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50 results on '"Masi, Gianluca"'

1. Metastatic Colorectal Cancer Outcomes by Age among ARCAD First- and Second-Line Clinical Trials

Author: MS Medische Oncologie, Cancer, McCleary, Nadine J., Harmsen, William S., Haakenstad, Ellana, Cleary, James M., Meyerhardt, Jeffrey A., Zalcberg, John, Adams, Richard, Grothey, Axel, Sobrero, Alberto F., Van Cutsem, Eric, Goldberg, Richard M., Peeters, Marc, Tabernero, Josep, Seymour, Matt, Saltz, Leonard B., Giantonio, Bruce J., Arnold, Dirk, Rothenberg, Mace L., Koopman, Miriam, Schmoll, Hans Joachim, Pitot, Henry C., Hoff, Paulo M., Tebbutt, Niall, Masi, Gianluca, Souglakos, John, Bokemeyer, Carsten, Heinemann, Volker, Yoshino, Takayuki, Chibaudel, Benoist, Degramont, Aimery, Shi, Qian, S Lichtman, Stuart M., MS Medische Oncologie, Cancer, McCleary, Nadine J., Harmsen, William S., Haakenstad, Ellana, Cleary, James M., Meyerhardt, Jeffrey A., Zalcberg, John, Adams, Richard, Grothey, Axel, Sobrero, Alberto F., Van Cutsem, Eric, Goldberg, Richard M., Peeters, Marc, Tabernero, Josep, Seymour, Matt, Saltz, Leonard B., Giantonio, Bruce J., Arnold, Dirk, Rothenberg, Mace L., Koopman, Miriam, Schmoll, Hans Joachim, Pitot, Henry C., Hoff, Paulo M., Tebbutt, Niall, Masi, Gianluca, Souglakos, John, Bokemeyer, Carsten, Heinemann, Volker, Yoshino, Takayuki, Chibaudel, Benoist, Degramont, Aimery, Shi, Qian, and S Lichtman, Stuart M.
Published: 2022

2. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. X: The Tenth Year (2017)

Author: Kato, Taichi, Isogai, Keisuke, Wakamatsu, Yasuyuki, Hambsch, Franz-Josef, Itoh, Hiroshi, Tordai, Tamas, Vanmunster, Tonny, Dubovsky, Pavol A., Kudzej, Igor, Medulka, Tomas, Kimura, Mariko, Ohnishi, Ryuhei, Monard, Berto, Pavlenko, Elena P., Antonyuk, Kirill A., Pit, Nikolaj V., Antonyuk, Oksana I., Babina, Julia V., Baklanov, Aleksei V., Sosnovskij, Aleksei A., Pickard, Roger D., Miller, Ian, Maeda, Yutaka, de Miguel, Enrique, Brincat, Stephen M., Licchelli, Domenico, Cook, Lewis M., Shugarov, Sergey Yu., Zaostrojnykh, Anna M., Chochol, Drahomir, Golysheva, Polina, Katysheva, Natalia, Zubareva, Alexandra M., Stone, Geoff, Kasai, Kiyoshi, Starr, Peter, Littlefield, Colin, Kiyota, Seiichiro, Andreev, Maksim V., Sergeev, Alexandr V., Ruiz, Javier, Myers, Gordon, Simon, Andrii O., Vasylenko, Volodymyr V., Soldan, Francisco, Ogmen, Yenal, Nakajima, Kazuhiro, Nelson, Peter, Masi, Gianluca, Menzies, Kenneth, Sabo, Richard, Bolt, Greg, Dvorak, Shawn, Stanek, Krzysztof Z., Shields, Joseph V., Kochanek, Christopher S., Holoien, Thomas W. -S., Shappee, Benjamin, Prieto, Jose L., Kojima, Tadashi, Nishimura, Hideo, Kaneko, Shizuo, Fujikawa, Shigehisa, Stubbings, Rod, Muyllaert, Eddy, Poyner, Gary, Moriyama, Masayuki, Maehara, Hiroyuki, Schmeer, Patrick, Denisenko, Denis, Kato, Taichi, Isogai, Keisuke, Wakamatsu, Yasuyuki, Hambsch, Franz-Josef, Itoh, Hiroshi, Tordai, Tamas, Vanmunster, Tonny, Dubovsky, Pavol A., Kudzej, Igor, Medulka, Tomas, Kimura, Mariko, Ohnishi, Ryuhei, Monard, Berto, Pavlenko, Elena P., Antonyuk, Kirill A., Pit, Nikolaj V., Antonyuk, Oksana I., Babina, Julia V., Baklanov, Aleksei V., Sosnovskij, Aleksei A., Pickard, Roger D., Miller, Ian, Maeda, Yutaka, de Miguel, Enrique, Brincat, Stephen M., Licchelli, Domenico, Cook, Lewis M., Shugarov, Sergey Yu., Zaostrojnykh, Anna M., Chochol, Drahomir, Golysheva, Polina, Katysheva, Natalia, Zubareva, Alexandra M., Stone, Geoff, Kasai, Kiyoshi, Starr, Peter, Littlefield, Colin, Kiyota, Seiichiro, Andreev, Maksim V., Sergeev, Alexandr V., Ruiz, Javier, Myers, Gordon, Simon, Andrii O., Vasylenko, Volodymyr V., Soldan, Francisco, Ogmen, Yenal, Nakajima, Kazuhiro, Nelson, Peter, Masi, Gianluca, Menzies, Kenneth, Sabo, Richard, Bolt, Greg, Dvorak, Shawn, Stanek, Krzysztof Z., Shields, Joseph V., Kochanek, Christopher S., Holoien, Thomas W. -S., Shappee, Benjamin, Prieto, Jose L., Kojima, Tadashi, Nishimura, Hideo, Kaneko, Shizuo, Fujikawa, Shigehisa, Stubbings, Rod, Muyllaert, Eddy, Poyner, Gary, Moriyama, Masayuki, Maehara, Hiroyuki, Schmeer, Patrick, and Denisenko, Denis
Abstract: Continuing the project described by Kato et al. (2009, PASJ, 61, S395, arXiv/0905.1757), we collected times of superhump maxima for 102 SU UMa-type dwarf novae observed mainly during the 2017 season and characterized these objects. WZ Sge-type stars identified in this study are PT And, ASASSN-17ei, ASASSN-17el, ASASSN-17es, ASASSN-17fn, ASASSN-17fz, ASASSN-17hw, ASASSN-17kd, ASASSN-17la, PNV J20205397+2508145 and TCP J00332502-3518565. We obtained new mass ratios for 7 objects using growing superhumps (stage A). ASASSN-17gf is an EI Psc-type object below the period minimum. CRTS J080941.3+171528 and DDE 51 are objects in the period gap and both showed long-lasting phase of stage A superhumps. We also summarized the recent advances in understanding of SU UMa-type and WZ Sge-type dwarf novae., Comment: The main text and Supporting information are combined in this arXiv version. Accepted for publication in PASJ, author list has been corrected. Follow-up to arXiv:1706.03870, arXiv:1605.06221, ... , arXiv:1009.5444, arXiv:0912.4321
Published: 2019
Full Text: View/download PDF

3. On the Electrical and Optical Features of the Plasma Coagulation Controller Low Temperature Atmospheric Plasma Jet

Author: Cordaro, L, De Masi, G, Fassina, A, Mancini, D, Cavazzana, R, Desideri, D, Sonato, P, Zuin, M, Zaniol, B, Martines, E, Cordaro, Luigi, De Masi, Gianluca, Fassina, Alessandro, Mancini, Davide, Cavazzana, Roberto, Desideri, Daniele, Sonato, Piergiorgio, Zuin, Matteo, Zaniol, Barbara, Martines, Emilio, Cordaro, L, De Masi, G, Fassina, A, Mancini, D, Cavazzana, R, Desideri, D, Sonato, P, Zuin, M, Zaniol, B, Martines, E, Cordaro, Luigi, De Masi, Gianluca, Fassina, Alessandro, Mancini, Davide, Cavazzana, Roberto, Desideri, Daniele, Sonato, Piergiorgio, Zuin, Matteo, Zaniol, Barbara, and Martines, Emilio
Abstract: We report on the electrical and optical characterization of the Plasma Coagulation Controller (PCC) device, a low temperature atmospheric plasma source for biomedical applications. This device, designed for the study of plasma-induced blood coagulation, has been developed to operate flexibly in several operational conditions, since it is possible to vary the applied voltage Vp and the pulse repetition rate f in a quite wide range ( Vp range: 2–12 kV, f range: 1–40 kHz). Emission spectroscopy measurements were conducted by varying the line of sight along the axis of helium and neon plasma plumes. The increase of the Reactive Oxygen and Nitrogen Species (RONS) has been observed, as one moves from inside the gas pipe to the outside, as a consequence of the gas mixture with the surrounding air. Furthermore, high-speed photographs of the plasma jet were taken, showing that the plasma is not uniformly distributed in a continuous volumetric region, the plasma being concentrated in localized structures called Pulsed Atmospheric-pressure Plasma Streams (PAPS). The propagation velocities of these objects have been examined, noting that they are not related to the propagation of ion sound waves. Rather, we provide indications that the streamer propagation speed is proportional to the electron drift velocity.
Published: 2019

4. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. X: The Tenth Year (2017)

