January 2017 BRAS Newsletter
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Ann Merchant Boesgaard Publications Merchant, A. E., Bodenheimer, P., and Wallerstein, G
Ann Merchant Boesgaard Publications Merchant, A. E., Bodenheimer, P., and Wallerstein, G. (1965). “The Lithium Isotope Ratio in Two Hyades F Stars.” Ap. J., 142, 790. Merchant, A. E. (1966). “Beryllium in F- and G-Type Dwarfs.” Ap. J., 143, 336. Hodge, P. W., and Merchant, A. E. (1966). “Photometry of SO Galaxies II. The Peculiar Galaxy NGC 128.” Ap. J., 144, 875. Merchant, A. E. (1967). “The Abundance of Lithium in Early M-Type Stars.” Ap. J., 147, 587. Merchant, A. E. (1967). “Measured Equivalent Widths in Early M-Type Stars.” Lick Obs. Bull. No. 595 (Univ. of California Press). Boesgaard, A. M. (1968). “Isotopes of Magnesium in Stellar Atmosphere.” Ap. J., 154, 185. Boesgaard, A. M. (1968). “Observations of Beryllium in Stars.” Highlights of Astron- omy, ed. L. Perek (Dordrecht: D. Reidel), p. 237. Boesgaard, A. M. (1969). “Intensity Variation in Ca Emission in an MS Star.” Pub. A. S. P., 81, 283. Boesgaard, A. M. (1969). “Observational Clues to the Evolution of M Giant Stars.” Pub. A. S. P., 81, 365. Boesgaard, A. M. (1970). “The Lithium Isotope Ratio in δ Sagittae.” Ap. J., 159, 727. Boesgaard, A. M. (1970). “The Ratio of Titanium to Zirconium in Late-Type Stars.” Ap. J., 161, 163. Boesgaard, A. M. (1970). “On the Lithium Content in Late-Type Giants.” Ap. Letters, 5, 145. Boesgaard, A. M. (1970). “Lithium in Heavy-Metal Red Giants.” Ap. J., 161, 1003. Boesgaard, A. M. (1971). “The Lithium Content of Capella.” Ap. J., 167, 511. Boesgaard, A. M. (1973). “Iron Emission Lines in a Orionis.” In Stellar Chromospheres, eds. -
The Photosphere and Circumstellar Environment of the Be Star Achernar
New windows on massive stars: asteroseismology, interferometry, and spectropolarimetry Proceedings IAU Symposium No. 307, 2014 c International Astronomical Union 2015 G.Meynet,C.Georgy,J.H.Groh&Ph.Stee,eds. doi:10.1017/S1743921314006905 The photosphere and circumstellar environment of the Be star Achernar Daniel M. Faes1,2, Armando Domiciano de Souza2,AlexC.Carciofi1 and Philippe Bendjoya2 1 Instituto de Astronomia, Geof´ısica e Ciˆencias Atmosf´ericas, Universidade de S˜ao Paulo, Rua do Mat˜ao 1226, Cidade Universit´aria, 05508-900, S˜ao Paulo, SP, Brazil email: [email protected] 2 Lab. J.-L. Lagrange, UMR 7293 - Observatoire de la Cˆote d’Azur (OCA), Univ. de Nice-Sophia Antipolis (UNS), CNRS, Valrose, 06108 Nice, France Abstract. Achernar is a key target to investigate high stellar rotation and the Be phenonemon. It is also the hottest star for which detailed photospheric information is available. Here we report our results to determine the photospheric parameters of Achernar and evaluate how the emission of a Viscous Decretion Disk (VDD) around it would be observable. The analysis is based on interferometric data (PIONIER and AMBER at ESO-VLTI), complemented by spectroscopy and polarimetry for the circumstellar emission. For the first time fundamental parameters of a Be photosphere were determined. The presence of a residual disk at the quiescent phase and some characteristics of the new formed disk (2013 activity) are also discussed. This is rare opportunity to precisely determine the stellar brightness distribution and evaluate the evolution of a just formed Be disk. Keywords. stars: individual (Achernar), stars: fundamental parameters, techniques: interfero- metric, circumstellar matter, stars: emission-line, Be 1. -
Milan Dimitrijevic Avgust.Qxd
