Books on Variable Stars - Storm Dunlop 17 BAA Journal Papers on Variable Stars 19 Fadars - Dr David Pike 22 Ζ Aurigae Binary Stars - Dr R.F
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Explore the Universe Observing Certificate Second Edition
RASC Observing Committee Explore the Universe Observing Certificate Second Edition Explore the Universe Observing Certificate Welcome to the Explore the Universe Observing Certificate Program. This program is designed to provide the observer with a well-rounded introduction to the night sky visible from North America. Using this observing program is an excellent way to gain knowledge and experience in astronomy. Experienced observers find that a planned observing session results in a more satisfying and interesting experience. This program will help introduce you to amateur astronomy and prepare you for other more challenging certificate programs such as the Messier and Finest NGC. The program covers the full range of astronomical objects. Here is a summary: Observing Objective Requirement Available Constellations and Bright Stars 12 24 The Moon 16 32 Solar System 5 10 Deep Sky Objects 12 24 Double Stars 10 20 Total 55 110 In each category a choice of objects is provided so that you can begin the certificate at any time of the year. In order to receive your certificate you need to observe a total of 55 of the 110 objects available. Here is a summary of some of the abbreviations used in this program Instrument V – Visual (unaided eye) B – Binocular T – Telescope V/B - Visual/Binocular B/T - Binocular/Telescope Season Season when the object can be best seen in the evening sky between dusk. and midnight. Objects may also be seen in other seasons. Description Brief description of the target object, its common name and other details. Cons Constellation where object can be found (if applicable) BOG Ref Refers to corresponding references in the RASC’s The Beginner’s Observing Guide highlighting this object. -
M-53 Ngc – 5053
MONTHLY OBSERVER’S CHALLENGE Las Vegas Astronomical Society Compiled by: Roger Ivester, Boiling Springs, North Carolina & Fred Rayworth, Las Vegas, Nevada With special assistance from: Rob Lambert, Las Vegas, Nevada JUNE 2014 Messier 53 (M53)/NGC-5053 – Globular Cluster Pair In Coma Berenices Introduction The purpose of the observer’s challenge is to encourage the pursuit of visual observing. It is open to everyone that is interested, and if you are able to contribute notes, drawings, or photographs, we will be happy to include them in our monthly summary. Observing is not only a pleasure, but an art. With the main focus of amateur astronomy on astrophotography, many times people tend to forget how it was in the days before cameras, clock drives, and GOTO. Astronomy depended on what was seen through the eyepiece. Not only did it satisfy an innate curiosity, but it allowed the first astronomers to discover the beauty and the wonderment of the night sky. Before photography, all observations depended on what the astronomer saw in the eyepiece, and how they recorded their observations. This was done through notes and drawings and that is the tradition we are stressing in the observers challenge. By combining our visual observations with our drawings, and sometimes, astrophotography (from those with the equipment and talent to do so), we get a unique understanding of what it is like to look through an eyepiece, and to see what is really there. The hope is that you will read through these notes and become inspired to take more time at the eyepiece studying each object, and looking for those subtle details that you might never have noticed before. -
Arxiv:2006.10868V2 [Astro-Ph.SR] 9 Apr 2021 Spain and Institut D’Estudis Espacials De Catalunya (IEEC), C/Gran Capit`A2-4, E-08034 2 Serenelli, Weiss, Aerts Et Al
