Photometry of the long period dwarf nova GY Hya |
| |
| Institution: | 1. Laboratório Nacional de Astrofísica, Rua Estados Unidos, 154, CEP 37504-364, Itajubá - MG, Brazil;2. Bronberg and Kleinkaroo Observatories, CBA Pretoria/Kleinkaroo, Sint Helena 1B, PO Box 281, Calitzdorp 6660, South Africa;1. Department of Physics, Sapienza, University of Rome, P.le A. Moro 2, Roma, Italy;2. Astronomy Department, Harvard University, 60 Garden St., Cambridge, MA 02138, USA;1. Nazih Zuhdi Transplant Institute, Integris Baptist, Oklahoma City, OK, United States;2. Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, United States;3. Department of Pulmonary and Critical Care Medicine, Beaumont Health and OWUB school of Medicine, Rochester, MI, United States;4. Department of Pulmonary and Critical Care, University of Cincinnati, Cincinnati, OH, United States;1. Institute of Pharmacognosy, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary;2. Interdisciplinary Centre for Natural Products, University of Szeged, Szeged, Hungary;3. Department of Chemical and Environmental Process Engineering, Budapest University of Technology and Economics, Budapest, Hungary;4. Mcule.com Ltd., Budapest, Hungary;5. Department of Pharmacodynamics and Biopharmacy, University of Szeged, Szeged, Hungary;1. Queen Mary University, London, United Kingdom;2. School of Medicine, Ulster University, Northern Ireland;3. Antrim Laboratory, Antrim Area Hospital, Northern Ireland;4. Personalised Medicine Centre, School of Medicine, Ulster University, Northern Ireland |
| |
| Abstract: | Although comparatively bright, the cataclysmic variable GY Hya has not attracted much attention in the past. As part of a project to better characterize such systems photometrically, we observed light curves in white light, each spanning several hours, at Bronberg Observatory, South Africa, in 2004 and 2005, and at the Observatório do Pico dos Dias, Brazil, in 2014 and 2016. These data permit to study orbital modulations and their variations from season to season. The orbital period, already known from spectroscopic observations of Peters and Thorstensen (2005), is confirmed through strong ellipsoidal variations of the mass donor star in the system and the presence of eclipses of both components. A refined period of 0.34723972 (6) days and revised ephemeries are derived. Seasonal changes in the average orbital light curve can qualitatively be explained by variations of the contribution of a hot spot to the system light together with changes of the disk radius. The amplitude of the ellipsoidal variations and the eclipse contact phases permit to put some constraints on the mass ratio, orbital inclination and the relative brightness of the primary and secondary components. There are some indications that the disk radius during quiescence, expressed in units of the component separation, is smaller than in other dwarf novae. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