Author: Kato, Taichi, Isogai, Keisuke, Wakamatsu, Yasuyuki, Hambsch, Franz-Josef, Itoh, Hiroshi, Tordai, Tamas, Vanmunster, Tonny, Dubovsky, Pavol A., Kudzej, Igor, Medulka, Tomas, Kimura, Mariko, Ohnishi, Ryuhei, Monard, Berto, Pavlenko, Elena P., Antonyuk, Kirill A., Pit, Nikolaj V., Antonyuk, Oksana I., Babina, Julia V., Baklanov, Aleksei V., Sosnovskij, Aleksei A., Pickard, Roger D., Miller, Ian, Maeda, Yutaka, de Miguel, Enrique, Brincat, Stephen M., Licchelli, Domenico, Cook, Lewis M., Shugarov, Sergey Yu., Zaostrojnykh, Anna M., Chochol, Drahomir, Golysheva, Polina, Katysheva, Natalia, Zubareva, Alexandra M., Stone, Geoff, Kasai, Kiyoshi, Starr, Peter, Littlefield, Colin, Kiyota, Seiichiro, Andreev, Maksim V., Sergeev, Alexandr V., Ruiz, Javier, Myers, Gordon, Simon, Andrii O., Vasylenko, Volodymyr V., Soldan, Francisco, Ogmen, Yenal, Nakajima, Kazuhiro, Nelson, Peter, Masi, Gianluca, Menzies, Kenneth, Sabo, Richard, Bolt, Greg, Dvorak, Shawn, Stanek, Krzysztof Z., Shields, Joseph V., Kochanek, Christopher S., Holoien, Thomas W. -S., Shappee, Benjamin, Prieto, Jose L., Kojima, Tadashi, Nishimura, Hideo, Kaneko, Shizuo, Fujikawa, Shigehisa, Stubbings, Rod, Muyllaert, Eddy, Poyner, Gary, Moriyama, Masayuki, Maehara, Hiroyuki, Schmeer, Patrick, Denisenko, Denis, Kato, Taichi, Isogai, Keisuke, Wakamatsu, Yasuyuki, Hambsch, Franz-Josef, Itoh, Hiroshi, Tordai, Tamas, Vanmunster, Tonny, Dubovsky, Pavol A., Kudzej, Igor, Medulka, Tomas, Kimura, Mariko, Ohnishi, Ryuhei, Monard, Berto, Pavlenko, Elena P., Antonyuk, Kirill A., Pit, Nikolaj V., Antonyuk, Oksana I., Babina, Julia V., Baklanov, Aleksei V., Sosnovskij, Aleksei A., Pickard, Roger D., Miller, Ian, Maeda, Yutaka, de Miguel, Enrique, Brincat, Stephen M., Licchelli, Domenico, Cook, Lewis M., Shugarov, Sergey Yu., Zaostrojnykh, Anna M., Chochol, Drahomir, Golysheva, Polina, Katysheva, Natalia, Zubareva, Alexandra M., Stone, Geoff, Kasai, Kiyoshi, Starr, Peter, Littlefield, Colin, Kiyota, Seiichiro, Andreev, Maksim V., Sergeev, Alexandr V., Ruiz, Javier, Myers, Gordon, Simon, Andrii O., Vasylenko, Volodymyr V., Soldan, Francisco, Ogmen, Yenal, Nakajima, Kazuhiro, Nelson, Peter, Masi, Gianluca, Menzies, Kenneth, Sabo, Richard, Bolt, Greg, Dvorak, Shawn, Stanek, Krzysztof Z., Shields, Joseph V., Kochanek, Christopher S., Holoien, Thomas W. -S., Shappee, Benjamin, Prieto, Jose L., Kojima, Tadashi, Nishimura, Hideo, Kaneko, Shizuo, Fujikawa, Shigehisa, Stubbings, Rod, Muyllaert, Eddy, Poyner, Gary, Moriyama, Masayuki, Maehara, Hiroyuki, Schmeer, Patrick, and Denisenko, Denis
Abstract: Continuing the project described by Kato et al. (2009, PASJ, 61, S395, arXiv/0905.1757), we collected times of superhump maxima for 102 SU UMa-type dwarf novae observed mainly during the 2017 season and characterized these objects. WZ Sge-type stars identified in this study are PT And, ASASSN-17ei, ASASSN-17el, ASASSN-17es, ASASSN-17fn, ASASSN-17fz, ASASSN-17hw, ASASSN-17kd, ASASSN-17la, PNV J20205397+2508145 and TCP J00332502-3518565. We obtained new mass ratios for 7 objects using growing superhumps (stage A). ASASSN-17gf is an EI Psc-type object below the period minimum. CRTS J080941.3+171528 and DDE 51 are objects in the period gap and both showed long-lasting phase of stage A superhumps. We also summarized the recent advances in understanding of SU UMa-type and WZ Sge-type dwarf novae., Comment: The main text and Supporting information are combined in this arXiv version. Accepted for publication in PASJ, author list has been corrected. Follow-up to arXiv:1706.03870, arXiv:1605.06221, ... , arXiv:1009.5444, arXiv:0912.4321
Published: 2019
Full Text: View/download PDF

5. On the Electrical and Optical Features of the Plasma Coagulation Controller Low Temperature Atmospheric Plasma Jet

Author: Cordaro, L, De Masi, G, Fassina, A, Mancini, D, Cavazzana, R, Desideri, D, Sonato, P, Zuin, M, Zaniol, B, Martines, E, Cordaro, Luigi, De Masi, Gianluca, Fassina, Alessandro, Mancini, Davide, Cavazzana, Roberto, Desideri, Daniele, Sonato, Piergiorgio, Zuin, Matteo, Zaniol, Barbara, Martines, Emilio, Cordaro, L, De Masi, G, Fassina, A, Mancini, D, Cavazzana, R, Desideri, D, Sonato, P, Zuin, M, Zaniol, B, Martines, E, Cordaro, Luigi, De Masi, Gianluca, Fassina, Alessandro, Mancini, Davide, Cavazzana, Roberto, Desideri, Daniele, Sonato, Piergiorgio, Zuin, Matteo, Zaniol, Barbara, and Martines, Emilio
Abstract: We report on the electrical and optical characterization of the Plasma Coagulation Controller (PCC) device, a low temperature atmospheric plasma source for biomedical applications. This device, designed for the study of plasma-induced blood coagulation, has been developed to operate flexibly in several operational conditions, since it is possible to vary the applied voltage (Formula presented.) and the pulse repetition rate f in a quite wide range ((Formula presented.) range: 2–12 kV, f range: 1–40 kHz). Emission spectroscopy measurements were conducted by varying the line of sight along the axis of helium and neon plasma plumes. The increase of the Reactive Oxygen and Nitrogen Species (RONS) has been observed, as one moves from inside the gas pipe to the outside, as a consequence of the gas mixture with the surrounding air. Furthermore, high-speed photographs of the plasma jet were taken, showing that the plasma is not uniformly distributed in a continuous volumetric region, the plasma being concentrated in localized structures called Pulsed Atmospheric-pressure Plasma Streams (PAPS). The propagation velocities of these objects have been examined, noting that they are not related to the propagation of ion sound waves. Rather, we provide indications that the streamer propagation speed is proportional to the electron drift velocity.
Published: 2019