1. M. Platiša, M. Popović, M. Dimitrijević, N. Konjević: 1975, Z. Fur Natur- forsch. 30a, 212 [A 1].* 1. Griem, H. R.: 1975, Stark Broadening, Adv. Atom. Molec. Phys. 11, 331. 2. Platiša, M., Popović, M. V., Konjević, N.: 1975, Stark broadening of O II and O III lines, Astron. Astrophys. 45, 325. 3. Konjević, N., Wiese, W. L.: 1976, Experimental Stark widths and shifts for non-hydrogenic spectral lines of ionized atoms, J. Phys. Chem. Ref. Data 5, 259. 4. Hey, J. D.: 1977, On the Stark broadening of isolated lines of F (II) and Cl (III) by plasmas, JQSRT 18, 649. 5. Hey, J. D.: 1977, Estimates of Stark broadening of some Ar III and Ar IV lines, JQSRT 17, 729. 6. Hey, J. D.: Breger, P.: 1980, Stark broadening of isolated lines emitted by singly - ionized tin, JQSRT 23, 311. 7. Hey, J. D.: Breger, P.: 1981, Stark broadening of isolated ion lines by plas- mas: Application of theory, in Spectral Line Shapes I, ed. B. Wende, W. de Gruyter, 201. 8. Сыркин, М. И.: 1981, Расчеты электронного уширения спектральных линий в теории оптических свойств плазмы, Опт. Спектроск. 51, 778. 9. Wiese, W. L., Konjević, N.: 1982, Regularities and similarities in plasma broadened spectral line widths (Stark widths), JQSRT 28, 185. 10. Konjević, N., Pittman, T. P.: 1986, Stark broadening of spectral lines of ho- mologous, doubly ionized inert gases, JQSRT 35, 473. 11. Konjević, N., Pittman, T. P.: 1987, Stark broadening of spectral lines of ho- mologous, doubly - ionized inert gases, JQSRT 37, 311. 12. Бабин, С. -
Cfa in the News ~ Week Ending 3 January 2010
Wolbach Library: CfA in the News ~ Week ending 3 January 2010 1. New social science research from G. Sonnert and co-researchers described, Science Letter, p40, Tuesday, January 5, 2010 2. 2009 in science and medicine, ROGER SCHLUETER, Belleville News Democrat (IL), Sunday, January 3, 2010 3. 'Science, celestial bodies have always inspired humankind', Staff Correspondent, Hindu (India), Tuesday, December 29, 2009 4. Why is Carpenter defending scientists?, The Morning Call, Morning Call (Allentown, PA), FIRST ed, pA25, Sunday, December 27, 2009 5. CORRECTIONS, OPINION BY RYAN FINLEY, ARIZONA DAILY STAR, Arizona Daily Star (AZ), FINAL ed, pA2, Saturday, December 19, 2009 6. We see a 'Super-Earth', TOM BEAL; TOM BEAL, ARIZONA DAILY STAR, Arizona Daily Star, (AZ), FINAL ed, pA1, Thursday, December 17, 2009 Record - 1 DIALOG(R) New social science research from G. Sonnert and co-researchers described, Science Letter, p40, Tuesday, January 5, 2010 TEXT: "In this paper we report on testing the 'rolen model' and 'opportunity-structure' hypotheses about the parents whom scientists mentioned as career influencers. According to the role-model hypothesis, the gender match between scientist and influencer is paramount (for example, women scientists would disproportionately often mention their mothers as career influencers)," scientists writing in the journal Social Studies of Science report (see also ). "According to the opportunity-structure hypothesis, the parent's educational level predicts his/her probability of being mentioned as a career influencer (that ism parents with higher educational levels would be more likely to be named). The examination of a sample of American scientists who had received prestigious postdoctoral fellowships resulted in rejecting the role-model hypothesis and corroborating the opportunity-structure hypothesis. -
Student ID ______TA Name ______Section ______[8 PAGES - 44 QUESTIONS]
Full Name _____________________________________________ Date --12/08/14-- Student ID ____________ TA Name ___________________________________________Section ______ [8 PAGES - 44 QUESTIONS] 1. Here is a series of moon phases, top row, starting with the new moon on November 22, a full moon on December 6, and a new moon on December 22. What does today’s moon phase look like? Choose among those phases labeled “A, B, C, D, or E” – all are labeled December 8, but only 1 is correct. Figure 1. Phases of the Moon from November 22 to December 22, 2014 The phases of the moon progress smoothly. “C” is the correct answer, and if you examine the full moon just above, you will see that “C” is not a perfect circle. Besides, it is just 2 days past the full moon. “B” cannot be right because there are 6 days between the 8th and the 14th when there is a 3rd quarter moon – and the moon takes about 7 days between full and 3rd quarter. 