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The AAVSO DSLR Observing Manual
The AAVSO DSLR Observing Manual AAVSO 49 Bay State Road Cambridge, MA 02138 email: [email protected] Version 1.2 Copyright 2014 AAVSO Foreword This manual is a basic introduction and guide to using a DSLR camera to make variable star observations. The target audience is first-time beginner to intermediate level DSLR observers, although many advanced observers may find the content contained herein useful. The AAVSO DSLR Observing Manual was inspired by the great interest in DSLR photometry witnessed during the AAVSO’s Citizen Sky program. Consumer-grade imaging devices are rapidly evolving, so we have elected to write this manual to be as general as possible and move the software and camera-specific topics to the AAVSO DSLR forums. If you find an area where this document could use improvement, please let us know. Please send any feedback or suggestions to [email protected]. Most of the content for these chapters was written during the third Citizen Sky workshop during March 22-24, 2013 at the AAVSO. The persons responsible for creation of most of the content in the chapters are: Chapter 1 (Introduction): Colin Littlefield, Paul Norris, Richard (Doc) Kinne, Matthew Templeton Chapter 2 (Equipment overview): Roger Pieri, Rebecca Jackson, Michael Brewster, Matthew Templeton Chapter 3 (Software overview): Mark Blackford, Heinz-Bernd Eggenstein, Martin Connors, Ian Doktor Chapters 4 & 5 (Image acquisition and processing): Robert Buchheim, Donald Collins, Tim Hager, Bob Manske, Matthew Templeton Chapter 6 (Transformation): Brian Kloppenborg, Arne Henden Chapter 7 (Observing program): Des Loughney, Mike Simonsen, Todd Brown Various figures: Paul Valleli Clear skies, and Good Observing! Arne Henden, Director Rebecca Turner, Operations Director Brian Kloppenborg, Editor Matthew Templeton, Science Director Elizabeth Waagen, Senior Technical Assistant American Association of Variable Star Observers Cambridge, Massachusetts June 2014 i Index 1. -
Highlights of Discoveries for $\Delta $ Scuti Variable Stars from the Kepler
Highlights of Discoveries for δ Scuti Variable Stars from the Kepler Era Joyce Ann Guzik1,∗ 1Los Alamos National Laboratory, Los Alamos, NM 87545 USA Correspondence*: Joyce Ann Guzik [email protected] ABSTRACT The NASA Kepler and follow-on K2 mission (2009-2018) left a legacy of data and discoveries, finding thousands of exoplanets, and also obtaining high-precision long time-series data for hundreds of thousands of stars, including many types of pulsating variables. Here we highlight a few of the ongoing discoveries from Kepler data on δ Scuti pulsating variables, which are core hydrogen-burning stars of about twice the mass of the Sun. We discuss many unsolved problems surrounding the properties of the variability in these stars, and the progress enabled by Kepler data in using pulsations to infer their interior structure, a field of research known as asteroseismology. Keywords: Stars: δ Scuti, Stars: γ Doradus, NASA Kepler Mission, asteroseismology, stellar pulsation 1 INTRODUCTION The long time-series, high-cadence, high-precision photometric observations of the NASA Kepler (2009- 2013) [Borucki et al., 2010; Gilliland et al., 2010; Koch et al., 2010] and follow-on K2 (2014-2018) [Howell et al., 2014] missions have revolutionized the study of stellar variability. The amount and quality of data provided by Kepler is nearly overwhelming, and will motivate follow-on observations and generate new discoveries for decades to come. Here we review some highlights of discoveries for δ Scuti (abbreviated as δ Sct) variable stars from the Kepler mission. The δ Sct variables are pre-main-sequence, main-sequence (core hydrogen-burning), or post-main-sequence (undergoing core contraction after core hydrogen burning, and beginning shell hydrogen burning) stars with spectral types A through mid-F, and masses around 2 solar masses. -