6. Overview of the RFX-mod fusion science activity

Author: Zuin, M, DAL BELLO, S, Marrelli, L, Puiatti, M, Agostinetti, P, Agostini, M, Antoni, V, Auriemma, F, Barbisan, M, Barbui, T, Baruzzo, M, Belli, F, Bettini, P, Bigi, M, Bilel, R, Boldrin, M, Bolzonella, T, Bonfiglio, D, Brombin, M, Buffa, A, Bustreo, C, Canton, A, Cappello, S, Carraro, L, Cavazzana, R, Cester, D, Chacon, L, Chitarin, G, Cooper, W, Cordaro, L, DALLA PALMA, M, Deambrosis, S, Delogu, R, De Lorenzi, A, DE MASI, G, Dong, J, Escande, D, Fassina, A, Felici, F, Ferro, A, Finotti, C, Franz, P, Frassinetti, L, Gaio, E, Ghezzi, F, Giudicotti, L, Gnesotto, F, Gobbin, M, Gonzalez, W, Grando, L, Guo, S, Hanson, J, Hirshman, S, Innocente, P, Jackson, J, Kiyama, S, Komm, M, Kudlacek, O, Laguardia, A, Li, C, Liu, B, Liu, S, Liu, Y, López Bruna, D, Lorenzini, R, Luce, T, Luchetta, A, Maistrello, A, Manduchi, G, Mansfield, D, Marchiori, G, Marconato, N, Marcuzzi, D, Martin, P, Martines, E, Martini, S, Mazzitelli, G, Mccormack, O, Miorin, E, Momo, B, Moresco, M, Narushima, Y, Okabayashi, M, Paccagnella, R, Patel, N, Pavei, M, Peruzzo, S, Pilan, N, Pigatto, L, Piovan, R, Piovesan, P, Piron, C, Piron, L, Predebon, I, Pucella, G, Rea, C, Recchia, M, Rizzolo, A, Rostagni, G, Ruset, C, Sajò Bohus, L, Sakakita, H, Sanchez, R, Sarff, J, Sattin, F, Scarin, P, Schmitz, O, Schneider, W, Siragusa, M, Sonato, P, Spada, E, Spagnolo, S, Spolaore, M, Spong, D, Spizzo, G, Stevanato, L, Suzuki, Y, Taliercio, C, Terranova, D, Tudisco, O, Urso, G, Valente, M, Valisa, M, Vallar, M, Veranda, M, Vianello, N, Villone, F, Vincenzi, P, Visonà, N, White, R, Xanthopoulos, P, Xu, X, Yanovskiy, V, Zamengo, A, Zanca, P, Zaniol, B, Zanotto, L, Zhang, Y, Zilli, E, ZUIN, MATTEO, DAL BELLO, SILVIA, MARRELLI, LIONELLO, Puiatti, M. E., AGOSTINETTI, PIERO, AGOSTINI, MATTEO, ANTONI, VANNI, AURIEMMA, FULVIO, BARBISAN, MARCO, BARBUI, TULLIO, BARUZZO, MATTEO, Belli, F., BETTINI, PAOLO, Bigi, M., Bilel, R., Boldrin, M., BOLZONELLA, TOMMASO, BONFIGLIO, DANIELE, BROMBIN, MATTEO, BUFFA, ANTONIO, BUSTREO, CHIARA, CANTON, ALESSANDRA MARIA, CAPPELLO, SUSANNA, Carraro, L., Cavazzana, R., CESTER, DAVIDE, Chacon, L., CHITARIN, GIUSEPPE, Cooper, W. A., CORDARO, LUIGI, DALLA PALMA, MAURO, DEAMBROSIS, SILVIA MARIA, Delogu, R., De Lorenzi, A., DE MASI, GIANLUCA, Dong, J. Q., Escande, D. F., FASSINA, ALESSANDRO, Felici, F., Ferro, A., FINOTTI, CLAUDIO, Franz, P., FRASSINETTI, LORENZO, Gaio, E., GHEZZI, FEDERICO, GIUDICOTTI, LEONARDO, GNESOTTO, FRANCESCO, GOBBIN, MARCO, GONZALEZ, WINDER ALEXANDER, GRANDO, LUCA, Guo, S. C., Hanson, J. D., Hirshman, S. P., Innocente, P., Jackson, J. L., Kiyama, S., Komm, M., KUDLACEK, ONDREJ, LAGUARDIA, ANNA LUCIA, Li, C., Liu, B., Liu, S. F., Liu, Y. Q., López Bruna, D., Lorenzini, R., Luce, T. C., LUCHETTA, ADRIANO FRANCESCO, MAISTRELLO, ALBERTO, MANDUCHI, GABRIELE, Mansfield, D. K., Marchiori, G., MARCONATO, NICOLO', Marcuzzi, D., MARTIN, PIERO, MARTINES, EMILIO, MARTINI, STEFANO, Mazzitelli, G., Mccormack, O., Miorin, E., MOMO, BARBARA, MORESCO, MAURIZIO, Narushima, Y., Okabayashi, M., Paccagnella, R., Patel, N., Pavei, M., Peruzzo, S., Pilan, N., Pigatto, L., Piovan, R., Piovesan, P., Piron, C., Piron, L., Predebon, I., Pucella, G., Rea, C., Recchia, M., Rizzolo, A., Rostagni, G., Ruset, C., Sajò Bohus, L., Sakakita, H., Sanchez, R., Sarff, J. S., Sattin, F., Scarin, P., Schmitz, O., Schneider, W., Siragusa, M., Sonato, P., Spada, E., Spagnolo, S., Spolaore, M., Spong, D. A., Spizzo, G., Stevanato, L., Suzuki, Y., Taliercio, C., Terranova, D., Tudisco, O., Urso, G., Valente, M., Valisa, M., Vallar, M., Veranda, M., Vianello, N., Villone, F., Vincenzi, P., Visonà, N., White, R. B., Xanthopoulos, P., Xu, X. Y., Yanovskiy, V., Zamengo, A., Zanca, P., Zaniol, B., Zanotto, L., Zhang, Y., Zilli, E., Zuin, M, DAL BELLO, S, Marrelli, L, Puiatti, M, Agostinetti, P, Agostini, M, Antoni, V, Auriemma, F, Barbisan, M, Barbui, T, Baruzzo, M, Belli, F, Bettini, P, Bigi, M, Bilel, R, Boldrin, M, Bolzonella, T, Bonfiglio, D, Brombin, M, Buffa, A, Bustreo, C, Canton, A, Cappello, S, Carraro, L, Cavazzana, R, Cester, D, Chacon, L, Chitarin, G, Cooper, W, Cordaro, L, DALLA PALMA, M, Deambrosis, S, Delogu, R, De Lorenzi, A, DE MASI, G, Dong, J, Escande, D, Fassina, A, Felici, F, Ferro, A, Finotti, C, Franz, P, Frassinetti, L, Gaio, E, Ghezzi, F, Giudicotti, L, Gnesotto, F, Gobbin, M, Gonzalez, W, Grando, L, Guo, S, Hanson, J, Hirshman, S, Innocente, P, Jackson, J, Kiyama, S, Komm, M, Kudlacek, O, Laguardia, A, Li, C, Liu, B, Liu, S, Liu, Y, López Bruna, D, Lorenzini, R, Luce, T, Luchetta, A, Maistrello, A, Manduchi, G, Mansfield, D, Marchiori, G, Marconato, N, Marcuzzi, D, Martin, P, Martines, E, Martini, S, Mazzitelli, G, Mccormack, O, Miorin, E, Momo, B, Moresco, M, Narushima, Y, Okabayashi, M, Paccagnella, R, Patel, N, Pavei, M, Peruzzo, S, Pilan, N, Pigatto, L, Piovan, R, Piovesan, P, Piron, C, Piron, L, Predebon, I, Pucella, G, Rea, C, Recchia, M, Rizzolo, A, Rostagni, G, Ruset, C, Sajò Bohus, L, Sakakita, H, Sanchez, R, Sarff, J, Sattin, F, Scarin, P, Schmitz, O, Schneider, W, Siragusa, M, Sonato, P, Spada, E, Spagnolo, S, Spolaore, M, Spong, D, Spizzo, G, Stevanato, L, Suzuki, Y, Taliercio, C, Terranova, D, Tudisco, O, Urso, G, Valente, M, Valisa, M, Vallar, M, Veranda, M, Vianello, N, Villone, F, Vincenzi, P, Visonà, N, White, R, Xanthopoulos, P, Xu, X, Yanovskiy, V, Zamengo, A, Zanca, P, Zaniol, B, Zanotto, L, Zhang, Y, Zilli, E, ZUIN, MATTEO, DAL BELLO, SILVIA, MARRELLI, LIONELLO, Puiatti, M. E., AGOSTINETTI, PIERO, AGOSTINI, MATTEO, ANTONI, VANNI, AURIEMMA, FULVIO, BARBISAN, MARCO, BARBUI, TULLIO, BARUZZO, MATTEO, Belli, F., BETTINI, PAOLO, Bigi, M., Bilel, R., Boldrin, M., BOLZONELLA, TOMMASO, BONFIGLIO, DANIELE, BROMBIN, MATTEO, BUFFA, ANTONIO, BUSTREO, CHIARA, CANTON, ALESSANDRA MARIA, CAPPELLO, SUSANNA, Carraro, L., Cavazzana, R., CESTER, DAVIDE, Chacon, L., CHITARIN, GIUSEPPE, Cooper, W. A., CORDARO, LUIGI, DALLA PALMA, MAURO, DEAMBROSIS, SILVIA MARIA, Delogu, R., De Lorenzi, A., DE MASI, GIANLUCA, Dong, J. Q., Escande, D. F., FASSINA, ALESSANDRO, Felici, F., Ferro, A., FINOTTI, CLAUDIO, Franz, P., FRASSINETTI, LORENZO, Gaio, E., GHEZZI, FEDERICO, GIUDICOTTI, LEONARDO, GNESOTTO, FRANCESCO, GOBBIN, MARCO, GONZALEZ, WINDER ALEXANDER, GRANDO, LUCA, Guo, S. C., Hanson, J. D., Hirshman, S. P., Innocente, P., Jackson, J. L., Kiyama, S., Komm, M., KUDLACEK, ONDREJ, LAGUARDIA, ANNA LUCIA, Li, C., Liu, B., Liu, S. F., Liu, Y. Q., López Bruna, D., Lorenzini, R., Luce, T. C., LUCHETTA, ADRIANO FRANCESCO, MAISTRELLO, ALBERTO, MANDUCHI, GABRIELE, Mansfield, D. K., Marchiori, G., MARCONATO, NICOLO', Marcuzzi, D., MARTIN, PIERO, MARTINES, EMILIO, MARTINI, STEFANO, Mazzitelli, G., Mccormack, O., Miorin, E., MOMO, BARBARA, MORESCO, MAURIZIO, Narushima, Y., Okabayashi, M., Paccagnella, R., Patel, N., Pavei, M., Peruzzo, S., Pilan, N., Pigatto, L., Piovan, R., Piovesan, P., Piron, C., Piron, L., Predebon, I., Pucella, G., Rea, C., Recchia, M., Rizzolo, A., Rostagni, G., Ruset, C., Sajò Bohus, L., Sakakita, H., Sanchez, R., Sarff, J. S., Sattin, F., Scarin, P., Schmitz, O., Schneider, W., Siragusa, M., Sonato, P., Spada, E., Spagnolo, S., Spolaore, M., Spong, D. A., Spizzo, G., Stevanato, L., Suzuki, Y., Taliercio, C., Terranova, D., Tudisco, O., Urso, G., Valente, M., Valisa, M., Vallar, M., Veranda, M., Vianello, N., Villone, F., Vincenzi, P., Visonà, N., White, R. B., Xanthopoulos, P., Xu, X. Y., Yanovskiy, V., Zamengo, A., Zanca, P., Zaniol, B., Zanotto, L., Zhang, Y., and Zilli, E.
Abstract: This paper reports the main recent results of the RFX-mod fusion science activity. The RFX-mod device is characterized by a unique exibility in terms of accessible magnetic con gurations. Axisymmetric and helically shaped reversed- eld pinch equilibria have been studied, along with tokamak plasmas in a wide range of q(a) regimes (spanning from 4 down to 1.2 values). The full range of magnetic con gurations in between the two, the so-called ultra-low q ones, has been explored, with the aim of studying speci c physical issues common to all equilibria, such as, for example, the density limit phenomenon. The powerful RFX-mod feedback control system has been exploited for MHD control, which allowed us to extend the range of experimental parameters, as well as to induce speci c magnetic perturbations for the study of 3D effects. In particular, transport, edge and isotope effects in 3D equilibria have been investigated, along with runaway mitigations through induced magnetic perturbations. The rst transitions to an improved con nement scenario in circular and D-shaped tokamak plasmas have been obtained thanks to an active modi cation of the edge electric eld through a polarized electrode. The experiments are supported by intense modeling with 3D MHD, gyrokinetic, guiding center and transport codes. Proposed modi cations to the RFX-mod device, which will enable further contributions to the solution of key issues in the roadmap to ITER and DEMO, are also brie y presented.
Published: 2017

7. Superoutburst of WZSge-type dwarf nova below the period minimum: ASASSN-15po

Author: VEGA Agency (Slovakia), Ministry of Education, Culture, Sports, Science and Technology (Japan), Russian Foundation for Basic Research, Russian Science Foundation, Namekata, Kosuke, Isogai, Keisuke, Kato, Taichi, Littlefield, Colin, Matsumoto, Katsura, Kojiguchi, Naoto, Sugiura, Yuki, Uto, Yusuke, Fukushima, Daiki, Tatsumi, Taiki, Yamada, Eiji, Kamibetsunawa, Taku, Miguel, Enrique de, Stein, William L., Sabo, Richard, Andreev, Maksim V., Morelle, Etienne, Pavlenko, Elena P., Babina, Julia V., Baklanov, Alex V., Antonyuk, Kirill, Antonyuk, Oksana, Sosnovskij, Aleksei A., Shugarov, Sergey Yu., Golysheva, Polina Yu., Gladilina, Natalia G., Miller, Ian, Neustroev, Vitaly V., Chavushyan, Vahram, Valdés, José R., Sjoberg, George, Maeda, Yutaka, Itoh, Hiroshi, Masi, Gianluca, Michel, Raúl, Dubovsky, Pavol A., Kiyota, Seiichiro, Tordai, Tamás, Oksanen, Arto, Ruiz, Javier, Nogami, Daisaku, VEGA Agency (Slovakia), Ministry of Education, Culture, Sports, Science and Technology (Japan), Russian Foundation for Basic Research, Russian Science Foundation, Namekata, Kosuke, Isogai, Keisuke, Kato, Taichi, Littlefield, Colin, Matsumoto, Katsura, Kojiguchi, Naoto, Sugiura, Yuki, Uto, Yusuke, Fukushima, Daiki, Tatsumi, Taiki, Yamada, Eiji, Kamibetsunawa, Taku, Miguel, Enrique de, Stein, William L., Sabo, Richard, Andreev, Maksim V., Morelle, Etienne, Pavlenko, Elena P., Babina, Julia V., Baklanov, Alex V., Antonyuk, Kirill, Antonyuk, Oksana, Sosnovskij, Aleksei A., Shugarov, Sergey Yu., Golysheva, Polina Yu., Gladilina, Natalia G., Miller, Ian, Neustroev, Vitaly V., Chavushyan, Vahram, Valdés, José R., Sjoberg, George, Maeda, Yutaka, Itoh, Hiroshi, Masi, Gianluca, Michel, Raúl, Dubovsky, Pavol A., Kiyota, Seiichiro, Tordai, Tamás, Oksanen, Arto, Ruiz, Javier, and Nogami, Daisaku
Abstract: We report on a superoutburst of a WZ Sge-type dwarf nova (DN), ASASSN-15po. The light curve showed the main superoutburst and multiple rebrightenings. In this outburst, we observed early superhumps and growing (stage A) superhumps with periods of 0.050454(2) and 0.051809(13) d, respectively. We estimated that the mass ratio of secondary to primary (q) is 0.0699(8) by using P and a superhump period PSH of stage A. ASASSN-15po [P ∼ 72.6 min] is the first DN with an orbital period between 67-76 min. Although the theoretical predicted period minimum P of hydrogen-rich cataclysmic variables (CVs) is about 65-70 min, the observational cut-off of the orbital period distribution at 80 min implies that the period minimum is about 82min, and the value is widely accepted. We suggest the following four possibilities: the object is (1) a theoretical period minimum object, (2) a binary with a evolved secondary, (3) a binary with a metal-poor (Popullation II) seconday, or (4) a binary which was born with a brown-dwarf donor below the period minimum.
Published: 2017

8. The Post-SIR-Spheres Surgery Study (P4S): Retrospective Analysis of Safety Following Hepatic Resection or Transplantation in Patients Previously Treated with Selective Internal Radiation Therapy with Yttrium-90 Resin Microspheres

