Chapter 11: Variable Stars, Light Curves & Periodicity
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II Publications, Presentations
II Publications, Presentations 1. Refereed Publications Izumi, K., Kotake, K., Nakamura, K., Nishida, E., Obuchi, Y., Ohishi, N., Okada, N., Suzuki, R., Takahashi, R., Torii, Abadie, J., et al. including Hayama, K., Kawamura, S.: 2010, Y., Ueda, A., Yamazaki, T.: 2010, DECIGO and DECIGO Search for Gravitational-wave Inspiral Signals Associated with pathfinder, Class. Quantum Grav., 27, 084010. Short Gamma-ray Bursts During LIGO's Fifth and Virgo's First Aoki, K.: 2010, Broad Balmer-Line Absorption in SDSS Science Run, ApJ, 715, 1453-1461. J172341.10+555340.5, PASJ, 62, 1333. Abadie, J., et al. including Hayama, K., Kawamura, S.: 2010, All- Aoki, K., Oyabu, S., Dunn, J. P., Arav, N., Edmonds, D., Korista sky search for gravitational-wave bursts in the first joint LIGO- K. T., Matsuhara, H., Toba, Y.: 2011, Outflow in Overlooked GEO-Virgo run, Phys. Rev. D, 81, 102001. Luminous Quasar: Subaru Observations of AKARI J1757+5907, Abadie, J., et al. including Hayama, K., Kawamura, S.: 2010, PASJ, 63, S457. Search for gravitational waves from compact binary coalescence Aoki, W., Beers, T. C., Honda, S., Carollo, D.: 2010, Extreme in LIGO and Virgo data from S5 and VSR1, Phys. Rev. D, 82, Enhancements of r-process Elements in the Cool Metal-poor 102001. Main-sequence Star SDSS J2357-0052, ApJ, 723, L201-L206. Abadie, J., et al. including Hayama, K., Kawamura, S.: 2010, Arai, A., et al. including Yamashita, T., Okita, K., Yanagisawa, TOPICAL REVIEW: Predictions for the rates of compact K.: 2010, Optical and Near-Infrared Photometry of Nova V2362 binary coalescences observable by ground-based gravitational- Cyg: Rebrightening Event and Dust Formation, PASJ, 62, wave detectors, Class. -
Is the Universe Expanding?: an Historical and Philosophical Perspective for Cosmologists Starting Anew
Western Michigan University ScholarWorks at WMU Master's Theses Graduate College 6-1996 Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew David A. Vlosak Follow this and additional works at: https://scholarworks.wmich.edu/masters_theses Part of the Cosmology, Relativity, and Gravity Commons Recommended Citation Vlosak, David A., "Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew" (1996). Master's Theses. 3474. https://scholarworks.wmich.edu/masters_theses/3474 This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact [email protected]. IS THEUN IVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STAR TING ANEW by David A Vlasak A Thesis Submitted to the Faculty of The Graduate College in partial fulfillment of the requirements forthe Degree of Master of Arts Department of Philosophy Western Michigan University Kalamazoo, Michigan June 1996 IS THE UNIVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STARTING ANEW David A Vlasak, M.A. Western Michigan University, 1996 This study addresses the problem of how scientists ought to go about resolving the current crisis in big bang cosmology. Although this problem can be addressed by scientists themselves at the level of their own practice, this study addresses it at the meta level by using the resources offered by philosophy of science. There are two ways to resolve the current crisis. -
The Agb Newsletter
THE AGB NEWSLETTER An electronic publication dedicated to Asymptotic Giant Branch stars and related phenomena Official publication of the IAU Working Group on Abundances in Red Giants No. 208 — 1 November 2014 http://www.astro.keele.ac.uk/AGBnews Editors: Jacco van Loon, Ambra Nanni and Albert Zijlstra Editorial Dear Colleagues, It is our pleasure to present you the 208th issue of the AGB Newsletter. The variety of topics is, as usual, enormous, though post-AGB phases feature prominently, as does R Scuti this time. Don’t miss the announcements of the Olivier Chesneau Prize, and of three workshops to keep you busy and entertained over the course of May–July next year. We look forward to receiving your reactions to this month’s Food for Thought (see below)! The next issue is planned to be distributed around the 