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Appearance of Special UGSU-Type Phenomenon in the Light Curve of UGZ White Dwarf Nova RX Andromedae

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Volume 44 Number 1 JAAVSO 2016 The Journal of the American Association of Variable Star Observers Appearance of Special UGSU-Type Phenomenon in the Light Curve of UGZ White Dwarf Nova RX Andromedae RX And superoutburst at JD 2456987. The superoutburst of about 10.7 magnitude is superpositioned on the precursor normal outburst of about 11.0 magnitude. Also in this issue... • Long-term Radial Velocity Monitoring of the HeI 6678 Line of ζ Tauri • Monitoring the Continuing Spectral Evolution of Nova Delphini 2013 (V339 Del) with Low Resolution Spectroscopy • Intermittent Multi-color Photometry for V1017 Sagittarii 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 Edward F. Guinan Paula Szkody Dunlap Institute of Astronomy Villanova University University of Washington and Astrophysics Villanova, Pennsylvania Seattle, Washington and University of Toronto Toronto, Ontario, Canada John B. Hearnshaw Nikolaus Vogt University of Canterbury Universidad de Valparaiso Associate Editor Christchurch, New Zealand Valparaiso, Chile Elizabeth O. Waagen Laszlo L. Kiss Douglas L. Welch Production Editor Konkoly Observatory McMaster University Michael Saladyga Budapest, Hungary Hamilton, Ontario, Canada Katrien Kolenberg David B. Williams Editorial Board Universities of Antwerp Whitestown, Indiana Geoffrey C. Clayton and of Leuven, Belgium Louisiana State University and Harvard-Smithsonian Center Thomas R. Williams Baton Rouge, Louisiana for Astrophysics Houston, Texas Cambridge, Massachusetts Zhibin Dai Lee Anne M. Willson Yunnan Observatories Ulisse Munari Iowa State University Kunming City, Yunnan, China INAF/Astronomical Observatory Ames, Iowa of Padua Kosmas Gazeas Asiago, Italy University of Athens Athens, Greece The Council of the American Association of Variable Star Observers 2015–2016 Director Stella Kafka President Kristine Larsen Past President Jennifer L. Sokoloski 1st Vice President Roger S. Kolman 2nd Vice President Kevin B. Marvel Secretary Gary Walker Treasurer Bill Goff Councilors Joyce A. Guzik Aaron Price Barbara G. Harris Richard Sabo Katrien Kolenberg William Stein Joseph Patterson ISSN 0271-9053 (print) ISSN 2380-3606 (online) JAAVSO The Journal of The American Association of Variable Star Observers Volume 44 Number 1 2016 AAVSO 49 Bay State Road ISSN 0271-9053 (print) Cambridge, MA 02138 ISSN 2380-3606 (online) USA Publication Schedule The Journal of the American Association of Variable Star Observers is published twice a year, June 15 (Number 1 of the volume) and December 15 (Number 2 of the volume). The submission window for inclusion in the next issue of JAAVSO closes six weeks before the publication date. A manuscript will be added to the table of contents for an issue when it has been fully accepted for publication upon successful completion of the referee process; these articles will be available online prior to the publication date. An author may not specify in which issue of JAAVSO a manuscript is to be published; accepted manuscripts will be published in the next available issue, except under extraordinary circumstances. Page Charges Page charges are waived for Members of the AAVSO. Publication of unsolicited manuscripts in JAAVSO requires a page charge of US $100/page for the final printed manuscript. Page charge waivers may be provided under certain circumstances. Publication in JAAVSO With the exception of abstracts of papers presented at AAVSO meetings, papers submitted to JAAVSO are peer-reviewed by individuals knowledgable about the topic being discussed. We cannot guarantee that all submissions to JAAVSO will be published, but we encourage authors of all experience levels and in all fields related to variable star astronomy and the AAVSO to submit manuscripts. We especially encourage students and other mentees of researchers affiliated with the AAVSO to submit results of their completed research. Subscriptions Institutions and Libraries may subscribe to JAAVSO as part of the Complete Publications Package or as an individual subscription. Individuals may purchase printed copies of recent JAAVSO issues via Createspace. Paper copies of JAAVSO issues prior to volume 36 are available in limited quantities directly from AAVSO Headquarters; please contact the AAVSO for available issues. Instructions for Submissions The Journal of the AAVSO welcomes papers from all persons concerned with the study of variable stars and topics specifically related to variability. All manuscripts should be written in a style designed to provide clear expositions of the topic. Contributors are encouraged to submit digitized text in MS WORD, LATEX+POSTSCRIPT, or plain-text format. Manuscripts may be mailed electronically to [email protected] or submitted by postal mail to JAAVSO, 49 Bay State Road, Cambridge, MA 02138, USA. Manuscripts must be submitted according to the following guidelines, or they will be returned to the author for correction: Manuscripts must be: 1) original, unpublished material; 2) written in English; 3) accompanied by an abstract of no more than 100 words. 