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Multi-Color Photometry of the Hot R Coronae Borealis Star, MV Sagittarii

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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. Williams Kunming City, Yunnan, China for Astrophysics Whitestown, Indiana Cambridge, Massachusetts The Council of the American Association of Variable Star Observers 2016–2017 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 Robert Stephens Councilors Richard Berry Katrien Kolenberg Tom Calderwood Richard S. Post Joyce A. Guzik Gregory R. Sivakoff Michael Joner William Stein ISSN 0271-9053 (print) ISSN 2380-3606 (online) JAAVSO The Journal of The American Association of Variable Star Observers Volume 45 Number 2 2017 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 JAAVSO 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/ © 2017 The American Association of Variable Star Observers. All rights reserved. The Journal of the American Association of Variable Star Observers Volume 45, Number 2, 2017 Editorial JAAVSO: Past, Present, and Future John R. Percy 131 Variable Star Research A Photometric Study of the Eclipsing Binary QT Ursae Majoris Edward J. Michaels 133 Observations and Analysis of the Extreme Mass Ratio, High Fill-out Solar Type Binary, V1695 Aquilae Ronald G. Samec, Christopher R. Gray, Daniel Caton, Danny R. Faulkner, Robert Hill, Walter Van Hamme 140 BVRI Photometric Study of High Mass Ratio, Detached, Pre-contact W UMa Binary GQ Cancri Ronald G. Samec, Amber Olson, Daniel Caton, Danny R. Faulkner 148 Multi-color Photometry of the Hot R Coronae Borealis Star, MV Sagittarii Arlo U. Landolt, James L. Clem 159 New Observations of AD Serpentis Samantha Raymond, Ximena Morales, Wayne Osborn 169 BVRcIc Study of the Short Period Solar Type, Near Contact Binary, NSVS 10083189 Ronald G. Samec, Amber Olsen, Daniel B. Caton, Danny R. Faulkner, Robert L. Hill , Walter Van Hamme 173 Evidence for High Eccentricity and Apsidal Motion in the Detached Eclipsing Binary GSC 04052-01378 Riccardo Furgoni, Gary Billings 186 Preliminary Modeling of the Eclipsing Binary Star GSC 05765-01271 Sara Marullo, Alessandro Marchini, Lorenzo Franco, Riccardo Papini, Fabio Salvaggio 193 Amplitude Variations in Pulsating Red Giants. II. Some Systematics John R. Percy, Jennifer Laing 197 Improving the Photometric Calibration of the Enigmatic Star KIC 8462852 Adam J. Lahey, Douglas M. Dimick, Andrew C. Layden 202 Variable Star Data Visual Times of Maxima for Short Period Pulsating Stars II Gerard Samolyk 209 Recent Minima of 196 Eclipsing Binary Stars Gerard Samolyk 215 Table of Contents continued on following pages New Variable Stars Discovered by Data Mining Images Taken during Recent Asteroid Photometric Observations. II. Results from July 2015 through December 2016 Riccardo Papini, Alessandro Marchini, Fabio Salvaggio, Davide Agnetti, Paolo Bacci, Massimo
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