Close Binary White Dwarf Systems: Numerous New Detections and Their Interpretation
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Astronomy Lab Manual
MSE2151 Astronomy Laboratory – Stars Lab Manual Department of Astrophysics & Planetary Science Villanova University Spring 2020 Lab Schedule MSE2151: Astronomy Laboratory – Stars Spring 2020 Week 1: Lab A – Working with Numbers, Graphs, & the Computer ASSIGNED AS A TAKE-HOME LAB Week 2: Lab B – Energy Transport in Stars Week 3: Lab C – Introduction to Spectroscopy Week 4: Lab D – Introduction to Optics Week 5: Lab E – Building a Galileoscope Week 6: Lab F – Classification of Stellar Spectra Week 7: Lab G – Effects of the Atmosphere on Astronomical Observations Week 8: Lab H – Taking a Star’s Temperature Week 9: Lab I – Trigonometric Parallax Week 10: Lab J – The Distance to a Star Cluster Week 11: Lab K – Measuring the Mass of the Andromeda Galaxy Week 12: Lab L – Expansion of the Universe Week 13: MAKEUP LAB Observing sessions for the “Observatory Lab” will be scheduled throughout the semester. Spring 2020 Mendel Science Experience 2151 Astronomy Laboratory - Stars Observatory Lab The Villanova Public Observatory PURPOSE: The science of astronomy began with the first humans who looked up into the nighttime sky and wondered “What’s going on up there?” This semester, you will explore some of the answers to this question in your lecture course and in this lab course. Most of this exploration will happen in the classroom or in the lab room. This lab will give you the opportunity to go outside and actually look at the nighttime sky, using both the unaided eye and a powerful modern astronomical telescope. EQUIPMENT: The Villanova Public Observatory, accessible via the Department of Astrophysics & Planetary Science on the 4th floor of Mendel Science Center. -
Interstellar Deuterium, Nitrogen, and Oxygen Abundances Toward BD-T-28:' 4211: Results from the Far Ultraviolet Spectroscopic Explorer I
Interstellar Deuterium, Nitrogen, and Oxygen Abundances Toward BD-t-28:' 4211: Results from the Far Ultraviolet Spectroscopic Explorer I George Sonneborn, 2 Martial Andre, 3 Cristina Oliveira, a Guillaume H_brard, 4 J. Christopher Howk, s Todd M. Tripp, 5 Pierre Chayer, a'6 Scott D. Friedman, 3 Jeffrey W. Kruk, 3 Edward B. Jenkins, 5 Martin Lemoine, 4 H. Warren Moos, 3 William R. Oegerle, 2 Kenneth R. Sembach, s and Alfred Vidal-Madjar 4 ABSTRACT High resolution far-ultra_ iolet spectra of the O-type subdwarf BD +28 ° 4211 were obtained with the Far Ultraviolet Spe(troscopic Explorer to measure the interstellar deuterium, nitrogen, and oxygen abundances in tMs direction. The interstellar D I transitions are analyzed down to Ly_ at 920.7 A. The star was observed several times at different target offsets in the direction of spectral dispersion. The :digned and coadded spectra have high signal-to-noise ratios (S/N -- 50 - 100). D I, N I, and O I transitions were analyzed with curve-of-growth and profile fitting techniques. A model of inter_tellar molecular hydrogen on the line of sight was derived from H2 lines in the FUSE spectra altd used to help analyze some features where blending with H2 was significant. The H I columr, density was determined from high resolution HST/STIS spectra of Lya to be log N(H I) = 19.846 4- 0.035 (2a), which is higher than is typical for sight lines in the local ISM studied for D/H. We found that D/H = (1.39 + 0.21) x 10 -5 (2a) and O/H = (2.37 4- 0.55) x 10-4 (2a). -