Annual Report 2016–2017 AAVSO
AAVSO The American Association of Variable Star Observers Annual Report 2016–2017 AAVSO Annual Report 2012 –2013 The American Association of Variable Star Observers AAVSO Annual Report 2016–2017 The American Association of Variable Star Observers 49 Bay State Road Cambridge, MA 02138-1203 USA Telephone: 617-354-0484 Fax: 617-354-0665 email: [email protected] website: https://www.aavso.org Annual Report Website: https://www.aavso.org/annual-report On the cover... At the 2017 AAVSO Annual Meeting.(clockwise from upper left) Knicole Colon, Koji Mukai, Dennis Conti, Kristine Larsen, Joey Rodriguez; Rachid El Hamri, Andy Block, Jane Glanzer, Erin Aadland, Jamin Welch, Stella Kafka; and (clockwise from upper left) Joey Rodriguez, Knicole Colon, Koji Mukai, Frans-Josef “Josch” Hambsch, Chandler Barnes. Picture credits In additon to images from the AAVSO and its archives, the editors gratefully acknowledge the following for their image contributions: Glenn Chaple, Shawn Dvorak, Mary Glennon, Bill Goff, Barbara Harris, Mario Motta, NASA, Gary Poyner, Msgr. Ronald Royer, the Mary Lea Shane Archives of the Lick Observatory, Chris Stephan, and Wheatley, et al. 2003, MNRAS, 345, 49. Table of Contents 1. About the AAVSO Vision and Mission Statement 1 About the AAVSO 1 What We Do 2 What Are Variable Stars? 3 Why Observe Variable Stars? 3 The AAVSO International Database 4 Observing Variable Stars 6 Services to Astronomy 7 Education and Outreach 9 2. The Year in Review Introduction 11 The 106th AAVSO Spring Membership Meeting, Ontario, California 11 The -
A Spectroscopic Study of Pulsations in Γ Doradus Stars
A SPECTROSCOPIC STUDY OF PULSATIONS IN γ DORADUS STARS THOMAS ROBERT SHUTT MSc by Research University of York Physics March 2018 ii ABSTRACT Two candidate γ Doradus stars are analysed: HD 103257 and HD 109799. Over 250 spectra were gathered for analysis using the HERCULES spectrograph at the University of Canterbury Mt John Observatory. The spectra for each star were cross-correlated with synthetic spectra to produce line profiles and augmented with photometric data from the WASP archive and HIPPARCOS catalogue for frequency and mode analysis. Three pulsation frequencies were identified for HD 103257: 1.22496 ± 0.00001 d−1 , 1.14569 ± 0.00002 d−1 and 0.67308 ± 0.00004 d−1, explaining 66.6% of the variation across the line profiles. The frequencies were characterised with best-fit modes of (ℓ, m) = (1, 1), (1, 1) and (3, -2) respectively. The inclination of the rotation axis and the radius were −1 best-fit to i = 86.4° and R = 2.6 푅⊙, while a zero-point fit yielded a vsini of 71.5 km s . Three pulsation frequencies were identified for HD 109799: 1.48679 ± 0.00002 d−1 , 1.25213 ± 0.00002 d−1 and 0.92184 ± 0.00004 d−1 , explaining 39.3% of the variation across the line profiles. The frequencies yielded individual mode fits of modes (ℓ, m) = (1, 1), (1, 1) and (3, 2). The rotational axis for HD 109799 to the range i = 65° - 70° with a zero- point fitted vsini of 40.2 km s−1. Based on observations of frequencies and modes characteristic of the class, HD 103257 and HD 109799 can now be categorised as bona fide γ Doradus stars. -
CCD Photometry, Light Curve Deconvolution, Period Analysis, Kinematics, and Evolutionary Status of the HADS Variable V460 Andromedae