Noname manuscript No. (will be inserted by the editor) Weighing stars from birth to death: mass determination methods across the HRD Aldo Serenelli · Achim Weiss · Conny Aerts · George C. Angelou · David Baroch · Nate Bastian · Paul G. Beck · Maria Bergemann · Joachim M. Bestenlehner · Ian Czekala · Nancy Elias-Rosa · Ana Escorza · Vincent Van Eylen · Diane K. Feuillet · Davide Gandolfi · Mark Gieles · L´eoGirardi · Yveline Lebreton · Nicolas Lodieu · Marie Martig · Marcelo M. Miller Bertolami · Joey S.G. Mombarg · Juan Carlos Morales · Andr´esMoya · Benard Nsamba · KreˇsimirPavlovski · May G. Pedersen · Ignasi Ribas · Fabian R.N. Schneider · Victor Silva Aguirre · Keivan G. Stassun · Eline Tolstoy · Pier-Emmanuel Tremblay · Konstanze Zwintz Received: date / Accepted: date A. Serenelli Institute of Space Sciences (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E- 08193, Spain and Institut d'Estudis Espacials de Catalunya (IEEC), Carrer Gran Capita 2, Barcelona, E-08034, Spain E-mail: [email protected] A. Weiss Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany C. Aerts Institute of Astronomy, Department of Physics & Astronomy, KU Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium and Department of Astrophysics, IMAPP, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands G.C. Angelou Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany D. Baroch J. C. Morales I. Ribas Institute of· Space Sciences· (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E-08193, arXiv:2006.10868v2 [astro-ph.SR] 9 Apr 2021 Spain and Institut d'Estudis Espacials de Catalunya (IEEC), C/Gran Capit`a2-4, E-08034 2 Serenelli, Weiss, Aerts et al. -
Orbits and Pulsations of the Classical Aurigae Binaries
The Astrophysical Journal, 679:1490Y1498, 2008 June 1 A # 2008. The American Astronomical Society. All rights reserved. Printed in U.S.A. ORBITS AND PULSATIONS OF THE CLASSICAL AURIGAE BINARIES Joel A. Eaton,1 Gregory W. Henry,1 and Andrew P. Odell2 Received 2007 October 12; accepted 2008 January 23 ABSTRACT We have derived new orbits for Aur, 32 Cyg, and 31 Cyg with observations from the Tennessee State University (TSU) Automatic Spectroscopic Telescope, and used them to identify nonorbital velocities of the cool supergiant components of these systems. We measure periods in those deviations, identify unexpected long-period changes in the radial velocities, and place upper limits on the rotation of these stars. These radial-velocity variations are not obviously consistent with radial pulsation theory, given what we know about the masses and sizes of the components. Our concurrent photometry detected the nonradial pulsations driven by tides (ellipsoidal variation) in both Aur and 32 Cyg, at a level and phasing roughly consistent with simple theory to first order, although they seem to require moderately large gravity darkening. However, the K component of 32 Cyg must be considerably bigger than ex- pected, or have larger gravity darkening than Aur, to fit its amplitude. However, again there is precious little evi- dence for the normal radial pulsation of cool stars in our photometry. H shows some evidence for chromospheric heating by the B component in both Aur and 32 Cyg, and the three stars show among them a meager 2Y3 outbursts in their winds of the sort seen occasionally in cool supergiants. -
Index to JRASC Volumes 61-90 (PDF)
THE ROYAL ASTRONOMICAL SOCIETY OF CANADA GENERAL INDEX to the JOURNAL 1967–1996 Volumes 61 to 90 inclusive (including the NATIONAL NEWSLETTER, NATIONAL NEWSLETTER/BULLETIN, and BULLETIN) Compiled by Beverly Miskolczi and David Turner* * Editor of the Journal 1994–2000 Layout and Production by David Lane Published by and Copyright 2002 by The Royal Astronomical Society of Canada 136 Dupont Street Toronto, Ontario, M5R 1V2 Canada www.rasc.ca — [email protected] Table of Contents Preface ....................................................................................2 Volume Number Reference ...................................................3 Subject Index Reference ........................................................4 Subject Index ..........................................................................7 Author Index ..................................................................... 