Author: Pardo, Fernando, Morris, David D.L., Iannitti, David, Chow, Pierce P.K., Stubbs, Richard, Gow, Paul John, Masi, Gianluca, Fisher, Kevin K.T., Lau, Wanyee W.Y., Kouladouros, Konstantinos, Katsanos, Georgios, Sangro, Bruno, Ercolani, Giorgio, Rotellar, Fernando, Bilbao, Josè Ignacio, Schoen, Michael, Lee, Rheun Chuan, Manas, Derek, Jeyarajah, Rohan, Donckier De Donceel, Vincent, Maleux, Geert, Pinna, Antonio Daniele, Bester, Lourens, Pardo, Fernando, Morris, David D.L., Iannitti, David, Chow, Pierce P.K., Stubbs, Richard, Gow, Paul John, Masi, Gianluca, Fisher, Kevin K.T., Lau, Wanyee W.Y., Kouladouros, Konstantinos, Katsanos, Georgios, Sangro, Bruno, Ercolani, Giorgio, Rotellar, Fernando, Bilbao, Josè Ignacio, Schoen, Michael, Lee, Rheun Chuan, Manas, Derek, Jeyarajah, Rohan, Donckier De Donceel, Vincent, Maleux, Geert, Pinna, Antonio Daniele, and Bester, Lourens
Abstract: Background: Reports show that selective internal radiation therapy (SIRT) may downsize inoperable liver tumors to resection or transplantation, or enable a bridge-to-transplant. A small-cohort study found that long-term survival in patients undergoing resection following SIRT appears possible but no robust studies on postsurgical safety outcomes exist. The Post-SIR-Spheres Surgery Study was an international, multicenter, retrospective study to assess safety outcomes of liver resection or transplantation following SIRT with yttrium-90 (Y-90) resin microspheres (SIR-Spheres®; Sirtex). Methods: Data were captured retrospectively at participating SIRT centers, with Y-90 resin microspheres, surgery (resection or transplantation), and follow-up for all eligible patients. Primary endpoints were perioperative and 90-day postoperative morbidity and mortality. Standard statistical methods were used. Results: The study included 100 patients [hepatocellular carcinoma: 49; metastatic colorectal cancer (mCRC): 30; cholangiocarcinoma, metastatic neuroendocrine tumor, other: 7 each]; 36% of patients had one or more lines of chemotherapy pre-SIRT. Sixty-three percent of patients had comorbidities, including hypertension (44%), diabetes (26%), and cardiopathy (16%). Post-SIRT, 71 patients were resected and 29 received a liver transplant. Grade 3+ peri/postoperative complications and any grade of liver failure were experienced by 24 and 7% of patients, respectively. Four patients died <90 days postsurgery; all were trisectionectomies (mCRC: 3; cholangiocarcinoma: 1) and typically had one or more previous chemotherapy lines and presurgical comorbidities. Conclusions: In 100 patients undergoing liver surgery after receiving SIRT, mortality and complication rates appeared acceptable given the risk profile of the recruited patients., SCOPUS: ar.j, info:eu-repo/semantics/published
Published: 2017

9. Superoutburst of WZ Sge-type Dwarf Nova Below the Period Minimum: ASASSN-15po

Author: Namekata, Kosuke, Isogai, Keisuke, Kato, Taichi, Littlefield, Colin, Matsumoto, Katsura, Kojiguchi, Naoto, Sugiura, Yuki, Uto, Yusuke, Fukushima, Daiki, Tatsumi, Taiki, Yamada, Eiji, Kamibetsunawa, Taku, de Miguel, Enrique, Stein, William L., Sabo, Richard, Andreev, Maksim V., Morelle, Etienne, Pavlenko, E. P., Babina, Julia V., Baklanov, Alex V., Antonyuk, Kirill A., Antonyuk, Okasana I., Sosnovskij, Aleksei A., Shugarov, Sergey Yu., Golysheva, Polina Yu., Gladilina, Natalia G., Miller, Ian, Neustroev, Vitaly V., Chavushyan, Vahram, Valdes, Jose R., Sjoberg, George, Maeda, Yutaka, Itoh, Hiroshi, Masi, Gianluca, Michel, Raul, Dubovsky, Pavol A., Kiyota, Seiichiro, Tordai, Tamas, Oksanen, Arto, Ruiz, Javier, Nogami, Daisaku, Namekata, Kosuke, Isogai, Keisuke, Kato, Taichi, Littlefield, Colin, Matsumoto, Katsura, Kojiguchi, Naoto, Sugiura, Yuki, Uto, Yusuke, Fukushima, Daiki, Tatsumi, Taiki, Yamada, Eiji, Kamibetsunawa, Taku, de Miguel, Enrique, Stein, William L., Sabo, Richard, Andreev, Maksim V., Morelle, Etienne, Pavlenko, E. P., Babina, Julia V., Baklanov, Alex V., Antonyuk, Kirill A., Antonyuk, Okasana I., Sosnovskij, Aleksei A., Shugarov, Sergey Yu., Golysheva, Polina Yu., Gladilina, Natalia G., Miller, Ian, Neustroev, Vitaly V., Chavushyan, Vahram, Valdes, Jose R., Sjoberg, George, Maeda, Yutaka, Itoh, Hiroshi, Masi, Gianluca, Michel, Raul, Dubovsky, Pavol A., Kiyota, Seiichiro, Tordai, Tamas, Oksanen, Arto, Ruiz, Javier, and Nogami, Daisaku
Abstract: We report on a superoutburst of a WZ Sge-type dwarf nova (DN), ASASSN-15po. The light curve showed the main superoutburst and multiple rebrightenings. In this outburst, we observed early superhumps and growing (stage A) superhumps with periods of 0.050454(2) and 0.051809(13) d, respectively. We estimated that the mass ratio of secondary to primary ($q$) is 0.0699(8) by using $P_{\rm orb}$ and a superhump period $P_{\rm SH}$ of stage A. ASASSN-15po [$P_{\rm orb} \sim$ 72.6 min] is the first DN with the orbital period between 67--76 min. Although the theoretical predicted period minimum $P_{\rm min}$ of hydrogen-rich cataclysmic variables (CVs) is about 65--70 min, the observational cut-off of the orbital period distribution at 80 min implies that the period minimum is about 82 min, and the value is widely accepted. We suggest the following four possibilities: the object is (1) a theoretical period minimum object (2) a binary with a evolved secondary (3) a binary with a metal-poor (Popullation II) seconday (4) a binary which was born with a brown-dwarf donor below the period minimum., Comment: 18 pages, 9 figures, accepted for publication in PASJ
Published: 2016
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10. Superoutburst of CR Bootis: Estimation of Mass Ratio of a typical AM CVn star by Stage A Superhumps

Author: Isogai, Keisuke, Kato, Taichi, Ohshima, Tomohito, Kasai, Kiyoshi, Oksanen, Arto, Masumoto, Kazunari, Fukushima, Daiki, Maeda, Kazuki, Kawabata, Miho, Matsuda, Risa, Kojiguchi, Naoto, Sugiura, Yuki, Takeda, Nao, Matsumoto, Katsura, Itoh, Hiroshi, Pavlenko, Elena P., Antonyuk, Kirill, Antonyuk, Oksana, Pit, Nikolai, Sosnovskij, Aleksei, Baklanov, Alex, Babina, Julia, Sklyanov, Aleksandr, Kiyota, Seiichiro, Hambsch, Franz-josef, Littlefield, Colin, Maeda, Yutaka, Cook, Lewis M., Masi, Gianluca, Dubovsky, Pavol A., Novak, Rudolf, Dvorak, Shawn, Imada, Akira, Nogami, Daisaku, Isogai, Keisuke, Kato, Taichi, Ohshima, Tomohito, Kasai, Kiyoshi, Oksanen, Arto, Masumoto, Kazunari, Fukushima, Daiki, Maeda, Kazuki, Kawabata, Miho, Matsuda, Risa, Kojiguchi, Naoto, Sugiura, Yuki, Takeda, Nao, Matsumoto, Katsura, Itoh, Hiroshi, Pavlenko, Elena P., Antonyuk, Kirill, Antonyuk, Oksana, Pit, Nikolai, Sosnovskij, Aleksei, Baklanov, Alex, Babina, Julia, Sklyanov, Aleksandr, Kiyota, Seiichiro, Hambsch, Franz-josef, Littlefield, Colin, Maeda, Yutaka, Cook, Lewis M., Masi, Gianluca, Dubovsky, Pavol A., Novak, Rudolf, Dvorak, Shawn, Imada, Akira, and Nogami, Daisaku
Abstract: We report on two superoutbursts of the AM CVn-type object CR Boo in 2014 April--March and 2015 May--June. A precursor outburst acompanied both of these superoutbursts. During the rising branch of the main superoutburst in 2014, we detected growing superhumps (stage A superhumps) whose period was $0.017669(24)$ d. Assuming that this period reflects the dynamical precession rate at the radius of the 3:1 resonance, we could estimate the mass ratio ($q=M_2/M_1$) of 0.101(4) by using the stage A superhump period and the orbital one of 0.0170290(6) d. This mass ratio is consistent with that expected by the theoretical evolutionary model of AM CVn-type objects. The detection of precursor outbursts and stage A superhumps is the second case in AM CVn-type objects. There are two interpretations of the outbursts of AM CVn-type objects. One is a dwarf nova (DN) outbursts analogy, which is caused by thermal and tidal instabilities. Another is the VY Scl-type variation, which is caused by the variation of the mass-transfer rate of the secondary. This detection of the superhump variations strongly suggests the former interpretation., Comment: 13 pages, 6 figures
Published: 2016
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11. Superoutburst of WZ Sge-type Dwarf Nova Below the Period Minimum: ASASSN-15po

Author: Namekata, Kosuke, Isogai, Keisuke, Kato, Taichi, Littlefield, Colin, Matsumoto, Katsura, Kojiguchi, Naoto, Sugiura, Yuki, Uto, Yusuke, Fukushima, Daiki, Tatsumi, Taiki, Yamada, Eiji, Kamibetsunawa, Taku, de Miguel, Enrique, Stein, William L., Sabo, Richard, Andreev, Maksim V., Morelle, Etienne, Pavlenko, E. P., Babina, Julia V., Baklanov, Alex V., Antonyuk, Kirill A., Antonyuk, Okasana I., Sosnovskij, Aleksei A., Shugarov, Sergey Yu., Golysheva, Polina Yu., Gladilina, Natalia G., Miller, Ian, Neustroev, Vitaly V., Chavushyan, Vahram, Valdes, Jose R., Sjoberg, George, Maeda, Yutaka, Itoh, Hiroshi, Masi, Gianluca, Michel, Raul, Dubovsky, Pavol A., Kiyota, Seiichiro, Tordai, Tamas, Oksanen, Arto, Ruiz, Javier, Nogami, Daisaku, Namekata, Kosuke, Isogai, Keisuke, Kato, Taichi, Littlefield, Colin, Matsumoto, Katsura, Kojiguchi, Naoto, Sugiura, Yuki, Uto, Yusuke, Fukushima, Daiki, Tatsumi, Taiki, Yamada, Eiji, Kamibetsunawa, Taku, de Miguel, Enrique, Stein, William L., Sabo, Richard, Andreev, Maksim V., Morelle, Etienne, Pavlenko, E. P., Babina, Julia V., Baklanov, Alex V., Antonyuk, Kirill A., Antonyuk, Okasana I., Sosnovskij, Aleksei A., Shugarov, Sergey Yu., Golysheva, Polina Yu., Gladilina, Natalia G., Miller, Ian, Neustroev, Vitaly V., Chavushyan, Vahram, Valdes, Jose R., Sjoberg, George, Maeda, Yutaka, Itoh, Hiroshi, Masi, Gianluca, Michel, Raul, Dubovsky, Pavol A., Kiyota, Seiichiro, Tordai, Tamas, Oksanen, Arto, Ruiz, Javier, and Nogami, Daisaku
Abstract: We report on a superoutburst of a WZ Sge-type dwarf nova (DN), ASASSN-15po. The light curve showed the main superoutburst and multiple rebrightenings. In this outburst, we observed early superhumps and growing (stage A) superhumps with periods of 0.050454(2) and 0.051809(13) d, respectively. We estimated that the mass ratio of secondary to primary ($q$) is 0.0699(8) by using $P_{\rm orb}$ and a superhump period $P_{\rm SH}$ of stage A. ASASSN-15po [$P_{\rm orb} \sim$ 72.6 min] is the first DN with the orbital period between 67--76 min. Although the theoretical predicted period minimum $P_{\rm min}$ of hydrogen-rich cataclysmic variables (CVs) is about 65--70 min, the observational cut-off of the orbital period distribution at 80 min implies that the period minimum is about 82 min, and the value is widely accepted. We suggest the following four possibilities: the object is (1) a theoretical period minimum object (2) a binary with a evolved secondary (3) a binary with a metal-poor (Popullation II) seconday (4) a binary which was born with a brown-dwarf donor below the period minimum., Comment: 18 pages, 9 figures, accepted for publication in PASJ
Published: 2016
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12. Superoutburst of CR Bootis: Estimation of Mass Ratio of a typical AM CVn star by Stage A Superhumps