Alton and Stępień, JAAVSO Volume 47, 2019 53 CCD Photometry, Light Curve Deconvolution, Period Analysis, Kinematics, and Evolutionary Status of the HADS Variable V460 Andromedae Kevin B. Alton UnderOak and Desert Bloom Observatories, 70 Summit Avenue, Cedar Knolls, NJ 07927; [email protected] Kazimierz Stępień Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland Received March 3, 2019; revised April 8, 2019; accepted April 8, 2019 Abstract Multi-color (BVIc) CCD-derived photometric data were acquired from V460 And, an intrinsic variable classically defined as a High Amplitude delta Scuti (HADS) type system. Deconvolution of precise time-series light curve data was accomplished –1 using discrete Fourier transformation and revealed a fundamental mode ( f0 ) of oscillation at ~13.336 d along with five other partial harmonics (2f0 –6f0 ). No other statistically significant frequencies were resolved following successive pre-whitening of each residual signal. An assessment of potential period changes over time was performed using six new times-of-maximum light produced from the present study along with other values reported in the literature. These along with sparsely-sampled data collected during the ROTSE-I (1999), Catalina Sky (2005–2013), and SuperWASP (2004–2008) surveys indicate that no substantive change in the primary pulsation period or amplitude (V-mag) has likely occurred over the past 20 years. Recent photometric data from space telescopes have in some cases contradicted traditional classification schemes and clouded the differences between HADS- and SX Phe-like variables. Herein using accurate cosmic distances and proper motions from Gaia DR2, we attempted to exploit potential kinematic differences between established populations of HADS and SX Phe variable stars as an alternate approach for classification. -
High-Frequency A-Type Pulsators Discovered Using Superwasp †
MNRAS 439, 2078–2095 (2014) doi:10.1093/mnras/stu094 Advance Access publication 2014 February 17 High-frequency A-type pulsators discovered using SuperWASP † Daniel L. Holdsworth,1‡ B. Smalley,1 M. Gillon,2 K. I. Clubb,3 J. Southworth,1 P. F. L. Maxted,1 D. R. Anderson,1 S. C. C. Barros,4 A. Collier Cameron,5 L. Delrez,2 F. Faedi,6 C. A. Haswell,7 C. Hellier,1 K. Horne,5 E. Jehin,2 A. J. Norton,7 D. Pollacco,6 I. Skillen,8 A. M. S. Smith,9 R. G. West6 andP.J.Wheatley6 1Astrophysics Group, Keele University, Staffordshire ST5 5BG, UK 2Institut d’Astrophysique et de Geophysique,´ UniversitedeLi´ ege,` Alleedu6Ao´ ut,ˆ 17, Bat. B5C, Liege` 1, Belgium 3Department of Astronomy, University of California, Berkeley, CA 94720-3411, USA 4Aix-Marseille Universite,´ CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, F-13388 Marseille, France 5SUPA, School of Physics & Astronomy, University of St. Andrews, North Haugh, Fife KY16 9SS, UK 6Department of Physics, University of Warwick, Coventry CV4 7AL, UK 7Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK 8Isaac Newton Group of Telescopes, Apartado de Correos 321, E-38700 Santa Cruz de la Palma, Tenerife, Spain Downloaded from 9N. Copernicus Astronomical Centre, Polish Academy of Sciences, Bartycka 18, PL-00-716 Warsaw, Poland Accepted 2014 January 13. Received 2014 January 10; in original form 2013 December 20 http://mnras.oxfordjournals.org/ ABSTRACT We present the results of a survey using the WASP archive to search for high-frequency pulsations in F-, A- and B-type stars. -
The Omegawhite Survey for Short-Period Variable Stars I: Overview and First Results
Mon. Not. R. Astron. Soc. 000, 1{15 (2015) Printed 12 September 2018 (MN LaTEX style file v2.2) The OmegaWhite Survey for Short-Period Variable Stars I: Overview and First Results S.A Macfarlane1;2?, R. Toma3, G. Ramsay3, P.J Groot1, P.A Woudt2, J.E Drew4, G. Barentsen4, J. Eisl¨offel5, 1Department of Astrophysics/IMAPP, Radboud University, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands 2Astrophysics,Cosmology and Gravity Centre, Department of Astronomy, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa 3Armagh Observatory, College Hill, Armagh, BT61 9DG, Northern Ireland 4School of Physics, Astronomy & Mathematics, University of Hertfordshire, College Lane, Hatfield, Hertfordshire, AL10 9AB, U.K. 5Th¨uringerLandessternwarte, Sternwarte 