121 Abstracts of Papers Presented at Annual Meetings of the National Committee for Canada of the I.A.U. (1967–1970) and Canadian Astronomical Society (1971–1996) .......................................................................168 Abstracts of Papers Presented at the Annual General Assembly of the Royal Astronomical Society of Canada (1969–1996) ...........................................................207 JRASC Index (1967-1996) Page 1 PREFACE The last cumulative Index to the Journal, published in 1971, was compiled by Ruth J. Northcott and assembled for publication by Helen Sawyer Hogg. It included all articles published in the Journal during the interval 1932–1966, Volumes 26–60. In the intervening years the Journal has undergone a variety of changes. In 1970 the National Newsletter was published along with the Journal, being bound with the regular pages of the Journal. In 1978 the National Newsletter was physically separated but still included with the Journal, and in 1989 it became simply the Newsletter/Bulletin and in 1991 the Bulletin. That continued until the eventual merger of the two publications into the new Journal in 1997. -
A Survey of Active Galaxies at Tev Photon Energies with the HAWC Gamma-Ray Observatory
Draft version September 22, 2020 Typeset using LATEX default style in AASTeX63 A survey of active galaxies at TeV photon energies with the HAWC gamma-ray observatory A. Albert,1 C. Alvarez,2 J.R. Angeles Camacho,3 J.C. Arteaga-Velazquez,´ 4 K.P. Arunbabu,5 D. Avila Rojas,3 H.A. Ayala Solares,6 V. Baghmanyan,7 E. Belmont-Moreno,3 S.Y. BenZvi,8 C. Brisbois,9 K.S. Caballero-Mora,2 T. Capistran´ ,10 A. Carraminana~ ,10 S. Casanova,7 U. Cotti,4 J. Cotzomi,11 S. Coutino~ de Leon´ ,10 E. De la Fuente,12 B.L. Dingus,1 M.A. DuVernois,13 M. Durocher,1 J.C. D´ıaz-Velez´ ,12 K. Engel,9 C. Espinoza,3 K.L. Fan,9 M. Fernandez´ Alonso,6 H. Fleischhack,14 N. Fraija,15 A. Galvan-G´ amez,´ 15 D. Garc´ıa,3 J.A. Garc´ıa-Gonzalez´ ,3 F. Garfias,15 M.M. Gonzalez´ ,15 J.A. Goodman,9 J.P. Harding,1 S. Hernandez´ ,3 B. Hona,14 D. Huang,14 F. Hueyotl-Zahuantitla,2 P. Huntemeyer,¨ 14 A. Iriarte,15 A. Jardin-Blicq,16, 17, 18 V. Joshi,19 D. Kieda,20 G.J. Kunde,1 A. Lara,5 W.H. Lee,15 H. Leon´ Vargas,3 J.T. Linnemann,21 A.L. Longinotti,10 G. Luis-Raya,22 J. Lundeen,21 K. Malone,1 O. Mart´ınez,11 I. Martinez-Castellanos,9 J. Mart´ınez-Castro,23 J.A. Matthews,24 P. Miranda-Romagnoli,25 J.A. Morales-Soto,4 E. Moreno,11 M. -
The Structures and Extents of the Chromospheres of Late-Type Stars
The Structures and Extents of the Chromospheres of Late-type Stars A dissertation submitted to the University of Dublin for the degree of Doctor of Philosophy Neal O´ Riain Trinity College Dublin, September 2015 School of Physics University of Dublin Trinity College Declaration I declare that this thesis has not been submitted as an exercise for a degree at this or any other university and it is entirely my own work. I agree to deposit this thesis in the University's open access institu- tional repository or allow the library to do so on my behalf, subject to Irish Copyright Legislation and Trinity College Library conditions of use and acknowledgement. Name: Neal O´ Riain Signature: ........................................ Date: .......................... Summary The chromosphere is the region of a star, above what is traditionally defined as the stellar surface, from which photons freely escape. As the definition implies, this region is characterised by complexity, non- equilibrium, and specifying its structure is a vastly non-linear, non- local problem. In this work we are concerned with the chromospheres of late-type stars, objects of spectral type K to M, the thermodynamic structure, extent, and heating mechanisms of whose chromospheres are not well understood. We use a number of observational and computa- tional methods in order to gain a detailed quantitative understanding of these chromospheres. We construct a model to compute the mm, thermal bremsstrahlung flux from the chromospheres of late-type objects, based on a number of simplifying assumptions concerning their thermodynamic structure. We compare this model with archival and recent observations, and find that the model is capable of reproducing the observed flux from objects of spectral type K to mid-M in the frequency range 100 GHz { 350 GHz. -