Author: Isogai, Keisuke, Kato, Taichi, Ohshima, Tomohito, Kasai, Kiyoshi, Oksanen, Arto, Masumoto, Kazunari, Fukushima, Daiki, Maeda, Kazuki, Kawabata, Miho, Matsuda, Risa, Kojiguchi, Naoto, Sugiura, Yuki, Takeda, Nao, Matsumoto, Katsura, Itoh, Hiroshi, Pavlenko, Elena P., Antonyuk, Kirill, Antonyuk, Oksana, Pit, Nikolai, Sosnovskij, Aleksei, Baklanov, Alex, Babina, Julia, Sklyanov, Aleksandr, Kiyota, Seiichiro, Hambsch, Franz-josef, Littlefield, Colin, Maeda, Yutaka, Cook, Lewis M., Masi, Gianluca, Dubovsky, Pavol A., Novak, Rudolf, Dvorak, Shawn, Imada, Akira, Nogami, Daisaku, Isogai, Keisuke, Kato, Taichi, Ohshima, Tomohito, Kasai, Kiyoshi, Oksanen, Arto, Masumoto, Kazunari, Fukushima, Daiki, Maeda, Kazuki, Kawabata, Miho, Matsuda, Risa, Kojiguchi, Naoto, Sugiura, Yuki, Takeda, Nao, Matsumoto, Katsura, Itoh, Hiroshi, Pavlenko, Elena P., Antonyuk, Kirill, Antonyuk, Oksana, Pit, Nikolai, Sosnovskij, Aleksei, Baklanov, Alex, Babina, Julia, Sklyanov, Aleksandr, Kiyota, Seiichiro, Hambsch, Franz-josef, Littlefield, Colin, Maeda, Yutaka, Cook, Lewis M., Masi, Gianluca, Dubovsky, Pavol A., Novak, Rudolf, Dvorak, Shawn, Imada, Akira, and Nogami, Daisaku
Abstract: We report on two superoutbursts of the AM CVn-type object CR Boo in 2014 April--March and 2015 May--June. A precursor outburst acompanied both of these superoutbursts. During the rising branch of the main superoutburst in 2014, we detected growing superhumps (stage A superhumps) whose period was $0.017669(24)$ d. Assuming that this period reflects the dynamical precession rate at the radius of the 3:1 resonance, we could estimate the mass ratio ($q=M_2/M_1$) of 0.101(4) by using the stage A superhump period and the orbital one of 0.0170290(6) d. This mass ratio is consistent with that expected by the theoretical evolutionary model of AM CVn-type objects. The detection of precursor outbursts and stage A superhumps is the second case in AM CVn-type objects. There are two interpretations of the outbursts of AM CVn-type objects. One is a dwarf nova (DN) outbursts analogy, which is caused by thermal and tidal instabilities. Another is the VY Scl-type variation, which is caused by the variation of the mass-transfer rate of the secondary. This detection of the superhump variations strongly suggests the former interpretation., Comment: 13 pages, 6 figures
Published: 2016
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13. Timing of medical therapy and surgery in liver metastatic colorectal cancer

Author: Masi, Gianluca, Ferrero, Alessandro, Marino, Donatella, Masi, Gianluca, Ferrero, Alessandro, and Marino, Donatella
Abstract: No abstract available
Published: 2016

14. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. VII: The Seventh Year (2014-2015)

Author: Kato, Taichi, Hambsch, Franz-Josef, Dubovsky, Pavol A., Kudzej, Igor, Monard, Berto, Miller, Ian, Itoh, Hiroshi, Kiyota, Seiichiro, Masumoto, Kazunari, Fukushima, Daiki, Kinoshita, Hiroki, Maeda, Kazuki, Mikami, Jyunya, Matsuda, Risa, Kojiguchi, Naoto, Kawabata, Miho, Takenaka, Megumi, Matsumoto, Katsura, de Miguel, Enrique, Maeda, Yutaka, Ohshima, Tomohito, Isogai, Keisuke, Pickard, Roger D., Henden, Arne, Kafka, Stella, Akazawa, Hidehiko, Otani, Noritoshi, Ishibashi, Sakiko, Ogi, Minako, Tanabe, Kenji, Imamura, Kazuyoshi, Stein, William, Kasai, Kiyoshi, Vanmunster, Tonny, Starr, Peter, Pavlenko, Elena P., Antonyuk, Oksana I., Antonyuk, Kirill A., Sosnovskij, Aleksei A., Pit, Nikolaj V., Babina, Julia V., Sklyanov, Aleksandr, Novak, Rudolf, Oksanen, Arto, Dvorak, Shawn, Michel, Raul, Masi, Gianluca, Littlefield, Colin, Ulowetz, Joseph, Shugarov, Sergey Yu., Golysheva, Polina Yu., Chochol, Drahomir, Krushevska, Viktoriia, Ruiz, Javier, Tordai, Tamas, Morelle, Etienne, Sabo, Richard, Maehara, Hiroyuki, Richmond, Michael, Katysheva, Natalia, Hirosawa, Kenji, Goff, William N., Dubois, Franky, Logie, Ludwig, Rau, Steve, Voloshina, Irina B., Andreev, Maksim V., Shiokawa, Kazuhiko, Neustroev, Vitaly V., Sjoberg, George, Zharikov, Sergey, James, Nick, Bolt, Greg, Crawford, Tim, Buczynski, Denis, Cook, Lewis M., Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Denisenko, Denis, Nishimura, Hideo, Mukai, Masaru, Kaneko, Shizuo, Ueda, Seiji, Stubbings, Rod, Moriyama, Masayuki, Schmeer, Patrick, Muyllaert, Eddy, Shears, Jeremy, Modic, Robert J., Paxson, Kevin B., Kato, Taichi, Hambsch, Franz-Josef, Dubovsky, Pavol A., Kudzej, Igor, Monard, Berto, Miller, Ian, Itoh, Hiroshi, Kiyota, Seiichiro, Masumoto, Kazunari, Fukushima, Daiki, Kinoshita, Hiroki, Maeda, Kazuki, Mikami, Jyunya, Matsuda, Risa, Kojiguchi, Naoto, Kawabata, Miho, Takenaka, Megumi, Matsumoto, Katsura, de Miguel, Enrique, Maeda, Yutaka, Ohshima, Tomohito, Isogai, Keisuke, Pickard, Roger D., Henden, Arne, Kafka, Stella, Akazawa, Hidehiko, Otani, Noritoshi, Ishibashi, Sakiko, Ogi, Minako, Tanabe, Kenji, Imamura, Kazuyoshi, Stein, William, Kasai, Kiyoshi, Vanmunster, Tonny, Starr, Peter, Pavlenko, Elena P., Antonyuk, Oksana I., Antonyuk, Kirill A., Sosnovskij, Aleksei A., Pit, Nikolaj V., Babina, Julia V., Sklyanov, Aleksandr, Novak, Rudolf, Oksanen, Arto, Dvorak, Shawn, Michel, Raul, Masi, Gianluca, Littlefield, Colin, Ulowetz, Joseph, Shugarov, Sergey Yu., Golysheva, Polina Yu., Chochol, Drahomir, Krushevska, Viktoriia, Ruiz, Javier, Tordai, Tamas, Morelle, Etienne, Sabo, Richard, Maehara, Hiroyuki, Richmond, Michael, Katysheva, Natalia, Hirosawa, Kenji, Goff, William N., Dubois, Franky, Logie, Ludwig, Rau, Steve, Voloshina, Irina B., Andreev, Maksim V., Shiokawa, Kazuhiko, Neustroev, Vitaly V., Sjoberg, George, Zharikov, Sergey, James, Nick, Bolt, Greg, Crawford, Tim, Buczynski, Denis, Cook, Lewis M., Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Denisenko, Denis, Nishimura, Hideo, Mukai, Masaru, Kaneko, Shizuo, Ueda, Seiji, Stubbings, Rod, Moriyama, Masayuki, Schmeer, Patrick, Muyllaert, Eddy, Shears, Jeremy, Modic, Robert J., and Paxson, Kevin B.
Abstract: Continuing the project described by Kato et al. (2009, arXiv:0905.1757), we collected times of superhump maxima for 102 SU UMa-type dwarf novae observed mainly during the 2014-2015 season and characterized these objects. Our project has greatly improved the statistics of the distribution of orbital periods, which is a good approximation of the distribution of cataclysmic variables at the terminal evolutionary stage, and confirmed the presence of a period minimum at a period of 0.053 d and a period spike just above this period. The number density monotonically decreased toward the longer period and there was no strong indication of a period gap. We detected possible negative superhumps in Z Cha. It is possible that normal outbursts are also suppressed by the presence of a disk tilt in this system. There was no indication of enhanced orbital humps just preceding the superoutburst, and this result favors the thermal-tidal disk instability as the origin of superoutbursts. We detected superhumps in three AM CVn-type dwarf novae. Our observations and recent other detections suggest that 8% of objects showing dwarf nova-type outbursts are AM CVn-type objects. AM CVn-type objects and EI Psc-type object may be more abundant than previously recognized. OT J213806, a WZ Sge-type object, exhibited a remarkably different feature between the 2010 and 2014 superoutbursts. Although the 2014 superoutburst was much fainter the plateau phase was shorter than the 2010 one, the course of the rebrightening phase was similar. This object indicates that the O-C diagrams of superhumps can be indeed variable at least in WZ Sge-type objects. Four deeply eclipsing SU UMa-type dwarf novae (ASASSN-13cx, ASASSN-14ag, ASASSN-15bu, NSV 4618) were identified. We studied long-term trends in supercycles in MM Hya and CY UMa and found systematic variations of supercycles of ~20%., Comment: 116 pages, 151 figures, accepted for publication in PASJ
Published: 2015
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15. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. VII: The Seventh Year (2014-2015)

