pt. B-101V Benz, A. (ETH, Zurich) Studies at 18 cm of M-dwarfs, with Isliker, H. (ETH, Zurich) telescopes B, J, G, O. Y2 7 , and A. Alef, W. (MPIR, Bonn) de Vicente, P. (MPIR, Bonn) B-102V Bartel, N. (CFA) Studies at 18 cm to determine to Rogers, A. (MIT) what degree SN1979C is circularly Shapiro, I. (MIT) symmetric, with telescopes B, Wn, G, 0, Y2 7 , and A. C-56V Cordes, J. (Cornell) Astrometry at 18 cm of the binary Gwinn, C. (UCSB) pulsar 1913+16, with telescopes B, G, 0, Y27, and A. G-63V Gwinn, C. (CFA) Observations at 18 cm of OH maser Mutel, R. (Iowa) scattering disks in W49N, with Cordes, J. (Cornell) telescopes B, G, F, O, Y2 7 , A, Pt, Kp, Moran, J. (CFA) and A. Clegg, A. (CFA) H-48V Hough, D. (JPL) Measurements of superluminal motion Readhead, A. (Caltech) at 2.8 cm in weak nuclei of double- lobed quasars 3C 208, 3C 249.1, and 3C 247, with telescopes B, Km, G, and Pt. H-55V Hummel, K. (MPIR, Bonn) Studies at 6 cm of the "bridge" in Krichbaum, T. (MPIR, Bonn) the S5 quasar 0153+744, with Quirrenbach, A. (MPIR, Bonn) telescopes B, Wn, So, Lm, Jb, R, No, Schalinski, C. (MPIR, Bonn) Kin, G, F, 0, H, N, Pt, Kp, and La. Witzel, A. (MPIR, Bonn) Rioja, M. (MPIR, Bonn) Johnston, K. (NRL) L-57V Lonsdale, C. (Haystack) Observations at 18 cm of the hotspot Phillips, R. (Haystack) in 3C 263.1, with telescopes B, Jb, Barthel, P. (Groningen) G, and Y2 7 - Muxlow, T. (Manchester) 5 No. Observer(s) Program M-110V Mutel, R. (Iowa) Studies at 18 cm of interstellar Spangler, S. (Iowa) scattering effects of sources Molnar, L. (Iowa) exhibiting these properties, with Cordes, J. (Cornell) telescopes B, Lm, Wn, Km, G, F, O, Gwinn, C. (UCSB) Y2 7 , Pt, and A. Fey, A. (Iowa) M-111V Mutel, R. (Iowa) Monitor the core of BI Lac at 2.8 cm, Jie, D. (Iowa) with telescopes B, Lm, No, Km, G, F, Phillips, R. (Haystack) O, H, Pt, and Sa. M-112V Mutel, R. (Iowa) Multifrequency maps at 6 and 18 cm of Baum, S. (NFRA) the three compact doubles at 6 and O'Dea, C. (NFRA) 18 cm, with telescopes B, Lm, So, Wn, Jb, No, Km, G, O, Y2 7 , Pt, and Kp. P-92V Pauliny-Toth, I. (MPIR, Bonn) Monitor at 2.8 cm quasar 2134+004, Alberdi, A. (IAA, Audalucia) with telescopes B, Lm, R, Kin, G, F, Zensus, A. O, H, Pt, and Mb. Cohen, M. (Caltech) P-01V Phillips, R. (Haystack) Investigation at 6 and 18 cm of the Feigelson, E. (Penn State) compact nonthermal emission around Lonsdale, C. (Haystack) naked T Tauri stars, with telescopes B, Jb, G, O, Y2 7 , and A. R-49V Roberts, D. (Brandeis) Survey at 6 cm of the linear Brown, L. (Brandeis) structure of the Pearson-Readhead Cawthorne, T. (Brandeis) Sample, with telescopes B, Lm, So, Wardle, J. (Brandeis) Wn, K, G, F, O, and Pt. Gabuzda, D. (JPL) R-50V Roberts, D. (Brandeis) Measurements at 6 cm of the evolution Brown, L. (Brandeis) of the linear polarization structures Cawthorne, T. (Brandeis) of superluminal sources, with Wardle, J. (Brandeis) telescopes B, Lm, So, Wn, K, G, F, O, Gabuzda, D. (JPL) and Pt. R-51V Readhead, A. (Caltech) Large snapshot survey at 6 cm of Wilkinson, P. (Manchester) active galactic nuclei, with Xu, W. (Caltech) telescopes B, Lm, So, Wn, Jb, No, K, Pearson, T. (Caltech) G, F, 0, H. Pt, Kp, and La. Lawrence, C. (Caltech) Herbig, T. (Caltech) 6 No. Observer(s) Program V-3V Vermeulon, R. (Caltech) Observations at 18 cm of the radio Schilizzi, R. (NFRA) spectrum of the jets of SS433, with Spencer, R. (Manchester) telescopes Kin, G, F, 0, Y27, A, Din, Romney, J. and Pt. Preston, R. (JPL) Feges, I.