5, D-07778 Tautenburg, Germany 12 September 2018 ABSTRACT We present the goals, strategy and first results of the OmegaWhite survey: a wide- field high-cadence g-band synoptic survey which aims to unveil the Galactic population of short-period variable stars (with periods < 80 min), including ultracompact binary star systems and stellar pulsators. The ultimate goal of OmegaWhite is to cover 400 square degrees along the Galactic Plane reaching a depth of g = 21.5 mag (10σ), using OmegaCam on the VLT Survey Telescope (VST). The fields are selected to overlap with surveys such as the Galactic Bulge Survey (GBS) and the VST Photometric Hα Survey of the Southern Galactic Plane (VPHAS+) for multi-band colour information. Each field is observed using 38 exposures of 39 s each, with a median cadence of ∼2.7 min for a total duration of two hours. -
A Collection of Curricula for the STARLAB Constellation Cylinder
A Collection of Curricula for the STARLAB Constellation Cylinder Including: Constellation Identification by Science First/STARLAB. A Look at the Constellations Cylinder by Joyce Kloncz Stories in the Stars by Gary D. Kratzer ©2008 by Science First/STARLAB, 95 Botsford Place, Buffalo, NY 14216. www.starlab.com. All rights reserved. Curriculum Guide Contents Constellation Identification .......................................3 Cancer (The Crab) ...........................................13 Alphabetical Listing of Constellations ........................3 Centaurus (The Centaur) ...................................14 Northern Celestial Pole Constellations .......................4 Corvus (The Crow) ..........................................14 Cassiopeia .......................................................4 Hydra (The Water Snake) .................................14 Cepheus ...........................................................4 Leo (The Lion) ..................................................15 Draco (The Dragon) ...........................................4 Lupus (The Wolf) ..............................................15 Ursa Major (The Great Bear) ..............................5 Virgo (The Virgin) ............................................15 Ursa Minor (The Little Bear) .................................5 Summer Constellations ..........................................17 Autumn Constellations .............................................6 Aquila (The Eagle) ...........................................17 Andromeda (Andromeda) ..................................6 -
Analysis of a Short Periodic Pulsator: Sx Phoenicis Star
Revista Mexicana de Astronom´ıay Astrof´ısica, 56, 287{294 (2020) c 2020: Instituto de Astronom´ıa,Universidad Nacional Aut´onomade M´exico https://doi.org/10.22201/ia.01851101p.2020.56.02.10 ANALYSIS OF A SHORT PERIODIC PULSATOR: SX PHOENICIS STAR XX CYG Mohamed Abdel-Sabour1, Ahmed Shokry1, and Ahmed Ibrahim2,3 Received May 5 2020; accepted August 7 2020 ABSTRACT Photometric observations were made of the SX Phoenicis star XX Cyg be- tween September and October 2019, using the 1.88-m Kottamia reflector telescope in Egypt. We used 340 CCD observations with blue-visible-red (BVR) filters to derive light curves. In addition, we obtained 9540 visual magnitudes for XX Cyg from the literature to prepare an observed-minus-calculated (O-C) diagram. 85 new times of maximum for XX Cyg are presented. We did not detect a bump in the descending portion of the light curve of maximum light for XX Cyg. How- ever, we did detect a secular bump in the phased light curves, which changes with phase in some SuperWASP observations. We found the change in period of XX Cyg to be dP /dt = 15.5×10−5 s/yr, with its amplitude decreasing at a rate of 0.7 mmag/year. Stellar parameters of XX Cyg and its position in the instability strip of the Hertzsprung Russell stellar evolution diagram are presented. RESUMEN Se realizaron observaciones fotom´etricas de la estrella tipo SX Phoeni- cis XX Cyg entre septiembre y octubre de 2019 con el telescopio de 1.88 m Kottamia, en Egipto. -