1st of December. Editorially Yours, Jacco van Loon, Ambra Nanni and Albert Zijlstra Food for Thought This month’s thought-provoking statement is: What is your favourite AGB star, RSG, post-AGB object, post-RSG or PN? And why? Reactions to this statement or suggestions for next month’s statement can be e-mailed to [email protected] (please state whether you wish to remain anonymous) 1 Refereed Journal Papers Evolutionary status of the active star PZ Mon Yu.V. Pakhomov1, N.N. Chugai1, N.I. Bondar2, N.A. Gorynya1,3 and E.A. Semenko4 1Institute of Astronomy, Russian Academy of Sciences, Pyatnitskaya 48, 119017, Moscow, Russia 2Crimean Astrophysical Observatory, Nauchny, Crimea, 2984009, Russia 3Lomonosov Moscow State University, Sternberg Astronomical Institute, Universitetskij prospekt, 13, Moscow 119991, Russia 4Special Astrophysical Observatory of Russian Academy of Sciences, Russia We use original spectra and available photometric data to recover parameters of the stellar atmosphere of PZ Mon, formerly referred as an active red dwarf. -
Information Bulletin on Variable Stars
COMMISSIONS AND OF THE I A U INFORMATION BULLETIN ON VARIABLE STARS Nos November July EDITORS L SZABADOS K OLAH TECHNICAL EDITOR A HOLL TYPESETTING K ORI ADMINISTRATION Zs KOVARI EDITORIAL BOARD L A BALONA M BREGER E BUDDING M deGROOT E GUINAN D S HALL P HARMANEC M JERZYKIEWICZ K C LEUNG M RODONO N N SAMUS J SMAK C STERKEN Chair H BUDAPEST XI I Box HUNGARY URL httpwwwkonkolyhuIBVSIBVShtml HU ISSN COPYRIGHT NOTICE IBVS is published on b ehalf of the th and nd Commissions of the IAU by the Konkoly Observatory Budap est Hungary Individual issues could b e downloaded for scientic and educational purp oses free of charge Bibliographic information of the recent issues could b e entered to indexing sys tems No IBVS issues may b e stored in a public retrieval system in any form or by any means electronic or otherwise without the prior written p ermission of the publishers Prior written p ermission of the publishers is required for entering IBVS issues to an electronic indexing or bibliographic system to o CONTENTS C STERKEN A JONES B VOS I ZEGELAAR AM van GENDEREN M de GROOT On the Cyclicity of the S Dor Phases in AG Carinae ::::::::::::::::::::::::::::::::::::::::::::::::::: : J BOROVICKA L SAROUNOVA The Period and Lightcurve of NSV ::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::: W LILLER AF JONES A New Very Long Period Variable Star in Norma ::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::::: EA KARITSKAYA VP GORANSKIJ Unusual Fading of V Cygni Cyg X in Early November ::::::::::::::::::::::::::::::::::::::: -
Variable Star Classification and Light Curves Manual
Variable Star Classification and Light Curves An AAVSO course for the Carolyn Hurless Online Institute for Continuing Education in Astronomy (CHOICE) This is copyrighted material meant only for official enrollees in this online course. Do not share this document with others. Please do not quote from it without prior permission from the AAVSO. Table of Contents Course Description and Requirements for Completion Chapter One- 1. Introduction . What are variable stars? . The first known variable stars 2. Variable Star Names . Constellation names . Greek letters (Bayer letters) . GCVS naming scheme . Other naming conventions . Naming variable star types 3. The Main Types of variability Extrinsic . Eclipsing . Rotating . Microlensing Intrinsic . Pulsating . Eruptive . Cataclysmic . X-Ray 4. The Variability Tree Chapter Two- 1. Rotating Variables . The Sun . BY Dra stars . RS CVn stars . Rotating ellipsoidal variables 2. Eclipsing Variables . EA . EB . EW . EP . Roche Lobes 1 Chapter Three- 1. Pulsating Variables . Classical Cepheids . Type II Cepheids . RV Tau stars . Delta Sct stars . RR Lyr stars . Miras . Semi-regular stars 2. Eruptive Variables . Young Stellar Objects . T Tau stars . FUOrs . EXOrs . UXOrs . UV Cet stars . Gamma Cas stars . S Dor stars . R CrB stars Chapter Four- 1. Cataclysmic Variables . Dwarf Novae . Novae . Recurrent Novae . Magnetic CVs . Symbiotic Variables . Supernovae 2. Other Variables . Gamma-Ray Bursters . Active Galactic Nuclei 2 Course Description and Requirements for Completion This course is an overview of the types of variable stars most commonly observed by AAVSO observers. We discuss the physical processes behind what makes each type variable and how this is demonstrated in their light curves. Variable star names and nomenclature are placed in a historical context to aid in understanding today’s classification scheme. -