Load more

Recommended publications
  • A Hot Subdwarf-White Dwarf Super-Chandrasekhar Candidate
    A hot subdwarf–white dwarf super-Chandrasekhar candidate supernova Ia progenitor Ingrid Pelisoli1,2*, P. Neunteufel3, S. Geier1, T. Kupfer4,5, U. Heber6, A. Irrgang6, D. Schneider6, A. Bastian1, J. van Roestel7, V. Schaffenroth1, and B. N. Barlow8 1Institut fur¨ Physik und Astronomie, Universitat¨ Potsdam, Haus 28, Karl-Liebknecht-Str. 24/25, D-14476 Potsdam-Golm, Germany 2Department of Physics, University of Warwick, Coventry, CV4 7AL, UK 3Max Planck Institut fur¨ Astrophysik, Karl-Schwarzschild-Straße 1, 85748 Garching bei Munchen¨ 4Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106, USA 5Texas Tech University, Department of Physics & Astronomy, Box 41051, 79409, Lubbock, TX, USA 6Dr. Karl Remeis-Observatory & ECAP, Astronomical Institute, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Sternwartstr. 7, 96049 Bamberg, Germany 7Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA 8Department of Physics and Astronomy, High Point University, High Point, NC 27268, USA *[email protected] ABSTRACT Supernova Ia are bright explosive events that can be used to estimate cosmological distances, allowing us to study the expansion of the Universe. They are understood to result from a thermonuclear detonation in a white dwarf that formed from the exhausted core of a star more massive than the Sun. However, the possible progenitor channels leading to an explosion are a long-standing debate, limiting the precision and accuracy of supernova Ia as distance indicators. Here we present HD 265435, a binary system with an orbital period of less than a hundred minutes, consisting of a white dwarf and a hot subdwarf — a stripped core-helium burning star.