Author: Kato, Taichi, Hambsch, Franz-Josef, Dubovsky, Pavol A., Kudzej, Igor, Monard, Berto, Miller, Ian, Itoh, Hiroshi, Kiyota, Seiichiro, Masumoto, Kazunari, Fukushima, Daiki, Kinoshita, Hiroki, Maeda, Kazuki, Mikami, Jyunya, Matsuda, Risa, Kojiguchi, Naoto, Kawabata, Miho, Takenaka, Megumi, Matsumoto, Katsura, de Miguel, Enrique, Maeda, Yutaka, Ohshima, Tomohito, Isogai, Keisuke, Pickard, Roger D., Henden, Arne, Kafka, Stella, Akazawa, Hidehiko, Otani, Noritoshi, Ishibashi, Sakiko, Ogi, Minako, Tanabe, Kenji, Imamura, Kazuyoshi, Stein, William, Kasai, Kiyoshi, Vanmunster, Tonny, Starr, Peter, Pavlenko, Elena P., Antonyuk, Oksana I., Antonyuk, Kirill A., Sosnovskij, Aleksei A., Pit, Nikolaj V., Babina, Julia V., Sklyanov, Aleksandr, Novak, Rudolf, Oksanen, Arto, Dvorak, Shawn, Michel, Raul, Masi, Gianluca, Littlefield, Colin, Ulowetz, Joseph, Shugarov, Sergey Yu., Golysheva, Polina Yu., Chochol, Drahomir, Krushevska, Viktoriia, Ruiz, Javier, Tordai, Tamas, Morelle, Etienne, Sabo, Richard, Maehara, Hiroyuki, Richmond, Michael, Katysheva, Natalia, Hirosawa, Kenji, Goff, William N., Dubois, Franky, Logie, Ludwig, Rau, Steve, Voloshina, Irina B., Andreev, Maksim V., Shiokawa, Kazuhiko, Neustroev, Vitaly V., Sjoberg, George, Zharikov, Sergey, James, Nick, Bolt, Greg, Crawford, Tim, Buczynski, Denis, Cook, Lewis M., Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Denisenko, Denis, Nishimura, Hideo, Mukai, Masaru, Kaneko, Shizuo, Ueda, Seiji, Stubbings, Rod, Moriyama, Masayuki, Schmeer, Patrick, Muyllaert, Eddy, Shears, Jeremy, Modic, Robert J., Paxson, Kevin B., Kato, Taichi, Hambsch, Franz-Josef, Dubovsky, Pavol A., Kudzej, Igor, Monard, Berto, Miller, Ian, Itoh, Hiroshi, Kiyota, Seiichiro, Masumoto, Kazunari, Fukushima, Daiki, Kinoshita, Hiroki, Maeda, Kazuki, Mikami, Jyunya, Matsuda, Risa, Kojiguchi, Naoto, Kawabata, Miho, Takenaka, Megumi, Matsumoto, Katsura, de Miguel, Enrique, Maeda, Yutaka, Ohshima, Tomohito, Isogai, Keisuke, Pickard, Roger D., Henden, Arne, Kafka, Stella, Akazawa, Hidehiko, Otani, Noritoshi, Ishibashi, Sakiko, Ogi, Minako, Tanabe, Kenji, Imamura, Kazuyoshi, Stein, William, Kasai, Kiyoshi, Vanmunster, Tonny, Starr, Peter, Pavlenko, Elena P., Antonyuk, Oksana I., Antonyuk, Kirill A., Sosnovskij, Aleksei A., Pit, Nikolaj V., Babina, Julia V., Sklyanov, Aleksandr, Novak, Rudolf, Oksanen, Arto, Dvorak, Shawn, Michel, Raul, Masi, Gianluca, Littlefield, Colin, Ulowetz, Joseph, Shugarov, Sergey Yu., Golysheva, Polina Yu., Chochol, Drahomir, Krushevska, Viktoriia, Ruiz, Javier, Tordai, Tamas, Morelle, Etienne, Sabo, Richard, Maehara, Hiroyuki, Richmond, Michael, Katysheva, Natalia, Hirosawa, Kenji, Goff, William N., Dubois, Franky, Logie, Ludwig, Rau, Steve, Voloshina, Irina B., Andreev, Maksim V., Shiokawa, Kazuhiko, Neustroev, Vitaly V., Sjoberg, George, Zharikov, Sergey, James, Nick, Bolt, Greg, Crawford, Tim, Buczynski, Denis, Cook, Lewis M., Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Denisenko, Denis, Nishimura, Hideo, Mukai, Masaru, Kaneko, Shizuo, Ueda, Seiji, Stubbings, Rod, Moriyama, Masayuki, Schmeer, Patrick, Muyllaert, Eddy, Shears, Jeremy, Modic, Robert J., and Paxson, Kevin B.
Abstract: Continuing the project described by Kato et al. (2009, arXiv:0905.1757), we collected times of superhump maxima for 102 SU UMa-type dwarf novae observed mainly during the 2014-2015 season and characterized these objects. Our project has greatly improved the statistics of the distribution of orbital periods, which is a good approximation of the distribution of cataclysmic variables at the terminal evolutionary stage, and confirmed the presence of a period minimum at a period of 0.053 d and a period spike just above this period. The number density monotonically decreased toward the longer period and there was no strong indication of a period gap. We detected possible negative superhumps in Z Cha. It is possible that normal outbursts are also suppressed by the presence of a disk tilt in this system. There was no indication of enhanced orbital humps just preceding the superoutburst, and this result favors the thermal-tidal disk instability as the origin of superoutbursts. We detected superhumps in three AM CVn-type dwarf novae. Our observations and recent other detections suggest that 8% of objects showing dwarf nova-type outbursts are AM CVn-type objects. AM CVn-type objects and EI Psc-type object may be more abundant than previously recognized. OT J213806, a WZ Sge-type object, exhibited a remarkably different feature between the 2010 and 2014 superoutbursts. Although the 2014 superoutburst was much fainter the plateau phase was shorter than the 2010 one, the course of the rebrightening phase was similar. This object indicates that the O-C diagrams of superhumps can be indeed variable at least in WZ Sge-type objects. Four deeply eclipsing SU UMa-type dwarf novae (ASASSN-13cx, ASASSN-14ag, ASASSN-15bu, NSV 4618) were identified. We studied long-term trends in supercycles in MM Hya and CY UMa and found systematic variations of supercycles of ~20%., Comment: 116 pages, 151 figures, accepted for publication in PASJ
Published: 2015
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16. NY Serpentis: SU UMa-Type Nova in the Period Gap with Diversity of Normal Outbursts

Author: Pavlenko, Elena P., Kato, Taichi, Antonyuk, Oksana I., Ohshima, Tomohito, Hambsch, Franz-Josef, Antonyuk, Kirill A., Sosnovskij, Aleksei A., Baklanov, Alex V., Shugarov, Sergey Yu., Pit, Nikolaj V., Nakata, Chikako, Masi, Gianluca, Nakajima, Kazuhiro, Maehara, Hiroyuki, Dubovsky, Pavol A., Kudzej, Igor, Andreev, Maksim V., Kuznyetsova, Yuliana G., Vasiliskov, Kirill A., Pavlenko, Elena P., Kato, Taichi, Antonyuk, Oksana I., Ohshima, Tomohito, Hambsch, Franz-Josef, Antonyuk, Kirill A., Sosnovskij, Aleksei A., Baklanov, Alex V., Shugarov, Sergey Yu., Pit, Nikolaj V., Nakata, Chikako, Masi, Gianluca, Nakajima, Kazuhiro, Maehara, Hiroyuki, Dubovsky, Pavol A., Kudzej, Igor, Andreev, Maksim V., Kuznyetsova, Yuliana G., and Vasiliskov, Kirill A.
Abstract: We present photometric study of NY Ser, an in-the-gap SU UMa-type nova, in 2002 and 2013. We determined the duration of the superoutburst and the mean superhump period to be 18 d and 0.10458 d, respectively. We detected in 2013 that NY Ser showed two distinct states separated by the superoutburst. A state of rather infrequent normal outbursts lasted at least 44 d before the superoutburst and a state of frequent outbursts started immediately after the superoutburst and lasted at least for 34 d. Unlike a typical SU UMa star with bimodal distribution of the outbursts duration, NY Ser displayed a diversity of normal outbursts. In the state of infrequent outbursts, we detected a wide ~12 d outburst accompanied by 0.098 d orbital modulation but without superhumps ever established in NY Ser. We classified this as the "wide normal outburst". The orbital period dominated both in quiescence and during normal outbursts in this state. In the state of the most frequent normal outbursts, the 0.10465 d positive superhumps dominated and co-existed with the orbital modulation. In 2002 we detected the normal outburst of "intermediate" 5-6 d duration that was also accompanied by orbital modulations., Comment: 26 pages, 16 figures, accepted in PASJ
Published: 2014
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17. Superoutburst of SDSS J090221.35+381941.9: First Measurement of Mass Ratio in an AM CVn-Type Object using Growing Superhumps

Author: Kato, Taichi, Ohshima, Tomohito, Denisenko, Denis, Dubovsky, Pavol A., Kudzej, Igor, Stein, William, de Miguel, Enrique, Henden, Arne, Miller, Ian, Antonyuk, Kirill, Antonyuk, Oksana, Pit, Nikolaj, Sosnovskij, Aleksei, Baklanov, Alex, Babina, Julia, Pavlenko, Elena P., Matsumoto, Kazunari, Fukushima, Daiki, Takenaka, Megumi, Kawabata, Miho, Daisuke, Daisuke, Maeda, Kazuki, Matsuda, Risa, Matsumoto, Katsura, Littlefield, Colin, Oksanen, Arto, Itoh, Hiroshi, Masi, Gianluca, Nocentini, Francesca, Schmeer, Patrick, Pickard, Roger D., Kiyota, Seiichiro, Dvorak, Shawn, Ulowetz, Joseph, Maeda, Yutaka, Michel, Raul, Shugarov, Sergey Yu., Chochol, Drahomir, Novak, Rudolf, Kato, Taichi, Ohshima, Tomohito, Denisenko, Denis, Dubovsky, Pavol A., Kudzej, Igor, Stein, William, de Miguel, Enrique, Henden, Arne, Miller, Ian, Antonyuk, Kirill, Antonyuk, Oksana, Pit, Nikolaj, Sosnovskij, Aleksei, Baklanov, Alex, Babina, Julia, Pavlenko, Elena P., Matsumoto, Kazunari, Fukushima, Daiki, Takenaka, Megumi, Kawabata, Miho, Daisuke, Daisuke, Maeda, Kazuki, Matsuda, Risa, Matsumoto, Katsura, Littlefield, Colin, Oksanen, Arto, Itoh, Hiroshi, Masi, Gianluca, Nocentini, Francesca, Schmeer, Patrick, Pickard, Roger D., Kiyota, Seiichiro, Dvorak, Shawn, Ulowetz, Joseph, Maeda, Yutaka, Michel, Raul, Shugarov, Sergey Yu., Chochol, Drahomir, and Novak, Rudolf
Abstract: We report on a superoutburst of the AM CVn-type object SDSS J090221.35+381941.9 [J0902; orbital period 0.03355(6) d] in 2014 March-April. The entire outburst consisted of a precursor outburst and the main superoutburst, followed by a short rebrightening. During the rising branch of the main superoutburst, we detected growing superhumps (stage A superhumps) with a period of 0.03409(1) d. During the plateau phase of the superoutburst, superhumps with a shorter period (stage B superhumps) were observed. Using the orbital period and the period of the stage A superhumps, we were able to measure the dynamical precession rate of the accretion disk at the 3:1 resonance, and obtained a mass ratio (q) of 0.041(7). This is the first successful measurement of the mass ratio in an AM CVn-type object using the recently developed stage A superhump method. The value is generally in good agreement with the theoretical evolutionary model. The orbital period of J0902 is the longest among the outbursting AM CVn-type objects, and the borderline between the outbursting systems and systems with stable cool disks appears to be longer than had been supposed., Comment: 6 pages, 4 figures, accepted for publication in PASJ
Published: 2014
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18. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. VI: The Sixth Year (2013-2014)