Gaia Data Release 2 Special Issue
A&A 623, A110 (2019) Astronomy https://doi.org/10.1051/0004-6361/201833304 & © ESO 2019 Astrophysics Gaia Data Release 2 Special issue Gaia Data Release 2 Variable stars in the colour-absolute magnitude diagram?,?? Gaia Collaboration, L. Eyer1, L. Rimoldini2, M. Audard1, R. I. Anderson3,1, K. Nienartowicz2, F. Glass1, O. Marchal4, M. Grenon1, N. Mowlavi1, B. Holl1, G. Clementini5, C. Aerts6,7, T. Mazeh8, D. W. Evans9, L. Szabados10, A. G. A. Brown11, A. Vallenari12, T. Prusti13, J. H. J. de Bruijne13, C. Babusiaux4,14, C. A. L. Bailer-Jones15, M. Biermann16, F. Jansen17, C. Jordi18, S. A. Klioner19, U. Lammers20, L. Lindegren21, X. Luri18, F. Mignard22, C. Panem23, D. Pourbaix24,25, S. Randich26, P. Sartoretti4, H. I. Siddiqui27, C. Soubiran28, F. van Leeuwen9, N. A. Walton9, F. Arenou4, U. Bastian16, M. Cropper29, R. Drimmel30, D. Katz4, M. G. Lattanzi30, J. Bakker20, C. Cacciari5, J. Castañeda18, L. Chaoul23, N. Cheek31, F. De Angeli9, C. Fabricius18, R. Guerra20, E. Masana18, R. Messineo32, P. Panuzzo4, J. Portell18, M. Riello9, G. M. Seabroke29, P. Tanga22, F. Thévenin22, G. Gracia-Abril33,16, G. Comoretto27, M. Garcia-Reinaldos20, D. Teyssier27, M. Altmann16,34, R. Andrae15, I. Bellas-Velidis35, K. Benson29, J. Berthier36, R. Blomme37, P. Burgess9, G. Busso9, B. Carry22,36, A. Cellino30, M. Clotet18, O. Creevey22, M. Davidson38, J. De Ridder6, L. Delchambre39, A. Dell’Oro26, C. Ducourant28, J. Fernández-Hernández40, M. Fouesneau15, Y. Frémat37, L. Galluccio22, M. García-Torres41, J. González-Núñez31,42, J. J. González-Vidal18, E. Gosset39,25, L. P. Guy2,43, J.-L. Halbwachs44, N. C. Hambly38, D. -
Stars and Their Spectra: an Introduction to the Spectral Sequence Second Edition James B
Cambridge University Press 978-0-521-89954-3 - Stars and Their Spectra: An Introduction to the Spectral Sequence Second Edition James B. Kaler Index More information Star index Stars are arranged by the Latin genitive of their constellation of residence, with other star names interspersed alphabetically. Within a constellation, Bayer Greek letters are given first, followed by Roman letters, Flamsteed numbers, variable stars arranged in traditional order (see Section 1.11), and then other names that take on genitive form. Stellar spectra are indicated by an asterisk. The best-known proper names have priority over their Greek-letter names. Spectra of the Sun and of nebulae are included as well. Abell 21 nucleus, see a Aurigae, see Capella Abell 78 nucleus, 327* ε Aurigae, 178, 186 Achernar, 9, 243, 264, 274 z Aurigae, 177, 186 Acrux, see Alpha Crucis Z Aurigae, 186, 269* Adhara, see Epsilon Canis Majoris AB Aurigae, 255 Albireo, 26 Alcor, 26, 177, 241, 243, 272* Barnard’s Star, 129–130, 131 Aldebaran, 9, 27, 80*, 163, 165 Betelgeuse, 2, 9, 16, 18, 20, 73, 74*, 79, Algol, 20, 26, 176–177, 271*, 333, 366 80*, 88, 104–105, 106*, 110*, 113, Altair, 9, 236, 241, 250 115, 118, 122, 187, 216, 264 a Andromedae, 273, 273* image of, 114 b Andromedae, 164 BDþ284211, 285* g Andromedae, 26 Bl 253* u Andromedae A, 218* a Boo¨tis, see Arcturus u Andromedae B, 109* g Boo¨tis, 243 Z Andromedae, 337 Z Boo¨tis, 185 Antares, 10, 73, 104–105, 113, 115, 118, l Boo¨tis, 254, 280, 314 122, 174* s Boo¨tis, 218* 53 Aquarii A, 195 53 Aquarii B, 195 T Camelopardalis, -
Carbon Stars T. Lloyd Evans