    [Show full text]
  • Správa O Činnosti Organizácie SAV Za Rok 2017
    Astronomický ústav SAV Správa o činnosti organizácie SAV za rok 2017 Tatranská Lomnica január 2018 Obsah osnovy Správy o činnosti organizácie SAV za rok 2017 1. Základné údaje o organizácii 2. Vedecká činnosť 3. Doktorandské štúdium, iná pedagogická činnosť a budovanie ľudských zdrojov pre vedu a techniku 4. Medzinárodná vedecká spolupráca 5. Vedná politika 6. Spolupráca s VŠ a inými subjektmi v oblasti vedy a techniky 7. Spolupráca s aplikačnou a hospodárskou sférou 8. Aktivity pre Národnú radu SR, vládu SR, ústredné orgány štátnej správy SR a iné organizácie 9. Vedecko-organizačné a popularizačné aktivity 10. Činnosť knižnično-informačného pracoviska 11. Aktivity v orgánoch SAV 12. Hospodárenie organizácie 13. Nadácie a fondy pri organizácii SAV 14. Iné významné činnosti organizácie SAV 15. Vyznamenania, ocenenia a ceny udelené organizácii a pracovníkom organizácie SAV 16. Poskytovanie informácií v súlade so zákonom o slobodnom prístupe k informáciám 17. Problémy a podnety pre činnosť SAV PRÍLOHY A Zoznam zamestnancov a doktorandov organizácie k 31.12.2017 B Projekty riešené v organizácii C Publikačná činnosť organizácie D Údaje o pedagogickej činnosti organizácie E Medzinárodná mobilita organizácie F Vedecko-popularizačná činnosť pracovníkov organizácie SAV Správa o činnosti organizácie SAV 1. Základné údaje o organizácii 1.1. Kontaktné údaje Názov: Astronomický ústav SAV Riaditeľ: Mgr. Martin Vaňko, PhD. Zástupca riaditeľa: Mgr. Peter Gömöry, PhD. Vedecký tajomník: Mgr. Marián Jakubík, PhD. Predseda vedeckej rady: RNDr. Luboš Neslušan, CSc. Člen snemu SAV: Mgr. Marián Jakubík, PhD. Adresa: Astronomický ústav SAV, 059 60 Tatranská Lomnica http://www.ta3.sk Tel.: 052/7879111 Fax: 052/4467656 E-mail: [email protected] Názvy a adresy detašovaných pracovísk: Astronomický ústav - Oddelenie medziplanetárnej hmoty Dúbravská cesta 9, 845 04 Bratislava Vedúci detašovaných pracovísk: Astronomický ústav - Oddelenie medziplanetárnej hmoty prof.
    [Show full text]
  • RESEARCH PROGRAMS 140-Foot Telescope
    VS/G LI NATIONAL RADIO ASTRONOMY OBSERVATORY Charlottesville, Virginia r Quarterly Report October 1, 1981 - December 31, 1981 RESEARCH PROGRAMS 140-foot Telescope Hours Scheduled observing 1955.75 Scheduled maintenance and equipment changes 179.25 Scheduled tests and calibration 1.00 Time lost due to: equipment failure 34.75 power 9.50 weather 133.25 interference 0.00 The following line programs were conducted during this quarter. No. Observer (s) Program T-156 I. Kazes (Meudon, France) Observations to study giant molecular B. Turner clouds at the main 18 cm OH line frequencies. T-145 B. Turner Search within the 13-16 GHz range for new molecular species. S-233 L. Buxton (Illinois) Observations at 20.9 and 24.4 GHz to E. Campbell (Illinois) search for the HCN dimer (HCN) 2 . W. Flygare (Illinois) P. Jewell (Illinois) M. Schenewerk (Illinois) L. Snyder (Illinois) B-381 R. Brown Observations at 5-cm to confirm and extend the detection of recombination line emission from 3C 245 and a search for this type of emission from other QSOs. S-246 M. Bell (NRC, Canada) Search at 5 cm for recombination lines E. Seaquist (Toronto) in compact extragalactic sources. No. Observer(s) Program M-176 L. Avery (NRC, Canada) Observations at 18.2 GHz of the J=241 N. Broten (NRC, Canada) transition of HC3N, generally toward J. MacLeod (NRC, Canada) dark clouds. H. Matthews (NRC, Canada T. Oka (Chicago) The following continuum programs were conducted during this quarter. No. Observer (s) Program C-194 M. Condon (unaffiliated) Survey at 14.5 cm of extragalactic J.