Author: Kato, Taichi, Dubovsky, Pavol A., Kudzej, Igor, Hambsch, Franz-Josef, Miller, Ian, Ohshima, Tomohito, Nakata, Chikako, Kawabata, Miho, Nishino, Hirochika, Masumoto, Kazunari, Mizoguchi, Sahori, Yamanaka, Masayuki, Matsumoto, Katsura, Sakai, Daisuke, Fukushima, Daiki, Matsuura, Minami, Bouno, Genki, Takenaka, Megumi, Nakagawa, Shinichi, Noguchi, Ryo, Iino, Eriko, Pickard, Roger D., Maeda, Yutaka, Henden, Arne, Kasai, Kiyoshi, Kiyota, Seiichiro, Akazawa, Hidehiko, Imamura, Kazuyoshi, de Miguel, Enrique, Maehara, Hiroyuki, Monard, Berto, Pavlenko, Elena P., Antonyuk, Kirill, Pit, Nikolaj, Antonyuk, Oksana I., Baklanov, Aleksei V., Ruiz, Javier, Richmond, Michael, Oksanen, Arto, Harlingten, Caisey, Shugarov, Sergey Yu., Chochol, Drahomir, Masi, Gianluca, Nocentini, Francesca, Schmeer, Patrick, Bolt, Greg, Nelson, Peter, Ulowetz, Joseph, Sabo, Richard, Goff, William N., Stein, William, Michel, Raul, Dvorak, Shawn, Voloshina, Irina B., Metlov, Vladimir, Katysheva, Natalia, Neustroev, Vitaly V., Sjoberg, George, Littlefield, Colin, Debski, Bartlomiej, Sowicka, Paulina, Klimaszewski, Marcin, Curylo, Malgorzata, Morelle, Etienne, Curtis, Ivan A., Iwamatsu, Hidetoshi, Butterworth, Neil D., Andreev, Maksim V., Parakhin, Nikolai, Sklyanov, Aleksandr, Shiokawa, Kazuhiko, Novak, Rudolf, Irsmambetova, Tat'yana R., Itoh, Hiroshi, Ito, Yoshiharu, Hirosawa, Kenji, Denisenko, Denis, Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Itagaki, Koh-ichi, Stubbings, Rod, Ripero, Jose, Muyllaert, Eddy, Poyner, Gary, Kato, Taichi, Dubovsky, Pavol A., Kudzej, Igor, Hambsch, Franz-Josef, Miller, Ian, Ohshima, Tomohito, Nakata, Chikako, Kawabata, Miho, Nishino, Hirochika, Masumoto, Kazunari, Mizoguchi, Sahori, Yamanaka, Masayuki, Matsumoto, Katsura, Sakai, Daisuke, Fukushima, Daiki, Matsuura, Minami, Bouno, Genki, Takenaka, Megumi, Nakagawa, Shinichi, Noguchi, Ryo, Iino, Eriko, Pickard, Roger D., Maeda, Yutaka, Henden, Arne, Kasai, Kiyoshi, Kiyota, Seiichiro, Akazawa, Hidehiko, Imamura, Kazuyoshi, de Miguel, Enrique, Maehara, Hiroyuki, Monard, Berto, Pavlenko, Elena P., Antonyuk, Kirill, Pit, Nikolaj, Antonyuk, Oksana I., Baklanov, Aleksei V., Ruiz, Javier, Richmond, Michael, Oksanen, Arto, Harlingten, Caisey, Shugarov, Sergey Yu., Chochol, Drahomir, Masi, Gianluca, Nocentini, Francesca, Schmeer, Patrick, Bolt, Greg, Nelson, Peter, Ulowetz, Joseph, Sabo, Richard, Goff, William N., Stein, William, Michel, Raul, Dvorak, Shawn, Voloshina, Irina B., Metlov, Vladimir, Katysheva, Natalia, Neustroev, Vitaly V., Sjoberg, George, Littlefield, Colin, Debski, Bartlomiej, Sowicka, Paulina, Klimaszewski, Marcin, Curylo, Malgorzata, Morelle, Etienne, Curtis, Ivan A., Iwamatsu, Hidetoshi, Butterworth, Neil D., Andreev, Maksim V., Parakhin, Nikolai, Sklyanov, Aleksandr, Shiokawa, Kazuhiko, Novak, Rudolf, Irsmambetova, Tat'yana R., Itoh, Hiroshi, Ito, Yoshiharu, Hirosawa, Kenji, Denisenko, Denis, Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Itagaki, Koh-ichi, Stubbings, Rod, Ripero, Jose, Muyllaert, Eddy, and Poyner, Gary
Abstract: Continuing the project described by Kato et al. (2009, PASJ, 61, S395, arXiv:0905.1757), we collected times of superhump maxima for 56 SU UMa-type dwarf novae mainly observed during the 2013-2014 season and characterized these objects. We detected negative superhumps in VW Hyi and indicated that the low number of normal outbursts in some supercycle can be interpreted as a result of the disk tilt. This finding, combined with the Kepler observation of V1504 Cyg and V344 Lyr, suggests that the disk tilt is responsible for modulating the outburst pattern in SU UMa-type dwarf novae. We also studied the deeply eclipsing WZ Sge-type dwarf nova MASTER OT J005740.99+443101.5 and found evidence of a sharp eclipse during the phase of early superhumps. The profile can be reproduced by a combination of the eclipse of the axisymmetric disk and the uneclipsed light source of early superhumps. This finding confirms the lack of evince of a greatly enhanced hot spot during the early stage of WZ Sge-type outburst. We detected growing (stage A) superhumps in MN Dra and give a suggestion that some of SU UMa-type dwarf novae situated near the critical condition of tidal instability may show long-lasting stage A superhumps. The large negative period derivatives reported in such systems can be understood a result of the combination of stage A and B superhumps. The WZ Sge-type dwarf novae AL Com and ASASSN-13ck showed a long-lasting (plateau-type) rebrightening. In the early phase of the rebrightening, both objects showed a precursor-like outburst, suggesting that the long-lasting rebrightening is triggered by a precursor outburst., Comment: 73 pages, 88 figures, accepted for publication in PASJ
Published: 2014
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19. NY Serpentis: SU UMa-Type Nova in the Period Gap with Diversity of Normal Outbursts

Author: Pavlenko, Elena P., Kato, Taichi, Antonyuk, Oksana I., Ohshima, Tomohito, Hambsch, Franz-Josef, Antonyuk, Kirill A., Sosnovskij, Aleksei A., Baklanov, Alex V., Shugarov, Sergey Yu., Pit, Nikolaj V., Nakata, Chikako, Masi, Gianluca, Nakajima, Kazuhiro, Maehara, Hiroyuki, Dubovsky, Pavol A., Kudzej, Igor, Andreev, Maksim V., Kuznyetsova, Yuliana G., Vasiliskov, Kirill A., Pavlenko, Elena P., Kato, Taichi, Antonyuk, Oksana I., Ohshima, Tomohito, Hambsch, Franz-Josef, Antonyuk, Kirill A., Sosnovskij, Aleksei A., Baklanov, Alex V., Shugarov, Sergey Yu., Pit, Nikolaj V., Nakata, Chikako, Masi, Gianluca, Nakajima, Kazuhiro, Maehara, Hiroyuki, Dubovsky, Pavol A., Kudzej, Igor, Andreev, Maksim V., Kuznyetsova, Yuliana G., and Vasiliskov, Kirill A.
Abstract: We present photometric study of NY Ser, an in-the-gap SU UMa-type nova, in 2002 and 2013. We determined the duration of the superoutburst and the mean superhump period to be 18 d and 0.10458 d, respectively. We detected in 2013 that NY Ser showed two distinct states separated by the superoutburst. A state of rather infrequent normal outbursts lasted at least 44 d before the superoutburst and a state of frequent outbursts started immediately after the superoutburst and lasted at least for 34 d. Unlike a typical SU UMa star with bimodal distribution of the outbursts duration, NY Ser displayed a diversity of normal outbursts. In the state of infrequent outbursts, we detected a wide ~12 d outburst accompanied by 0.098 d orbital modulation but without superhumps ever established in NY Ser. We classified this as the "wide normal outburst". The orbital period dominated both in quiescence and during normal outbursts in this state. In the state of the most frequent normal outbursts, the 0.10465 d positive superhumps dominated and co-existed with the orbital modulation. In 2002 we detected the normal outburst of "intermediate" 5-6 d duration that was also accompanied by orbital modulations., Comment: 26 pages, 16 figures, accepted in PASJ
Published: 2014
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20. Superoutburst of SDSS J090221.35+381941.9: First Measurement of Mass Ratio in an AM CVn-Type Object using Growing Superhumps

Author: Kato, Taichi, Ohshima, Tomohito, Denisenko, Denis, Dubovsky, Pavol A., Kudzej, Igor, Stein, William, de Miguel, Enrique, Henden, Arne, Miller, Ian, Antonyuk, Kirill, Antonyuk, Oksana, Pit, Nikolaj, Sosnovskij, Aleksei, Baklanov, Alex, Babina, Julia, Pavlenko, Elena P., Matsumoto, Kazunari, Fukushima, Daiki, Takenaka, Megumi, Kawabata, Miho, Daisuke, Daisuke, Maeda, Kazuki, Matsuda, Risa, Matsumoto, Katsura, Littlefield, Colin, Oksanen, Arto, Itoh, Hiroshi, Masi, Gianluca, Nocentini, Francesca, Schmeer, Patrick, Pickard, Roger D., Kiyota, Seiichiro, Dvorak, Shawn, Ulowetz, Joseph, Maeda, Yutaka, Michel, Raul, Shugarov, Sergey Yu., Chochol, Drahomir, Novak, Rudolf, Kato, Taichi, Ohshima, Tomohito, Denisenko, Denis, Dubovsky, Pavol A., Kudzej, Igor, Stein, William, de Miguel, Enrique, Henden, Arne, Miller, Ian, Antonyuk, Kirill, Antonyuk, Oksana, Pit, Nikolaj, Sosnovskij, Aleksei, Baklanov, Alex, Babina, Julia, Pavlenko, Elena P., Matsumoto, Kazunari, Fukushima, Daiki, Takenaka, Megumi, Kawabata, Miho, Daisuke, Daisuke, Maeda, Kazuki, Matsuda, Risa, Matsumoto, Katsura, Littlefield, Colin, Oksanen, Arto, Itoh, Hiroshi, Masi, Gianluca, Nocentini, Francesca, Schmeer, Patrick, Pickard, Roger D., Kiyota, Seiichiro, Dvorak, Shawn, Ulowetz, Joseph, Maeda, Yutaka, Michel, Raul, Shugarov, Sergey Yu., Chochol, Drahomir, and Novak, Rudolf
Abstract: We report on a superoutburst of the AM CVn-type object SDSS J090221.35+381941.9 [J0902; orbital period 0.03355(6) d] in 2014 March-April. The entire outburst consisted of a precursor outburst and the main superoutburst, followed by a short rebrightening. During the rising branch of the main superoutburst, we detected growing superhumps (stage A superhumps) with a period of 0.03409(1) d. During the plateau phase of the superoutburst, superhumps with a shorter period (stage B superhumps) were observed. Using the orbital period and the period of the stage A superhumps, we were able to measure the dynamical precession rate of the accretion disk at the 3:1 resonance, and obtained a mass ratio (q) of 0.041(7). This is the first successful measurement of the mass ratio in an AM CVn-type object using the recently developed stage A superhump method. The value is generally in good agreement with the theoretical evolutionary model. The orbital period of J0902 is the longest among the outbursting AM CVn-type objects, and the borderline between the outbursting systems and systems with stable cool disks appears to be longer than had been supposed., Comment: 6 pages, 4 figures, accepted for publication in PASJ
Published: 2014
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21. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. VI: The Sixth Year (2013-2014)