Arxiv:1108.4369V1
THE ASTROPHYSICAL JOURNAL, 2011, IN PRESS Preprint typeset using LATEX style emulateapj v. 03/07/07 TESTING A PREDICTIVE THEORETICAL MODEL FOR THE MASS LOSS RATES OF COOL STARS STEVEN R. CRANMER AND STEVEN H. SAAR Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 Draft version February 7, 2018 ABSTRACT The basic mechanisms responsible for producing winds from cool, late-type stars are still largely unknown. We take inspiration from recent progress in understanding solar wind acceleration to develop a physically motivated model of the time-steady mass loss rates of cool main-sequence stars and evolved giants. This model follows the energy flux of magnetohydrodynamic turbulence from a subsurface convection zone to its eventual dissipation and escape through open magnetic flux tubes. We show how Alfvén waves and turbulence can produce winds in either a hot corona or a cool extended chromosphere, and we specify the conditions that determine whether or not coronal heating occurs. These models do not utilize arbitrary normalization factors, but instead predict the mass loss rate directly from a star’s fundamental properties. We take account of stellar magnetic activity by extending standard age-activity-rotation indicators to include the evolution of the filling factor of strong photospheric magnetic fields. We compared the predicted mass loss rates with observed values for 47 stars and found significantly better agreement than was obtained from the popular scaling laws of Reimers, Schröder, and Cuntz. The algorithm used to compute cool-star mass loss rates is provided as a self-contained and efficient computer code. We anticipate that the results from this kind of model can be incorporated straightforwardly into stellar evolution calculations and population synthesis techniques. -
January 2015, Vol. 26, No.1 Newsletter
\M The Newsletter of the Cape Cod Astronomical Society January, 2015 Vol. 26 No. 1 Happy New Year !! Start the New Year right by planning with the Staff of The Schmidt Observatory to watch the shadows of three of Jupiter’s moons cross the planet a bit after midnight on Saturday, Jan 24, 2015! If you can only take one look, observe at 1:40am to see the amazing sight at left (image is “true”.) From left to right on the surface of Jupiter: Callisto above the shadow of Europa, Callisto shadow, Io, Io’s shadow (not shown: Europa to left of the planet.) If the “seeing is good” all three shadows should be visible using our 16” or 18” ‘scopes; the moons themselves will be tougher to see against the planet’s surface. 1-24 1:4(0 The earlier view at 10pm on Friday: Ganymede is far far to left, Europa, then Callisto, then Io lined up at lower left of the planet; ingress: Callisto Shad at 10:11, Io Shad at 11:35, Io at 11:55, Callisto at 1:19am, Europa Shad at 1:28am; Io’s shadow, the first to go, leaves at 1:52am. The three near moons all “off surface” at lower right of right of planet by 6am. Enjoy !! Next Monthly Meeting: is Thursday, January 8th at 7:30pm. Mike Hunter, CCAS member and past president, will speak on Choices: Some Intended, Some Unexpected...a look at the choices unpaid astronomers are faced with in viewing/imaging the sun and sky…and the consequences, known and unknown, of those choices. -
Models for Sixty Double-Lined Binaries Containing Giants