    [Show full text]
  • Appendix: Spectroscopy of Variable Stars
    Appendix: Spectroscopy of Variable Stars As amateur astronomers gain ever-increasing access to professional tools, the science of spectroscopy of variable stars is now within reach of the experienced variable star observer. In this section we shall examine the basic tools used to perform spectroscopy and how to use the data collected in ways that augment our understanding of variable stars. Naturally, this section cannot cover every aspect of this vast subject, and we will concentrate just on the basics of this field so that the observer can come to grips with it. It will be noticed by experienced observers that variable stars often alter their spectral characteristics as they vary in light output. Cepheid variable stars can change from G types to F types during their periods of oscillation, and young variables can change from A to B types or vice versa. Spec­ troscopy enables observers to monitor these changes if their instrumentation is sensitive enough. However, this is not an easy field of study. It requires patience and dedication and access to resources that most amateurs do not possess. Nevertheless, it is an emerging field, and should the reader wish to get involved with this type of observation know that there are some excellent guides to variable star spectroscopy via the BAA and the AAVSO. Some of the workshops run by Robin Leadbeater of the BAA Variable Star section and others such as Christian Buil are a very good introduction to the field. © Springer Nature Switzerland AG 2018 M. Griffiths, Observer’s Guide to Variable Stars, The Patrick Moore 291 Practical Astronomy Series, https://doi.org/10.1007/978-3-030-00904-5 292 Appendix: Spectroscopy of Variable Stars Spectra, Spectroscopes and Image Acquisition What are spectra, and how are they observed? The spectra we see from stars is the result of the complete output in visible light of the star (in simple terms).
    [Show full text]
  • Observational Cosmology - 30H Course 218.163.109.230 Et Al
    Observational cosmology - 30h course 218.163.109.230 et al. (2004–2014) PDF generated using the open source mwlib toolkit. See http://code.pediapress.com/ for more information. PDF generated at: Thu, 31 Oct 2013 03:42:03 UTC Contents Articles Observational cosmology 1 Observations: expansion, nucleosynthesis, CMB 5 Redshift 5 Hubble's law 19 Metric expansion of space 29 Big Bang nucleosynthesis 41 Cosmic microwave background 47 Hot big bang model 58 Friedmann equations 58 Friedmann–Lemaître–Robertson–Walker metric 62 Distance measures (cosmology) 68 Observations: up to 10 Gpc/h 71 Observable universe 71 Structure formation 82 Galaxy formation and evolution 88 Quasar 93 Active galactic nucleus 99 Galaxy filament 106 Phenomenological model: LambdaCDM + MOND 111 Lambda-CDM model 111 Inflation (cosmology) 116 Modified Newtonian dynamics 129 Towards a physical model 137 Shape of the universe 137 Inhomogeneous cosmology 143 Back-reaction 144 References Article Sources and Contributors 145 Image Sources, Licenses and Contributors 148 Article Licenses License 150 Observational cosmology 1 Observational cosmology Observational cosmology is the study of the structure, the evolution and the origin of the universe through observation, using instruments such as telescopes and cosmic ray detectors. Early observations The science of physical cosmology as it is practiced today had its subject material defined in the years following the Shapley-Curtis debate when it was determined that the universe had a larger scale than the Milky Way galaxy. This was precipitated by observations that established the size and the dynamics of the cosmos that could be explained by Einstein's General Theory of Relativity.
    [Show full text]
  • AG€Pegasi – Now a Classical Symbiotic Star in Outburst?
    MNRAS 462, 4435–4441 (2016) doi:10.1093/mnras/stw2012 Advance Access publication 2016 August 12 AG Pegasi – now a classical symbiotic star in outburst? T. V. Tomov,1‹ K. A. Stoyanov2 and R. K. Zamanov2 1Centre for Astronomy, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, PL-87-100 Torun, Poland 2Institute of Astronomy and National Astronomical Observatory, Bulgarian Academy of Sciences, Tsarigradsko Shose 72, 1784 Sofia, Bulgaria Accepted 2016 August 9. Received 2016 August 8; in original form 2016 March 18 Downloaded from https://academic.oup.com/mnras/article/462/4/4435/2590002 by EIFL - Bulgaria user on 02 June 2021 ABSTRACT Optical spectroscopy study of the recent AG Pegasi (AG Peg) outburst observed during the second half of 2015 is presented. Considerable variations of the intensity and the shape of the spectral features as well as the changes of the hot component parameters, caused by the outburst, are discussed and certain similarities between the outburst of AG Peg and the outburst of a classical symbiotic stars are shown. It seems that after the end of the symbiotic nova phase, AG Peg became a member of the classical symbiotic stars group. Key words: binaries: symbiotic – stars: individual: AG Pegasi. orbit for AG Peg. Recent observations show that the gradual bright- 1 INTRODUCTION ness decline ceased and the present brightness shows only orbitally AG Pegasi (AG Peg) is the oldest symbiotic nova which attracted related wave-like variations around the mean brightness (Skopal astronomers’ attention with the first spectral observations performed et al. 2012). by Fleming (1894).
