@article {28457,
	title = {Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae},
	volume = {61},
	year = {2009},
	month = {2009/12/1},
	pages = {S395 - S616},
	abstract = {We systematically surveyed period variations of superhumps in SU UMa-type dwarf novae based on newly obtained data and past publications. In many systems, the evolution of the superhump period is found to be composed of three distinct stages: an early evolutionary stage with a longer superhump period, a middle stage with systematically varying periods, and a final stage with a shorter, stable superhump period. During the middle stage, many systems with superhump periods of less than 0.08 d show positive period derivatives. We present observational characteristics of these stages and give greatly improved statistics. Contrary to an earlier claim, we found no clear evidence for a variation of period derivatives among different superoutbursts of the same object. We present an interpretation that the lengthening of the superhump period is a result of the outward propagation of an eccentricity wave, which is limited by the radius near the tidal truncation. We interpret that late-stage superhumps are rejuvenated excitation of a 3:1 resonance when superhumps in the outer disk are effectively quenched. The general behavior of the period variation, particularly in systems with short orbital periods, appears to follow a scenario proposed in Kato, Maehara, and Monard (2008, PASJ, 60, L23). We also present an observational summary of WZ Sge-type dwarf novae. Many of them have shown long-enduring superhumps during a post-superoutburst stage having longer periods than those during the main superoutburst. The period derivatives in WZ Sge-type dwarf novae are found to be strongly correlated with the fractional superhump excess, or consequently with the mass ratio. WZ Sge-type dwarf novae with a long-lasting rebrightening or with multiple rebrightenings tend to have smaller period derivatives, and are excellent candidates for those systems around or after the period minimum of evolution of cataclysmic variables.},
	keywords = {Astrophysics - Solar and Stellar Astrophysics},
	isbn = {0004-6264},
	url = {https://ui.adsabs.harvard.edu/abs/2009PASJ...61S.395K},
	author = {Kato, Taichi and Imada, Akira and Uemura, Makoto and Nogami, Daisaku and Maehara, Hiroyuki and Ishioka, Ryoko and Baba, Hajime and Matsumoto, Katsura and Iwamatsu, Hidetoshi and Kubota, Kaori and Sugiyasu, Kei and Soejima, Yuichi and Moritani, Yuuki and Ohshima, Tomohito and Ohashi, Hiroyuki and Tanaka, Junpei and Sasada, Mahito and Arai, Akira and Nakajima, Kazuhiro and Kiyota, Seiichiro and Tanabe, Kenji and Imamura, Kazuyoshi and Kunitomi, Nanae and Kunihiro, Kenji and Taguchi, Hiroki and Koizumi, Mitsuo and Yamada, Norimi and Nishi, Yuichi and Kida, Mayumi and Tanaka, Sawa and Ueoka, Rie and Yasui, Hideki and Maruoka, Koichi and Henden, Arne and Oksanen, Arto and Moilanen, Marko and Tikkanen, Petri and Aho, Mika and Monard, Berto and Itoh, Hiroshi and Dubovsky, Pavol A. and Kudzej, Igor and Dancikova, Radka and Vanmunster, Tonny and Pietz, Jochen and Bolt, Greg and Boyd, David and Nelson, Peter and Krajci, Thomas and Cook, Lewis M. and Torii, Ken{\textquoteright}ichi and Starkey, Donn R. and Shears, Jeremy and Jensen, Lasse-Teist and Masi, Gianluca and Hynek, Tom{\'a}{\v s} and Nov{\'a}k, Rudolf and Koci{\'a}n, Radek and Kr{\'a}l, Luk{\'a}{\v s} and Ku{\v c}{\'a}kov{\'a}, Hana and Kolasa, Marek and {\v S}tastn{\'y}, Petr and Staels, Bart and Miller, Ian and Sano, Yasuo and Ponthi{\`e}re, Pierre de and Miyashita, Atsushi and Crawford, Tim and Brady, Steve and Santallo, Roland and Richards, Tom and Martin, Brian and Buczynski, Denis and Richmond, Michael and Kern, Jim and Davis, Stacey and Crabtree, Dustin and Beaulieu, Kevin and Davis, Tracy and Aggleton, Matt and Morelle, Etienne and Pavlenko, Elena P. and Andreev, Maksim and Baklanov, Alexander and Koppelman, Michael D. and Billings, Gary and Urban{\v c}ok, L{\textquoteright}ubom{\'\i}r and {\"O}gmen, Yenal and Heathcote, Bernard and Gomez, Tomas L. and Voloshina, Irina and Retter, Alon and Mularczyk, Krzysztof and Z{\l}oczewski, Kamil and Olech, Arkadiusz and Kedzierski, Piotr and Pickard, Roger D. and Stockdale, Chris and Virtanen, Jani and Morikawa, Koichi and Hambsch, Franz-Josef and Garradd, Gordon and Gualdoni, Carlo and Geary, Keith and Omodaka, Toshihiro and Sakai, Nobuyuki and Michel, Raul and C{\'a}rdenas, A. A. and Gazeas, Kosmas D. and Niarchos, Panos G. and Yushchenko, Alexander V. and Mallia, Franco and Fiaschi, Marco and Good, Gerry A. and Walker, Stan and James, Nick and Douzu, Ken-ichi and Julian, Wm Mack and Butterworth, Neil D. and Shugarov, Sergey Yu. and Volkov, Igor and Chochol, Drahomir and Katysheva, Natalia and Rosenbush, Alexander E. and Khramtsova, Maria and Kehusmaa, Petri and Reszelski, Maciej and Bedient, James and Liller, William and Pojma{\'n}ski, Grzegorz and Simonsen, Mike and Stubbings, Rod and Schmeer, Patrick and Muyllaert, Eddy and Kinnunen, Timo and Poyner, Gary and Ripero, Jose and Kriebel, Wolfgang}
}