Mon. Not. R. Astron. Soc. 000, 000–000 (2016) Printed 17 November 2016 (MN LATEX style file v2.2) Models for Sixty Double-Lined Binaries containing Giants Peter P. Eggleton1⋆ Kadri Yakut2 1 Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, CA94551, USA 2 Department of Astronomy & Space Sciences, University of Ege, 35100, Bornova–Izmir,˙ Turkey Received ABSTRACT The observed masses, radii and temperatures of 60 medium- to long-period binaries, most of which contain a cool, evolved star and a hotter less-evolved one, are compared with theoretical models which include (a) core convective overshooting, (b) mass loss, possibly driven by dynamo action as in RS CVn binaries, and (c) tidal friction, in- cluding its effect on orbital period through magnetic braking. A reasonable fit is found in about 42 cases, but in 11 other cases the primaries appear to have lost either more mass or less mass than the models predict, and in 4 others the orbit is predicted to be either more or less circular than observed. Of the remaining 3 systems, two (γ Per and HR 8242) have a markedly ‘over-evolved’ secondary, our explanation being that the primary component is the merged remnant of a former short-period sub-binary in a former triple system. The last system (V695 Cyg) defies any agreement at present. Mention is also made of three other systems (V643 Ori, OW Gem and V453 Cep), which are relevant to our discussion. Key words: Stellar evolution – binaries – composite-spectrum binaries 1 INTRODUCTION be more like 10% than 3%. One such study was made by Schr¨oder et al. -
International Astronomical Union Commission 42 BIBLIOGRAPHY
International Astronomical Union Commission 42 BIBLIOGRAPHY OF CLOSE BINARIES No. 74 Editor-in-Chief: C.D. Scarfe Editors: H. Drechsel D.R. Faulkner V.G. Karetnikov E. Lapasset C. Maceroni Y. Nakamura P.G. Niarchos R.G. Samec W. Van Hamme M. Wolf Material published by March 15, 2002 BCB issues are available via URL: http://www.sternwarte.uni-erlangen.de/ftp/bcb or via anonymous ftp from: ftp://www.sternwarte.uni-erlangen.de/pub/bcb This issue is also available via URL: http://www.astro.washington.edu/szkody/c42/ The bibliographical entries for Individual Stars and Collections of Data are categorized according to the following coding scheme: 1. Observational data a. Photometry b. Spectroscopy c. Spectrophotometry d. Polarimetry e. Astrometry, interferometry f. Times of minima g. γ-ray data i. Infrared data o. Optical data p. Photographic data r. Radio data u. Ultraviolet data v. Visual estimates x. X-ray data 2. Derived physical data a. Orbital elements b. Absolute dimensions, masses c. New or improved ephemeris, period variations d. Apsidal motion e. Physical properties of stellar atmospheres f. Chemical abundances g. Accretion disks and accretion phenomena 3. Catalogues, discoveries, charts a. Catalogues b. Discoveries of new binaries and novae c. Identification of optical counterparts of X-ray, IR, or radio sources d. Finding charts 4. Observational techniques 5. Theoretical investigations 6. Statistical investigations 7. Miscellaneous a. Abstract b. Addenda or errata Abbreviations AD accretion disk HMXB high-mass x-ray binary QPO quasi-periodic oscillation BH black hole IP intermediate polar RV radial velocity CB close binary LC light curve SB spectroscopic binary CV cataclysmic variable LMXB low-mass x-ray binary WD white dwarf EB eclipsing binary NS neutron star WR Wolf-Rayet star Several entries of this issue use the abbreviation: OAP | Odessa Astronomical Publications (issue of the Odessa Astronomical Observatory of the Odessa State University, Ukraine), Astroprint Publishing Company, Ukraine Individual Stars Z And Kilpio, E.Y. -
Brightest Stars : Discovering the Universe Through the Sky's Most Brilliant Stars / Fred Schaaf
ffirs.qxd 3/5/08 6:26 AM Page i THE BRIGHTEST STARS DISCOVERING THE UNIVERSE THROUGH THE SKY’S MOST BRILLIANT STARS Fred Schaaf John Wiley & Sons, Inc. flast.qxd 3/5/08 6:28 AM Page vi ffirs.qxd 3/5/08 6:26 AM Page i THE BRIGHTEST STARS DISCOVERING THE UNIVERSE THROUGH THE SKY’S MOST BRILLIANT STARS Fred Schaaf John Wiley & Sons, Inc. ffirs.qxd 3/5/08 6:26 AM Page ii This book is dedicated to my wife, Mamie, who has been the Sirius of my life. This book is printed on acid-free paper. Copyright © 2008 by Fred Schaaf. All rights reserved Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada Illustration credits appear on page 272. Design and composition by Navta Associates, Inc. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600, or on the web at www.copy- right.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permissions.