2. No matter where you live on Earth, there is a location that has the same latitude but is 180° away in longitude (on the opposite side of Earth). The next new moon for us is December 22. When is the next new moon for people living on the opposite side of the Earth? a. December 8 (today) b. December 15 c. December 22 d. December 29 3. First, remove Earth’s atmosphere; then, climb to the roof of the UW Tower and drop a hammer and a feather. What is the physical explanation for the objects falling at exactly the same acceleration? a. -
2021 Solar Rituality and Ephemerides
HE LANETARY YSTEM T P S Ideas, Formulas and Forms for a new Culture/Civilization 2021 SOLAR RITUALITY AND EPHEMERIDES (December 2020) [email protected] 1 2021 SOLAR RITUALITY AND EPHEMERIDES A rhythmic and ritual coordination and sowing for a planetary Order The TPS solar Sowing Ia, Fa a F a C a Ca intends to a a a" a aa " a ba a " the cyclic pulsations of the higher Creators, the planetary, solar and cosmic Entities: the conscious Dream of a New Culture and Civilization, as a manifestation on Earth of the evolutionary Plan and of a new human planetary Order.1 By working we learn to work, and in this Workshop of spatial Thought we learn together to build more and more knowingly Harmonic Thought-forms, as a result of a right or heavenly way of being and existing, in order to set up a better Future and to progressively release our humanity from its lower trammels. Humanity can and has to spread, in an impersonal and disinterested way, Seeds or Ideas capable of fertilizing consciousness making it resound to infinity: "Culture is a treasure of consciousness, therefore the field of the sowing of the new Thought is the human consciousness ... It is a vast field like Heaven: no one knows its boundaries. Thus the seeds to be spread have no number or form ... Only with formless seeds an infinite field can be cultivated. And the soil of human consciousness is ready to welcome them: many signs prove it, both above and below, and sowing cannot be deferred". -
The Spinning-Top Be Star Achernar from VLTI-VINCI
A&A 407, L47–L50 (2003) Astronomy DOI: 10.1051/0004-6361:20030786 & c ESO 2003 Astrophysics The spinning-top Be star Achernar from VLTI-VINCI A. Domiciano de Souza1,P.Kervella2,S.Jankov3,L.Abe1, F. Vakili1,3,E.diFolco4, and F. Paresce4 1 Laboratoire Univ. d’Astroph. de Nice (LUAN), CNRS UMR 6525, Parc Valrose, 06108 Nice Cedex 02, France 2 European Southern Observatory (ESO), Alonso de Cordova 3107, Casilla 19001, Vitacura, Santiago 19, Chile 3 Observatoire de la Cˆote d’Azur, D´epartement FRESNEL, CNRS UMR 6528, Boulevard de l’Observatoire, Letter to the Editor BP 4229, 06304 Nice, France 4 European Southern Observatory (ESO), Karl-Schwarzschild str. 2, 85748 Garching, Germany Received 5 May 2003 / Accepted 22 May 2003 Abstract. We report here the first observations of a rapidly rotating Be star, α Eridani, using Earth-rotation synthesis on the Very Large Telescope (VLT) Interferometer. Our measures correspond to a 2a/2b = 1.56 0.05 apparent oblate star, 2a and 2b being the equivalent uniform disc angular diameters in the equatorial and polar direction. Considering± the presence of a circum- stellar envelope (CSE) we argue that our measurement corresponds to a truly distorted star since α Eridani exhibited negligible Hα emission during the interferometric observations. In this framework we conclude that the commonly adopted Roche approx- imation (uniform rotation and centrally condensed mass) should not apply to α Eridani. This result opens new perspectives to basic astrophysical problems, such as rotationally enhanced mass loss and internal angular momentum distribution. In addition to its intimate relation with magnetism and pulsation, rapid rotation thus provides a key to the Be phenomenon: one of the outstanding non-resolved problems in stellar physics. -