Kinematik Weißer Zwerge Und Heißer, Unterleuchtkräftiger Sterne
Kinematik Weißer Zwerge und heißer, unterleuchtkräftiger Sterne Diplomarbeit vorgelegt von Roland Bernhard Josef Richter Dr. Remeis-Sternwarte Bamberg Astronomisches Institut der Universität Erlangen-Nürnberg Sternwartstraße 7, 96049 Bamberg Betreuer: Prof. Dr. U. Heber 27. Oktober 2006 Inhaltsverzeichnis 5.5.2 Klassifikation 0 Einleitung 5.5.3 Das Alter der DB Weißen Zwerge 1 Die Messobjekte dieser Arbeit 5.6 DA Weiße Zwerge, die nicht im SPY 1.1 Die Weißen Zwerge Katalog waren. 1.2 Die unterleuchtkräftigen Sterne 5.7 Verhältnis zwischen DB und DA Weißen 1.3 Die Milchstraße, unsere Galaxie Zwergen 1.4 Die Rotation der Milchstraße 5.8 Ist WD0255-705 aus der dünnen Scheibe 2 Populationen der Sterne ausgetreten? 2.1 Das galaktische Koordinatensystem 5.9 Vergleich meiner Arbeit mit Paulis 2.2 Daten zu den Populationen Weißen Zwergen (nur DA) 3 Kinematische Kriterien zur Klassifikation 5.10 Statistik aller DA Weißen Zwerge 3.1 Kalibrierung nach Pauli 5.11 Vergleich mit theoretischen Halo-Dichten 3.2 Galaktische Orbits 6 Heiße unterleuchtkräftige Sterne 3.3 Geschwindigkeitsdiagramme von (subdwarfs (sd)) galaktischen Orbits 6.1 Auswahl der unterleuchtkräftigen Sterne 3.3.1 V-U Diagramm 6.2 Unterschiede zu Weißen Zwergen in der 3.3.2 Toomre Diagramm Kinematik 3.4 e-J z Diagramm 6.3 Ergebnisse der kinematischen 3.5 Gesamtklassifikation Untersuchung der unterleuchtkräftigen 4 Physikalische Eigenschaften und ihre Sterne Bestimmung 6.3.1 Die Position der sdB Sterne in der 4.1 Radialgeschwindigkeit Milchstraße 4.2 Temperatur und Schwerebeschleunigung -
Download This Article in PDF Format
A&A 589, A58 (2016) Astronomy DOI: 10.1051/0004-6361/201527970 & c ESO 2016 Astrophysics High-resolution Imaging of Transiting Extrasolar Planetary systems (HITEP) I. Lucky imaging observations of 101 systems in the southern hemisphere?,?? D. F. Evans1, J. Southworth1, P. F. L. Maxted1, J. Skottfelt2; 3, M. Hundertmark3, U. G. Jørgensen3, M. Dominik4, K. A. Alsubai5, M. I. Andersen6, V. Bozza7; 8, D. M. Bramich5, M. J. Burgdorf9, S. Ciceri10, G. D’Ago11, R. Figuera Jaimes4; 12, S.-H. Gu13; 14, T. Haugbølle3, T. C. Hinse15, D. Juncher3, N. Kains16, E. Kerins17, H. Korhonen18; 3, M. Kuffmeier3, L. Mancini10, N. Peixinho19; 20, A. Popovas3, M. Rabus21; 10, S. Rahvar22, R. W. Schmidt23, C. Snodgrass24, D. Starkey4, J. Surdej25, R. Tronsgaard26, C. von Essen26, Yi-Bo Wang13; 14, and O. Wertz25 (Affiliations can be found after the references) Received 15 December 2015 / Accepted 9 March 2016 ABSTRACT Context. Wide binaries are a potential pathway for the formation of hot Jupiters. The binary fraction among host stars is an important discrim- inator between competing formation theories, but has not been well characterised. Additionally, contaminating light from unresolved stars can significantly affect the accuracy of photometric and spectroscopic measurements in studies of transiting exoplanets. Aims. We observed 101 transiting exoplanet host systems in the Southern hemisphere in order to create a homogeneous catalogue of both bound companion stars and contaminating background stars, in an area of the sky where transiting exoplanetary systems have not been systematically searched for stellar companions. We investigate the binary fraction among the host stars in order to test theories for the formation of hot Jupiters. -