J. Astrophys. Astr. (2010) 31, 177–211 Carbon Stars T. Lloyd Evans SUPA, School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9SS, UK. e-mail: [email protected] Received 2010 July 19; accepted 2010 October 18 Abstract. In this paper, the present state of knowledge of the carbon stars is discussed. Particular attention is given to issues of classification, evolution, variability, populations in our own and other galaxies, and circumstellar material. Key words. Stars: carbon—stars: evolution—stars: circumstellar matter —galaxies: magellanic clouds. 1. Introduction Carbon stars have been reviewed on several previous occasions, most recently by Wallerstein & Knapp (1998). A conference devoted to this topic was held in 1996 (Wing 2000) and two meetings on AGB stars (Le Bertre et al. 1999; Kerschbaum et al. 2007) also contain much on carbon stars. This review emphasizes develop- ments since 1997, while paying particular attention to connections with earlier work and to some of the important sources of concepts. Recent and ongoing develop- ments include surveys for carbon stars in more of the galaxies of the local group and detailed spectroscopy and infrared photometry for many of them, as well as general surveys such as 2MASS, AKARI and the Sirius near infrared survey of the Magel- lanic Clouds and several dwarf galaxies, the Spitzer-SAGE mid-infrared survey of the Magellanic Clouds and the current Herschel infrared satellite project. Detailed studies of relatively bright galactic examples continue to be made by high-resolution spectroscopy, concentrating on abundance determinations using the red spectral region, and infrared and radio observations which give information on the history of mass loss. -
N95- 27078 13 Discussion on Selected Symbiotic Stars
N95- 27078 13 DISCUSSION ON SELECTED SYMBIOTIC STARS R. Viotti and M. Hack I. INTRODUCTION made of its variations" (Mayall, 1969). This pessimistic remark should be consid- Because of its large variety of aspects, the ered as a note of caution for those involved in symbiotic phenomenon is not very suitable for the interpretation of the observations. In the a statistical treatment. It is also not clear following, we shall discuss a number of indi- whether symbiotic stars really represent a vidual symbiotic stars for which the amount of homogeneous group of astrophysical objects or observational data is large enough to draw a a collection of objects of different natures but rather complete picture of their general behav- showing similar phenomena. However, as al- ior and to make consistent models. We shall ready discussed in the introduction to the sym- especially illustrate the necessary steps toward biotic stars, in this monograph we are espe- an empirical model and take the discussion of cially interested in the symbiotic phenomenon, the individual objects as a useful occasion to i.e., in those physical processes occurring in describe different techniques of diagnosis. the atmosphere of each individual object and in their time dependence. Such a research can be I1. Z ANDROMEDAE AND THE DIAGNOS- performed through the detailed analysis of TICS OF THE SYMBIOTIC STARS individual objects. This study should be done for a time long enough to cover all the different II.A. INTRODUCTION phases of their activity, in all the spectral ranges. Since the typical time scale of the symbiotic phenomena is up to several years and Z And has been considered as the prototype decades, this represents a problem since, for of the symbiotic stars, from its light history and instance, making astronomy outside the visual the spectral variation during outburst. -
Variable Star
Variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) fluctuates. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as either: Intrinsic variables, whose luminosity actually changes; for example, because the star periodically swells and shrinks. Extrinsic variables, whose apparent changes in brightness are due to changes in the amount of their light that can reach Earth; for example, because the star has an orbiting companion that sometimes Trifid Nebula contains Cepheid variable stars eclipses it. Many, possibly most, stars have at least some variation in luminosity: the energy output of our Sun, for example, varies by about 0.1% over an 11-year solar cycle.