FY13 High-Level Deliverables
National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2013 (1 October 2012 – 30 September 2013) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 13 December 2013 Revised 18 September 2014 Contents NOAO MISSION PROFILE .................................................................................................... 1 1 EXECUTIVE SUMMARY ................................................................................................ 2 2 NOAO ACCOMPLISHMENTS ....................................................................................... 4 2.1 Achievements ..................................................................................................... 4 2.2 Status of Vision and Goals ................................................................................. 5 2.2.1 Status of FY13 High-Level Deliverables ............................................ 5 2.2.2 FY13 Planned vs. Actual Spending and Revenues .............................. 8 2.3 Challenges and Their Impacts ............................................................................ 9 3 SCIENTIFIC ACTIVITIES AND FINDINGS .............................................................. 11 3.1 Cerro Tololo Inter-American Observatory ....................................................... 11 3.2 Kitt Peak National Observatory ....................................................................... 14 3.3 Gemini Observatory ........................................................................................ -
The Fundamentals of Stargazing Sky Tours South
The Fundamentals of Stargazing Sky Tours South 01 – The March Sky Copyright © 2014-2016 Mintaka Publishing Inc. www.CosmicPursuits.com -2- The Constellation Orion Let’s begin the tours of the deep-southern sky with the most famous and unmistakable constellation in the heavens, Orion, which will serve as a guide for other bright constellations in the southern late-summer sky. Head outdoors around 8 or 9 p.m. on an evening in early March, and turn towards the north. If you can’t find north, you can ask someone else, or get a small inexpensive compass, or use the GPS in your smartphone or tablet. But you need to face at least generally northward before you can proceed. You will also need a good unobstructed view of the sky in the north, so you may need to get away from structures and trees and so on. The bright stars of the constellation Orion (in this map, south is up and east is to the right) And bring a pair of binoculars if you have them, though they are not necessary for this tour. Fundamentals of Stargazing -3- Now that you’re facing north with a good view of a clear sky, make a 1/8th of a turn to your left. Now you are facing northwest, more or less. Turn your gaze upward about halfway to the point directly overhead. Look for three bright stars in a tidy line. They span a patch of sky about as wide as your three middle fingers held at arm’s length. This is the “belt” of the constellation Orion. -
Introduction to Astronomy Lecture 3: the Birth of Stars and Planets
Introduction to Astronomy Lecture 3: The birth of stars and planets Presented by Dr Helen Johnston School of Physics Spring 2015 The University of Sydney Page In tonight’s lecture • Forming stars – where stars come from • Forming planets – how the planets come together • Measuring stars – how we find the brightness and distance of stars The University of Sydney Page !2 Forming stars Our story begins with the vast clouds of gas between the stars. The University of Sydney The Great Nebula in Orion, M42 Page !4 This gas is made up mostly of hydrogen and helium, formed in the Big Bang. However, a small but vital fraction consists of heavier elements like oxygen, carbon and silicon. As we will see in coming weeks, these elements were manufactured deep in the cores of stars, and returned to the interstellar medium when those stars expired. Without these heavier elements, no rocky planets