Heavy Element Abundances in DAO White Dwarfs Measured from FUSE Data
Mon. Not. R. Astron. Soc. 000, 1–15 (2004) Printed 23 June 2005 (MN LaTEX style file v2.2) Heavy element abundances in DAO white dwarfs measured from FUSE data ½ ½ ½ ¾ S.A. Good½ , M.A. Barstow , M.R. Burleigh , P.D. Dobbie , J.B. Holberg and I. Hubeny ¿ ½ Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH ¾ Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA ¿ Steward Observatory and Department of Astronomy, University of Arizona, Tucson, AZ 85721, USA Released 2002 Xxxxx XX ABSTRACT We present heavy element abundance measurements for 16 DAO white dwarfs, determined from Far-Ultraviolet Spectroscopic Explorer (FUSE) spectra. Evidence of absorption by heavy elements was found in the spectra of all the objects. Measurements were made us- ing models that adopted the temperatures, gravities and helium abundances determined from both optical and FUSE data by Good et al. (2004). It was found that, when using the values for those parameters measured from optical data, the carbon abundance measurements follow and extend a similar trend of increasing abundance with temperature for DA white dwarfs, discovered by Barstow et al. (2003). However, when the FUSE measurements are used the DAO abundances no longer join this trend since the temperatures are higher than the opti- cal measures. Silicon abundances were found to increase with temperature, but no similar trend was identified in the nitrogen, oxygen, iron or nickel abundances, and no dependence on gravity or helium abundances were noted. However, the models were not able to reproduce the observed silicon and iron line strengths satisfactorily in the spectra of half the objects, and the oxygen features of all but three. -
IUE References from 1978 Until June 2001
IUE REFERENCES from 1978 until June 2001 ¾ ½;4 J. Fernley ½ , P. Pitts , M. Barylak ¿ ¿ ¿ R. Gonzalez-Riestra´ ¿ ,E.Solano ,A.Talavera ,F.Rodr´ıguez ½ ESA IUE Observatory, PO Box 50727, 28080 Madrid, Spain ¾ NASA GSFC, Greenbelt, Maryland ¿ Laboratorio de Astrof´ısica Espacial y F´ısica Fundamental PO Box 50727, 28080 Madrid, Spain 4 Affiliated with the Astrophysics Division, Space Science Department ESTEC, the Netherlands We have compiled a list of references to IUE publications covering the period from 1978 until June 2001. This compilation is based upon earlier works of Mead et al. (1986), Pitts (1991) and our own. The IUE satellite has provided the scientific community with over 110,000 UV spectra which are now in the public domain. Prospective user of these IUE data are provided with a list that holds a total of 3776 IUE papers from the following journals: Journal Abbreviation Nr. Astronomical Journal AJ 200 Astronomy and Astrophysics A&A 982 Astronomy and Astrophysics Supplement A&AS 94 Astrophysical Journal APJ 1513 Astrophysical Journal Supplement APJS 112 Astrophysics and Space Science AP&SS 69 Advances in Space Research ASR 3 Geophysical Research Letters GRL 10 Irish Astronomical Journal IAJ 2 Icarus ICARUS 56 Journal of Geophysical Research JGR 19 Monthly Notices of the Royal Astr. Soc. MNRAS 410 Nature NATURE 53 Proceedings of the National Academy of Sience PNAS 2 Proceedings Astron. Soc. of Australia PASA 3 Publications Astron. Soc. of Japan PASJ 6 Publications of the Astron.Soc.of Pacific PASP 167 Revista Mexicana de Astronomia y Astrofisica RMAA 18 Science SCIENCE 2 Others (BAIC, M&P, RSPT, etc.) 55 Total 3776 We trust that this compilation is useful although we have not added other publications like meeting abstracts, conference proceedings, or other popular articles. -