    [Show full text]
  • On the Study of Atomic and Molecular Processes Affecting Astrophysical
    On the study of atomic and molecular processes affecting Astrophysical Plasma using high-resolution optical and UV spectroscopy by Ahmad Nemer A dissertation submitted to the Graduate Faculty of Auburn University in partial fulfillment of the requirements for the Degree of Doctor of Philosophy Auburn, Alabama August 3, 2019 Keywords: Recombination, evidence, dissociation Copyright 2019 by Ahmad Nemer Approved by Stuart Loch, Chair, Associate Professor of Physics Allen Landers, Professor of Physics Mike Fogle, Associate Professor of Physics Mitch Pindzola, Professor of Physics Laurent Guillaume, Associate Professor of Physics Evangelos Miliordos, Assistant Professor of Chemistry Abstract Rydberg Enhanced Recombination (RER), a recombination process related to dielec- tronic recombination in which electrons are captured into energy states below the ionization threshold, has been theoretically predicted to occur in low temperature plasmas. First evi- dence of RER is shown to occur in astrophysical environments, using high resolution optical spectra of planetary nebulae and a UV spectrum of symbiotic stars. RER can significantly impact diagnosed ionic and elemental abundances of important astrophysical species, with implications for cosmological models. The project underlines the importance of including this process in models of photoionized plasmas. ii Acknowledgments This work was funded by a NASA grant to Auburn University (). We thank Dr. Francis Robicheaux for his original work on this subject. We also thank Dr. Daniel Savin and Dr. Randall Smith for the very useful feedback they gave on this work. The work of students Pierce Jackson, Sammy Rizzutto, and Matt Gill are also gratefully acknowledged. iii Table of Contents Abstract . ii Acknowledgments . iii List of Figures .
    [Show full text]
  • Summer Solstice 1988 No
    Summer Solstice 1988 No. 59 ISSN 0715-4747 • ... ...\., ......... ..... ~ .., ~ Lu 41 Q. o (/) (/) II( U • • .' ' . .. 'I ". ,,- vex ..I C.A.S . Board of Directors President G. Michaud, U. de Montreal First Vice-President S. van den Bergh, D.A.O. Second Vice-President L. Higgs, D. R.A.O . Secretary C. Aikman, D.A.O. Treasurer J. Climenhaga, U. of Victoria Directors P. Martin, C.I . T.A. S. Pineault, U. Laval R. Roger, D.R.A.O. C.A.S. Committee Chairmen Awards P. Martin, C.I.T.A. Computing Facilities C. Pritchet, U. of Victoria Education R. Bochonko, U. of Manitoba Heritage P. Millman, H. I . A. Optical and Infrared Astronomy G. Harris, U. of Waterloo Radio Astronomy P. Dewdney, D.R .A.O. (acting) Small Grants C. Purton, D.R .A. O. Space Astronomy J. Hesser, D.A.O. Editor: Colin Scarfe Address: Department of Physics and Astronomy University of Victoria Victoria, B.C. V8W2Y2 Telephone: (604)721-7740 FAX: (604)721-7715 BITNET: SCARFE@UVPHYS 2 Cassiopeia EDITORIAL Since the last issue of Cassiopeia, there has been much di s~ ussion and act.ivity on initiatives toward possible new Canadian optical telescopes, and indeed several pages of this issue are concerned wholly or partly with that topic. We have debated the sc. ientific merits of a moderately large high-resolution telescope, already discussed in earlier issues by No. 59 Summer Solstice 1988 Rene Racine, and of obtaining a share of one (or more) of the several very large tcleswpcs now being proposed, designed or constructed. We have learned a little nbout radical new designs involving liquids, either as optical elements or as support mechanisms, which may perhaps lead to much reduced costs, but whose usefulness and versatility is so far unknown.
