MN Dra - In-the-Gap Dwarf Nova With Negative Superhumps
Elena Pavlenko, Taichi Kato, Max Andreev, Alexandr Sklyanov, Alexandra Zubareva, Denis Samsonov, Irina Voloshina, Vladimir Metlov, Sergey Shugarov, Nikolay Para… 展开作者
Elena Pavlenko, Taichi Kato, Max Andreev, Alexandr Sklyanov, Alexandra Zubareva, Denis Samsonov, Irina Voloshina, Vladimir Metlov, Sergey Shugarov, Nikolay Parakhin, Alex Golovin, Oksana Antoniuk
备注：
17TH European White Dwarf Workshop. AIP Conference Proceedings, Volume 1273, pp. 320-323 (2010)
2009年8月至11月，对MN Dra进行了77个夜晚的多站测光观测。总暴露时间为433小时。在此期间，这颗双星经历了两次超级爆发和五次正常爆发。在第一次超爆发期间，类SU UMa矮新星的正超峰随着极大的$\dot P = -1.5 \times 1.0^{-4}$而减少，证实了MN Dra的已知行为[1]。在超级爆发之间，MN Dra显示出负的超级驼峰。它们的周期在0.096天的值附近周期性变化。
英文摘要：
The multi-site photometric observations of MN Dra were made over 77 nights in August-November, 2009. The total exposure was 433 hours. During this time the binary underwent two superoutbursts and five normal outbursts. During the course of first superoutburst period of positive superhumps decreased with extremely large $\dot P = -1.5 \times 1.0^{-4}$ for SU UMa-like dwarf novae, confirming known behavior of MN Dra [1]. Between the superoutbursts MN Dra displayed negative superhumps. Their period changed cyclically around 0.096-day value.
We have summarized the current understanding and recently obtained findings about WZ Sge-type dwarf novae. We also reviewed the historical development of the understanding of these objects, provided the modern criteria, and reviewed the past research in relation to superhumps, early superhumps and the outburst mechanism. We regard that the presence of early superhumps (reflecting the 2:1 resonance) and long or multiple rebrightenings are the best distinguishing properties of WZ Sge-type dwarf novae. We provided the updated list of nearly 100 WZ Sge-type dwarf novae mainly based on the data obt…
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Photometric Analysis of TCP J20171288$+$1156589 -- WZ Sge Type Dwarf Nova with Delayed Ordinary Superhumps Emergence
Institute of Astronomy of the Russian Academy of Sciences（俄罗斯科学院天体物理研究所）；Sternberg Astronomical Institute, Lomonosov Moscow State University（莫斯科国立大学列别捷夫天文研究所）；Astronomical Institute of the Slovak Academy of Sciences（斯洛伐克科学院天文研究所）；Crimean Astrophysical Observatory（克里米亚天体物理观测站）；Vereniging voor Sterrenkunde（比利时天文协会）
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A probable inside-out dwarf nova outburst from the period bouncer candidate ASASSN-25dc
South African Astronomical Observatory（南非天文台）；University of Cape Town（开普敦大学）；Okayama Observatory, Kyoto University（京都大学冈山天文台）；Kyoto University（京都大学）；Kanazawa University（金泽大学）；The University of Tokyo（东京大学）；University of the Free State（自由州大学）
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We report K2 observations of the eclipsing cataclysmic variable V729 Sgr which covered nearly 80 days in duration. We find five short outbursts and two long outbursts, one of which shows a clear plateau phase in the rise to maximum brightness. The mean time between successive short outbursts is ~10 d while the time between the two long outbursts is ~38 d. The frequency of these outbursts are unprecedented for a CV above the orbital period gap. We find evidence that the mid-point of the eclipse occurs systematically earlier in outburst than in quiescence. During five of the six quiescent epochs…