Programme (Talks, Pdf)
NATO Advanced Research Workshop on WHITE DWARFS Scientific Programme Monday 24 June 08:30-09:00 Registration 09:00-09:10 Welcome to the NATO ARW - 13th European Workshop on White Dwarfs Session 1: White Dwarf Structure and Evolution (Chair: Gerard Vauclair) 09:10 09:30 Volker Weidemann On Oxygen/Neon White Dwarfs 09:30-09:50 Oscar Straniero Progenitors evolution and chemical stratification of CO white dwarfs Convective Coupling: A Largely Overlooked Effect in the 09:50-10:10 Gilles Fontaine Cooling of White Dwarfs Ne22 Sedimentation in Liquid White Interiors: Cooling and 10:10-10:30 Christopher Deloye Seismological Impact 10:30-10:50 Detlef Schönberner From red giants to white dwarfs: a hydrodynamical simulation of the planetary nebula stage 10:50-11:20 Coffee break Session 2: SNIa Progenitors (Chair: Pierre Maxted) 11:20-11:40 Enrico Cappellaro Supernova Ia: constraints for the progenitor scenarios CO WDs accreting CO-rich matter: the lifting effect of 11:40-12:00 Luciano Piersanti rotation 12:00-12:20 Ralf Napiwotzki Search for progenitors of SN Ia 12:20-12:40 Christian Karl 'SPY'ing on double degenerates 12:40-14:10 LUNCH Session 3: Subdwarf B stars (Chair:Elizabeth Green) 14:10-14:30 Uli Heber On the progenitors of helium core white dwarfs 14:30-14:50 Simon Jeffery The progeny of binary white dwarf mergers; extreme helium stars, R CrB stars and subdwarf B stars 14:50-15:10 Luisa Morales-Rueda Twenty three new subdwarf periods The results of diffusion calculations with mass loss in 15:10-15:30 Klaus Unglaub subdwarf B stars and comparison -
Optical Observatories
NATIONAL OPTICAL ASTRONOMY OBSERVATORIES NATIONAL OPTICAL ASTRONOMY OBSERVATORIES Cerro Tololo Inter-American Observatory Kitt Peak National Observatory National Solar Observatory La Serena, Chile Tucson, Arizona 85726 Sunspot, New Mexico 88349 ANNUAL REPORT October 1993 - September 1994 November 10, 1994 TABLE OF CONTENTS I. INTRODUCTION n. AURA BOARD m. SCIENTIFIC PROGRAM Cerro Tololo Inter-American Observatory (CTIO) 1. A Hubble Diagram of Distant Type la Supernovae 2. The Stellar Populations of the Carina Dwarf Galaxy 3 3. Observations of the Collision ofComet Shoemaker-Levy 9 and Jupiter 4 B. Kitt Peak National Observatory (KPNO) 5 1. Faint Galaxy Halo Could Trace Dark Matter 5 2. Young Stellar Objects in Bok Globules 5 3. A New Tool for Stellar Population Studies 6 C. National Solar Observatory (NSO) 7 1. New Observations of IR Coronal Emission Lines 7 2. High Resolution Infrared Spectroscopy of the Carbon Monoxide Molecule 7 3. Subsurface Magnetic Flux Tubes 8 IV. DIVISION OPERATIONS 9 A. Cerro Tololo Inter-American Observatory 9 1. 4-m Telescope Image Quality Improvements 9 2. Infrared Instrumentation 10 3. Arcon CCD Controllers 10 4. Other Projects 11 B. Kitt Peak National Observatory 11 1. New KPNO Programs in FY 1994 11 2. KPNO Facilities Improvements in FY 1994 13 3. KPNO Instrumentation 14 C. National Solar Observatory 17 1. Image Quality Improvement Program for NSO Telescopes 17 2. Sac Peak Instrumentation 18 3. Tucson Instrumentation 20 D. US Gemini Program 21 E. NOAO Instrumentation Program 22 V. MAJOR PROJECTS 23 A. Global Oscillation Network Group Project 23 B. The Precision Solar Photometric Telescope Project (PSPT) 25 C.