    [Show full text]
  • Lectures on Astronomy, Astrophysics, and Cosmology
    Lectures on Astronomy, Astrophysics, and Cosmology Luis A. Anchordoqui Department of Physics and Astronomy, Lehman College, City University of New York, NY 10468, USA Department of Physics, Graduate Center, City University of New York, 365 Fifth Avenue, NY 10016, USA Department of Astrophysics, American Museum of Natural History, Central Park West 79 St., NY 10024, USA (Dated: Spring 2016) I. STARS AND GALAXIES minute = 1:8 107 km, and one light year × 1 ly = 9:46 1015 m 1013 km: (1) A look at the night sky provides a strong impression of × ≈ a changeless universe. We know that clouds drift across For specifying distances to the Sun and the Moon, we the Moon, the sky rotates around the polar star, and on usually use meters or kilometers, but we could specify longer times, the Moon itself grows and shrinks and the them in terms of light. The Earth-Moon distance is Moon and planets move against the background of stars. 384,000 km, which is 1.28 ls. The Earth-Sun distance Of course we know that these are merely local phenomena is 150; 000; 000 km; this is equal to 8.3 lm. Far out in the caused by motions within our solar system. Far beyond solar system, Pluto is about 6 109 km from the Sun, or 4 × the planets, the stars appear motionless. Herein we are 6 10− ly. The nearest star to us, Proxima Centauri, is going to see that this impression of changelessness is il- about× 4.2 ly away. Therefore, the nearest star is 10,000 lusory.
    [Show full text]
  • The Formation of the Double Gaussian Line Profiles Of
    Journal of the Korean Astronomical Society https://doi.org/10.5303/JKAS.2020.53.2.35 53: 35 ∼ 42, 2020 April pISSN: 1225-4614 · eISSN: 2288-890X Published under Creative Commons license CC BY-SA 4.0 http://jkas.kas.org THE FORMATION OF THE DOUBLE GAUSSIAN LINE PROFILES OF THE SYMBIOTIC STAR AG PEGASI Siek Hyung and Seong-Jae Lee Department of Earth Science Education (Astronomy), Chungbuk National University, Chungbuk 28644, Korea [email protected], [email protected] Received December 12, 2019; accepted February 8, 2020 Abstract: We analyze high dispersion emission lines of the symbiotic nova AG Pegasi, observed in 1998, 2001, and 2002. The Hα and Hβ lines show three components, two narrow and one underlying broad line components, but most other lines, such as H i, He i, and He ii lines, show two blue- and red-shifted components only. A recent study by Lee & Hyung(2018) suggested that the double Gaussian lines emitted from a bipolar conical shell are likely to form Raman scattering lines observed in 1998. In this study, we show that the bipolar cone with an opening angle of 74◦, which expands at a velocity of 70 km s−1 along the polar axis of the white dwarf, can accommodate the observed double line profiles in 1998, 2001, and 2002. We conclude that the emission zone of the bipolar conical shell, which formed along the bipolar axis of the white dwarf due to the collimation by the accretion disk, is responsible for the double Gaussian profiles. Key words: stars: binaries: symbiotic | stars: individual: AG Peg { ISM: dynamics and kinematics | ISM: lines and bands 1.I NTRODUCTION a GS transit cannot form the observed Gaussian line Symbiotic stars are identified as binary systems by their profiles.