could form. The Crab Nebula, left behind by the supernovaThe University of Sydney explosion of 1054 AD Page !5 The interstellar material from which the solar system formed consists mostly of hydrogen and helium, with other elements less than one-thousandth as abundant as hydrogen. The “Astronomer’s Periodic table”, with the size of the element indicating its abundance byThe Universityweight. of Sydney (Figure by Ben McCall) Page !6 Star formation takes place in the densest regions of clouds, called dark nebulae. A famous example is the Horsehead Nebula. In these regions, shrouded by dust, molecular gas forms and clumps together and the density increases, until the densest regions start to collapse under their own gravity. -
On the Application of Stark Broadening Data Determined with a Semiclassical Perturbation Approach
Atoms 2014, 2, 357-377; doi:10.3390/atoms2030357 OPEN ACCESS atoms ISSN 2218-2004 www.mdpi.com/journal/atoms Article On the Application of Stark Broadening Data Determined with a Semiclassical Perturbation Approach Milan S. Dimitrijević 1,2,* and Sylvie Sahal-Bréchot 2 1 Astronomical Observatory, Volgina 7, 11060 Belgrade, Serbia 2 Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique, Observatoire de Paris, UMR CNRS 8112, UPMC, 5 Place Jules Janssen, 92195 Meudon Cedex, France; E-Mail: [email protected] (S.S.-B.) * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +381-64-297-8021; Fax: +381-11-2419-553. Received: 5 May 2014; in revised form: 20 June 2014 / Accepted: 16 July 2014 / Published: 7 August 2014 Abstract: The significance of Stark broadening data for problems in astrophysics, physics, as well as for technological plasmas is discussed and applications of Stark broadening parameters calculated using a semiclassical perturbation method are analyzed. Keywords: Stark broadening; isolated lines; impact approximation 1. Introduction Stark broadening parameters of neutral atom and ion lines are of interest for a number of problems in astrophysical, laboratory, laser produced, fusion or technological plasma investigations. Especially the development of space astronomy has enabled the collection of a huge amount of spectroscopic data of all kinds of celestial objects within various spectral ranges. Consequently, the atomic data for trace elements, which had not been -
Final Report the Goddard High Resolution Spectrograph Scientific
NASA-CR-204980 Final Report The Goddard High Resolution Spectrograph Scientific Support Contract NAS5-32494 December 13, 1993 - December 12, 1996 Computer Sciences Corporation 4061 Powder Mill Road Calverton, MD 20705 GHRS SSC Final Report i Contents List of Acronyms iv I. Introduction II. Summary of Activities 4 1 Project Support - Subtask 1 4 1.1 Proposal Preparation and Tracking ..................... 4 1.2 SMOV and Post-COSTAR Calibration ................... 5 1.3 In-Orbit Performance Papers ........................ 7 1.4 Operations Studies .............................. 7 1.4.1 GHRS Efficiency ........................... 7 1.4.2 GHRS Low-Noise Orbits ....................... 8 1.5 Meetings and Information Distribution ................... 9 1.6 Public Information .............................. 9 1.7 The World Wide Web ............................ 10 1.8 The GHRS Science Symposium ....................... 11 2 Data Analysis Facility - Subtask 2 12 2.1 Facility Management ............................. 12 2.2 GHRS Archive ................................ 13 2.3 GHRS Team Software ............................ 15 2.4 General Software Support .......................... 15 2.5 Data Bases .................................. 16 2.6 Data Reduction and Analysis Assistance .................. 17 3 Extragalactic Imagery- Subtask 3 17 3.1 Analysis of R136 ............................... 17 3.2 Eta Carinae .................................. 19 3.3 Star Clusters in M33 ............................. 19 3.3.1 NGC 595 ............................... 20 3.3,2