Multi-Color Photometry of the Hot R Coronae Borealis Star, MV Sagittarii
Volume 45 Number 2 JAAVSO 2017 The Journal of the American Association of Variable Star Observers Multi-color Photometry of the Hot R Coronae Borealis Star, MV Sagittarii Visual AAVSO database magnitudes plus V photoelectric and CCD magnitudes for MV Sgr. Black color coding indicates AAVSO data, red photoelectric data, green CCD data, and blue two photoelectric possible MV Sgr data points. Also in this issue... • New Observations of AD Serpentis • Amplitude Variations in Pulsating Red Giants. II. Some Systematics • Studies of the Long Secondary Periods in Pulsating Red Giants. II. Lower-Luminosity Stars • Improving the Photometric Calibration of the Enigmatic Star KIC 8462852 Complete table of contents inside... The American Association of Variable Star Observers 49 Bay State Road, Cambridge, MA 02138, USA The Journal of the American Association of Variable Star Observers Editor John R. Percy Kosmas Gazeas Kristine Larsen Dunlap Institute of Astronomy University of Athens Department of Geological Sciences, and Astrophysics Athens, Greece Central Connecticut State University, and University of Toronto New Britain, Connecticut Toronto, Ontario, Canada Edward F. Guinan Villanova University Vanessa McBride Associate Editor Villanova, Pennsylvania IAU Office of Astronomy for Development; Elizabeth O. Waagen South African Astronomical Observatory; John B. Hearnshaw and University of Cape Town, South Africa Production Editor University of Canterbury Michael Saladyga Christchurch, New Zealand Ulisse Munari INAF/Astronomical Observatory Laszlo L. Kiss of Padua Editorial Board Konkoly Observatory Asiago, Italy Geoffrey C. Clayton Budapest, Hungary Louisiana State University Nikolaus Vogt Baton Rouge, Louisiana Katrien Kolenberg Universidad de Valparaiso Universities of Antwerp Valparaiso, Chile Zhibin Dai and of Leuven, Belgium Yunnan Observatories and Harvard-Smithsonian Center David B. -
Manual for Visual Observing of Variable Stars
A AVS O Manual for Visual Observing of Variable Stars Revised Edition March 2013 The American Association of Variable Star Observers 49 Bay State Road Cambridge, Massachusetts 02138 U. S. A. Tel: 617-354-0484 Fax: 617-354-0665 Email: [email protected] Web: https://www.aavso.org Copyright 2013 by the American Association of Variable Star Observers 49 Bay State Road Cambridge, MA 02138 U. S. A. ISBN 978-1-878174-00-0 ii FOREWORD TO 2013 EDITION It is with great pleasure that we present this revised and improved edition of the Manual for Visual Observing of Variable Stars. This manual is intended to be a comprehensive guide to variable star observing. This manual provides up-to-date information for making variable star observations and reporting them to the AAVSO, and was written by visual observing experts. For new observers, this manual is an essential tool—the one place from which one can gather all the information needed in order to start a variable star observing program. Long-time and experienced observers, and those returning to variable star observing, on the other hand, may find it useful as a ready- reference, quick-resource, or refresher text to help explore new aspects of variable star observing. This manual will familiarize you with the standardized processes and procedures of variable star observing—a very important part of making and submitting your observations to the AAVSO. You will find here new information, presented in a useful format, with chapters grouped by subject- matter. There are several pull-out pages for those who prefer to put essential information in their own observing notebooks or under a plastic sleeve.