[1] Contents Discovery Detecting variability Variable star observations Interpretation of observations Nomenclature Classification Intrinsic variable stars Pulsating variable stars Eruptive variable stars Cataclysmic or explosive variable stars Extrinsic variable stars Rotating variable stars Eclipsing binaries Planetary transits See also References External links Discovery An ancient Egyptian calendar of lucky and unlucky days composed some 3,200 years ago may be the oldest preserved historical document of the discovery of a variable star, the eclipsing binary Algol.[2][3][4] Of the modern astronomers, the first variable star was identified in 1638 when Johannes Holwarda noticed that Omicron Ceti (later named Mira) pulsated in a cycle taking 11 months; the star had previously been described as a nova by David Fabricius in 1596. This discovery, combined with supernovae observed in 1572 and 1604, proved that the starry sky was not eternally invariable as Aristotle and other ancient philosophers had taught. -
Variable Star Section Circular
British Astronomical Association VARIABLE STAR SECTION CIRCULAR No 112, June 2002 Contents Light Curves for some Eclipsing Binary Stars .............................. inside covers From the Director ............................................................................................. 1 Change in E-mail Address for Computer Secretary ......................................... 1 Letters ............................................................................................................... 2 Information on Photometry Available .............................................................. 2 Change to September Circular Deadline .......................................................... 2 The Fade of UY Cen ........................................................................................ 3 Meauring Times of Minimum of EBs using a CCD camera ............................ 4 Photometric Calibration of an MX516 CCD Camera ...................................... 7 Recent Papers on Variable Stars .................................................................... 14 IBVS............................................................................................................... 15 Eclipsing Binary Predictions .......................................................................... 18 ISSN 0267-9272 Office: Burlington House, Piccadilly, London, W1V 9AG PRELIMINARY ECLIPSING BINARY LIGHT CURVES TONY MARKHAM Here are some light curves showing the recent behaviour of some Eclipsing Binaries. The light curves for RZ Cas, Beta -
Chapter 5 Misaligned Spin Axes in the DI Herculis System
Stars and planets at high spatial and spectral resolution Albrecht, S. Citation Albrecht, S. (2008, December 17). Stars and planets at high spatial and spectral resolution. Retrieved from https://hdl.handle.net/1887/13359 Version: Corrected Publisher’s Version Licence agreement concerning inclusion of doctoral thesis in the License: Institutional Repository of the University of Leiden Downloaded from: https://hdl.handle.net/1887/13359 Note: To cite this publication please use the final published version (if applicable). Chapter 5 Misaligned spin axes in the DI Herculis system DI Herculis is one of the most interesting young eclipsing binary systems known. Its apsidal motion, the rotation of the orbit in its own plane, has been measured to be significantly lower (2.9 × 10−4 ± 0.4 · 10−4 ◦/cycle) than the expected value (1.25 · 10−3 ◦/cycle). Until now the reason why its apsidal motion is much slower than theoretically expected escapes a solid explanation. A number of theories have been put forward to explain this apparent discrepancy, including a revision of general relativity. However the underlying calculations are based on the premise of co-aligned stellar rotation axes. To test this assumption we observed the DI Herculis system during both primary and secondary eclipse with the high resolution Echelle spectrograph Sophie of the Oberserva- torie de Haute Provence. Using our newly developed analysis tools (Chapter 4) we find a strong misalignment be- tween the projections of the stellar spin axes and the orbital spin axis on the sky. The angle between, the projected stellar spin axes and the projected orbital spin axis is (71 ± 4◦) for the primary and (93 ± 8◦) for the secondary.