    [Show full text]
  • Astrophysics
    Publications of the Astronomical Institute rais-mf—ii«o of the Czechoslovak Academy of Sciences Publication No. 70 EUROPEAN REGIONAL ASTRONOMY MEETING OF THE IA U Praha, Czechoslovakia August 24-29, 1987 ASTROPHYSICS Edited by PETR HARMANEC Proceedings, Vol. 1987 Publications of the Astronomical Institute of the Czechoslovak Academy of Sciences Publication No. 70 EUROPEAN REGIONAL ASTRONOMY MEETING OF THE I A U 10 Praha, Czechoslovakia August 24-29, 1987 ASTROPHYSICS Edited by PETR HARMANEC Proceedings, Vol. 5 1 987 CHIEF EDITOR OF THE PROCEEDINGS: LUBOS PEREK Astronomical Institute of the Czechoslovak Academy of Sciences 251 65 Ondrejov, Czechoslovakia TABLE OF CONTENTS Preface HI Invited discourse 3.-C. Pecker: Fran Tycho Brahe to Prague 1987: The Ever Changing Universe 3 lorlishdp on rapid variability of single, binary and Multiple stars A. Baglln: Time Scales and Physical Processes Involved (Review Paper) 13 Part 1 : Early-type stars P. Koubsfty: Evidence of Rapid Variability in Early-Type Stars (Review Paper) 25 NSV. Filtertdn, D.B. Gies, C.T. Bolton: The Incidence cf Absorption Line Profile Variability Among 33 the 0 Stars (Contributed Paper) R.K. Prinja, I.D. Howarth: Variability In the Stellar Wind of 68 Cygni - Not "Shells" or "Puffs", 39 but Streams (Contributed Paper) H. Hubert, B. Dagostlnoz, A.M. Hubert, M. Floquet: Short-Time Scale Variability In Some Be Stars 45 (Contributed Paper) G. talker, S. Yang, C. McDowall, G. Fahlman: Analysis of Nonradial Oscillations of Rapidly Rotating 49 Delta Scuti Stars (Contributed Paper) C. Sterken: The Variability of the Runaway Star S3 Arietis (Contributed Paper) S3 C. Blanco, A.
    [Show full text]
  • Meeting Abstracts
    228th AAS San Diego, CA – June, 2016 Meeting Abstracts Session Table of Contents 100 – Welcome Address by AAS President Photoionized Plasmas, Tim Kallman (NASA 301 – The Polarization of the Cosmic Meg Urry GSFC) Microwave Background: Current Status and 101 – Kavli Foundation Lecture: Observation 201 – Extrasolar Planets: Atmospheres Future Prospects of Gravitational Waves, Gabriela Gonzalez 202 – Evolution of Galaxies 302 – Bridging Laboratory & Astrophysics: (LIGO) 203 – Bridging Laboratory & Astrophysics: Atomic Physics in X-rays 102 – The NASA K2 Mission Molecules in the mm II 303 – The Limits of Scientific Cosmology: 103 – Galaxies Big and Small 204 – The Limits of Scientific Cosmology: Town Hall 104 – Bridging Laboratory & Astrophysics: Setting the Stage 304 – Star Formation in a Range of Dust & Ices in the mm and X-rays 205 – Small Telescope Research Environments 105 – College Astronomy Education: Communities of Practice: Research Areas 305 – Plenary Talk: From the First Stars and Research, Resources, and Getting Involved Suitable for Small Telescopes Galaxies to the Epoch of Reionization: 20 106 – Small Telescope Research 206 – Plenary Talk: APOGEE: The New View Years of Computational Progress, Michael Communities of Practice: Pro-Am of the Milky Way -- Large Scale Galactic Norman (UC San Diego) Communities of Practice Structure, Jo Bovy (University of Toronto) 308 – Star Formation, Associations, and 107 – Plenary Talk: From Space Archeology 208 – Classification and Properties of Young Stellar Objects in the Milky Way to Serving
    [Show full text]