4) not more than 2,500–3,000 words in length (10–12 pages double-spaced). Figures for publication must: 1) be camera-ready or in a high-contrast, high-resolution, standard digitized image format; 2) have all coordinates labeled with division marks on all four sides; 3) be accompanied by a caption that clearly explains all symbols and significance, so that the reader can understand the figure without reference to the text. Maximum published figure space is 4.5” by 7”. When submitting original figures, be sure to allow for reduction in size by making all symbols, letters, and division marks sufficiently large. Photographs and halftone images will be considered for publication if they directly illustrate the text. Tables should be: 1) provided separate from the main body of the text; 2) numbered sequentially and referred to by Arabic number in the text, e.g., Table 1. References: 1) References should relate directly to the text. 2) References should be keyed into the text with the author’s last name and the year of publication, e.g., (Smith 1974; Jones 1974) or Smith (1974) and Jones (1974). 3) In the case of three or more joint authors, the text reference should be written as follows: (Smith et al. 1976). 4) All references must be listed at the end of the text in alphabetical order by the author’s last name and the year of publication, according to the following format: Brown, J., and Green, E. B. 1974, Astrophys. J., 200, 765. Thomas, K. 1982, Phys. Rep., 33, 96. 5) Abbreviations used in references should be based on recent issues of the Journal or the listing provided at the beginning of Astronomy and Astrophysics Abstracts (Springer-Verlag). Miscellaneous: 1) Equations should be written on a separate line and given a sequential Arabic number in parentheses near the right-hand margin. Equations should be referred to in the text as, e.g., equation (1). 2) Magnitude will be assumed to be visual unless otherwise specified. 3) Manuscripts may be submitted to referees for review without obligation of publication. Online Access Articles published in JAAVSO, and information for authors and referees may be found online at: https://www.aavso.org/apps/jaavso/ © 2016 The American Association of Variable Star Observers. All rights reserved. The Journal of the American Association of Variable Star Observers Volume 44, Number 1, 2016 Editorial The (Variable) Stars Belong to Everyone John R. Percy 1 Variable Star Research Appearance of Special UGSU-type Phenomenon in the Light Curve of UGZ White Dwarf Nova RX Andromedae András Timár 3 Analysis of the Petersen Diagram of Double Mode High Amplitude δ Scuti Stars Riccardo Furgoni 6 Period Analysis, Photometry, and Astrophysical Modelling of the Contact Eclipsing Binary BC Gruis David J. W. Moriarty 10 TU Comae Berenices : Blazhko RR Lyrae Star in a Potential Binary System Pierre de Ponthière, Franz-Josef (Josch) Hambsch, Kenneth Menzies, Richard Sabo 18 Times of Minima and New Ephemerides for Southern Hemisphere Eclipsing Binary Stars Observed in 2015 Hristo Pavlov, Anthony Mallama, Brian Loader, Stephen Kerr 26 A Photometric Study of the Eclipsing Binary Star V2790 Orionis Edward J. Michaels 30 Long-Term Radial Velocity Monitoring of the HeI 6678 Line of z Tauri Ernst Pollmann 37 Analysis of Pulsating Components in the Eclipsing Binary Systems LT Herculis, RZ Microscopii, LY Puppis, V632 Scorpii, and V638 Scorpii Margaret Streamer, Terry Bohlsen, Yenal Ogmen 39 Intermittent Multi-Color Photometry for V1017 Sagittarii Arlo U. Landolt 45 The Variable Star V Sculptoris Arlo U. Landolt 50 A Photometric Study of the Eclipsing Binary Star V958 Monocerotis Edward J. Michaels 53 Instruments, Methods, and Techniques Monitoring the Continuing Spectral Evolution of Nova Delphini 2013 (V339 Del) with Low Resolution Spectroscopy Howard D. Mooers, William S. Wiethoff, Alexander Evich 60 Observing Globular Cluster RR Lyrae Variables with the BYU West Mountain Observatory Elizabeth J. Jeffery, Michael D. Joner 62 Table of Contents continued on following pages Variable Star Data Recent Maxima of 74 Short Period Pulsating Stars Gerard Samolyk 66 Recent Minima of 193 Eclipsing Binary Stars Gerard Samolyk 69 Education and Outreach An Undergraduate Research Experience on Studying Variable Stars Ariel Amaral, John R. Percy 72 Book Review Solar Science: Exploring Sunspots, Seasons,
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