Author: Kato, Taichi, Dubovsky, Pavol A., Kudzej, Igor, Hambsch, Franz-Josef, Miller, Ian, Ohshima, Tomohito, Nakata, Chikako, Kawabata, Miho, Nishino, Hirochika, Masumoto, Kazunari, Mizoguchi, Sahori, Yamanaka, Masayuki, Matsumoto, Katsura, Sakai, Daisuke, Fukushima, Daiki, Matsuura, Minami, Bouno, Genki, Takenaka, Megumi, Nakagawa, Shinichi, Noguchi, Ryo, Iino, Eriko, Pickard, Roger D., Maeda, Yutaka, Henden, Arne, Kasai, Kiyoshi, Kiyota, Seiichiro, Akazawa, Hidehiko, Imamura, Kazuyoshi, de Miguel, Enrique, Maehara, Hiroyuki, Monard, Berto, Pavlenko, Elena P., Antonyuk, Kirill, Pit, Nikolaj, Antonyuk, Oksana I., Baklanov, Aleksei V., Ruiz, Javier, Richmond, Michael, Oksanen, Arto, Harlingten, Caisey, Shugarov, Sergey Yu., Chochol, Drahomir, Masi, Gianluca, Nocentini, Francesca, Schmeer, Patrick, Bolt, Greg, Nelson, Peter, Ulowetz, Joseph, Sabo, Richard, Goff, William N., Stein, William, Michel, Raul, Dvorak, Shawn, Voloshina, Irina B., Metlov, Vladimir, Katysheva, Natalia, Neustroev, Vitaly V., Sjoberg, George, Littlefield, Colin, Debski, Bartlomiej, Sowicka, Paulina, Klimaszewski, Marcin, Curylo, Malgorzata, Morelle, Etienne, Curtis, Ivan A., Iwamatsu, Hidetoshi, Butterworth, Neil D., Andreev, Maksim V., Parakhin, Nikolai, Sklyanov, Aleksandr, Shiokawa, Kazuhiko, Novak, Rudolf, Irsmambetova, Tat'yana R., Itoh, Hiroshi, Ito, Yoshiharu, Hirosawa, Kenji, Denisenko, Denis, Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Itagaki, Koh-ichi, Stubbings, Rod, Ripero, Jose, Muyllaert, Eddy, Poyner, Gary, Kato, Taichi, Dubovsky, Pavol A., Kudzej, Igor, Hambsch, Franz-Josef, Miller, Ian, Ohshima, Tomohito, Nakata, Chikako, Kawabata, Miho, Nishino, Hirochika, Masumoto, Kazunari, Mizoguchi, Sahori, Yamanaka, Masayuki, Matsumoto, Katsura, Sakai, Daisuke, Fukushima, Daiki, Matsuura, Minami, Bouno, Genki, Takenaka, Megumi, Nakagawa, Shinichi, Noguchi, Ryo, Iino, Eriko, Pickard, Roger D., Maeda, Yutaka, Henden, Arne, Kasai, Kiyoshi, Kiyota, Seiichiro, Akazawa, Hidehiko, Imamura, Kazuyoshi, de Miguel, Enrique, Maehara, Hiroyuki, Monard, Berto, Pavlenko, Elena P., Antonyuk, Kirill, Pit, Nikolaj, Antonyuk, Oksana I., Baklanov, Aleksei V., Ruiz, Javier, Richmond, Michael, Oksanen, Arto, Harlingten, Caisey, Shugarov, Sergey Yu., Chochol, Drahomir, Masi, Gianluca, Nocentini, Francesca, Schmeer, Patrick, Bolt, Greg, Nelson, Peter, Ulowetz, Joseph, Sabo, Richard, Goff, William N., Stein, William, Michel, Raul, Dvorak, Shawn, Voloshina, Irina B., Metlov, Vladimir, Katysheva, Natalia, Neustroev, Vitaly V., Sjoberg, George, Littlefield, Colin, Debski, Bartlomiej, Sowicka, Paulina, Klimaszewski, Marcin, Curylo, Malgorzata, Morelle, Etienne, Curtis, Ivan A., Iwamatsu, Hidetoshi, Butterworth, Neil D., Andreev, Maksim V., Parakhin, Nikolai, Sklyanov, Aleksandr, Shiokawa, Kazuhiko, Novak, Rudolf, Irsmambetova, Tat'yana R., Itoh, Hiroshi, Ito, Yoshiharu, Hirosawa, Kenji, Denisenko, Denis, Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Itagaki, Koh-ichi, Stubbings, Rod, Ripero, Jose, Muyllaert, Eddy, and Poyner, Gary
Abstract: Continuing the project described by Kato et al. (2009, PASJ, 61, S395, arXiv:0905.1757), we collected times of superhump maxima for 56 SU UMa-type dwarf novae mainly observed during the 2013-2014 season and characterized these objects. We detected negative superhumps in VW Hyi and indicated that the low number of normal outbursts in some supercycle can be interpreted as a result of the disk tilt. This finding, combined with the Kepler observation of V1504 Cyg and V344 Lyr, suggests that the disk tilt is responsible for modulating the outburst pattern in SU UMa-type dwarf novae. We also studied the deeply eclipsing WZ Sge-type dwarf nova MASTER OT J005740.99+443101.5 and found evidence of a sharp eclipse during the phase of early superhumps. The profile can be reproduced by a combination of the eclipse of the axisymmetric disk and the uneclipsed light source of early superhumps. This finding confirms the lack of evince of a greatly enhanced hot spot during the early stage of WZ Sge-type outburst. We detected growing (stage A) superhumps in MN Dra and give a suggestion that some of SU UMa-type dwarf novae situated near the critical condition of tidal instability may show long-lasting stage A superhumps. The large negative period derivatives reported in such systems can be understood a result of the combination of stage A and B superhumps. The WZ Sge-type dwarf novae AL Com and ASASSN-13ck showed a long-lasting (plateau-type) rebrightening. In the early phase of the rebrightening, both objects showed a precursor-like outburst, suggesting that the long-lasting rebrightening is triggered by a precursor outburst., Comment: 73 pages, 88 figures, accepted for publication in PASJ
Published: 2014
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22. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. V: The Fifth Year (2012-2013)

Author: Kato, Taichi, Hambsch, Franz-Josef, Maehara, Hiroyuki, Masi, Gianluca, Nocentini, Francesca, Dubovsky, Pavol A., Kudzej, Igor, Imamura, Kazuyoshi, Ogi, Minako, Tanabe, Kenji, Akazawa, Hidehiko, Krajci, Thomas, Miller, Ian, de Miguel, Enrique, Henden, Arne, Littlefield, Colin, Noguchi, Ryo, Ishibashi, Takehiro, Ono, Rikako, Kawabata, Miho, Kobayashi, Hiroshi, Sakai, Daisuke, Nishino, Hirochika, Furukawa, Hisami, Masumoto, Kazunari, Matsumoto, Katsura, Ohshima, Tomohito, Nakata, Chikako, Honda, Satoshi, Kinugasa, Kenzo, Hashimoto, Osamu, Stein, William, Pickard, Roger D., Kiyota, Seiichiro, Pavlenko, Elena P., Antonyuk, Oksana I., Baklanov, Aleksei V., Antonyuk, Kirill, Samsonov, Denis, Pit, Nikolaj, Sosnovskij, Aleksei, Oksanen, Arto, Harlingten, Caisey, Tyyska, Jenni, Monard, Berto, Shugarov, Sergey Yu., Chochol, Drahomir, Kasai, Kiyoshi, Maeda, Yutaka, Hirosawa, Kenji, Itoh, Hiroshi, Sabo, Richard, Ulowetz, Joseph, Morelle, Etienne, Michel, Raul, Suarez, Genaro, James, Nick, Dvorak, Shawn, Voloshina, Irina B., Richmond, Michael, Staels, Bart, Boyd, David, Andreev, Maksim V., Parakhin, Nikolai, Katysheva, Natalia, Miyashita, Atsushi, Nakajima, Kazuhiro, Bolt, Greg, Padovan, Stefano, Nelson, Peter, Starkey, Donn R., Buczynski, Denis, Starr, Peter, Goff, William N., Denisenko, Denis, Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Itagaki, Koh-ichi, Kaneko, Shizuo, Stubbings, Rod, Muyllaert, Eddy, Shears, Jeremy, Schmeer, Patrick, Poyner, Gary, Marco, Miguel Rodriguez, Kato, Taichi, Hambsch, Franz-Josef, Maehara, Hiroyuki, Masi, Gianluca, Nocentini, Francesca, Dubovsky, Pavol A., Kudzej, Igor, Imamura, Kazuyoshi, Ogi, Minako, Tanabe, Kenji, Akazawa, Hidehiko, Krajci, Thomas, Miller, Ian, de Miguel, Enrique, Henden, Arne, Littlefield, Colin, Noguchi, Ryo, Ishibashi, Takehiro, Ono, Rikako, Kawabata, Miho, Kobayashi, Hiroshi, Sakai, Daisuke, Nishino, Hirochika, Furukawa, Hisami, Masumoto, Kazunari, Matsumoto, Katsura, Ohshima, Tomohito, Nakata, Chikako, Honda, Satoshi, Kinugasa, Kenzo, Hashimoto, Osamu, Stein, William, Pickard, Roger D., Kiyota, Seiichiro, Pavlenko, Elena P., Antonyuk, Oksana I., Baklanov, Aleksei V., Antonyuk, Kirill, Samsonov, Denis, Pit, Nikolaj, Sosnovskij, Aleksei, Oksanen, Arto, Harlingten, Caisey, Tyyska, Jenni, Monard, Berto, Shugarov, Sergey Yu., Chochol, Drahomir, Kasai, Kiyoshi, Maeda, Yutaka, Hirosawa, Kenji, Itoh, Hiroshi, Sabo, Richard, Ulowetz, Joseph, Morelle, Etienne, Michel, Raul, Suarez, Genaro, James, Nick, Dvorak, Shawn, Voloshina, Irina B., Richmond, Michael, Staels, Bart, Boyd, David, Andreev, Maksim V., Parakhin, Nikolai, Katysheva, Natalia, Miyashita, Atsushi, Nakajima, Kazuhiro, Bolt, Greg, Padovan, Stefano, Nelson, Peter, Starkey, Donn R., Buczynski, Denis, Starr, Peter, Goff, William N., Denisenko, Denis, Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Itagaki, Koh-ichi, Kaneko, Shizuo, Stubbings, Rod, Muyllaert, Eddy, Shears, Jeremy, Schmeer, Patrick, Poyner, Gary, and Marco, Miguel Rodriguez
Abstract: Continuing the project described by Kato et al. (2009a, arXiv:0905.1757), we collected times of superhump maxima for SU UMa-type dwarf novae mainly observed during the 2012-2013 season. We found three objects (V444 Peg, CSS J203937 and MASTER J212624) having strongly positive period derivatives despite the long orbital period (Porb). By using the period of growing stage (stage A) superhumps, we obtained mass ratios for six objects. We characterized nine new WZ Sge-type dwarf novae. We made a pilot survey of the decline rate of slowly fading part of SU UMa-type and WZ Sge-type outbursts. The decline time scale was found to generally follow the expected Porb^(1/4) dependence and WZ Sge-type outbursts also generally follow this trend. There are some objects which show slower decline rates, and we consider these objects good candidates for period bouncers. We also studied unusual behavior in some objects, including BK Lyn which made a transition from an ER UMa-type state to the novalike (standstill) state in 2013 and unusually frequent occurrence of superoutbursts in NY Ser and CR Boo. We applied least absolute shrinkage and selection operator (Lasso) power spectral analysis, which has been proven to be very effective in analyzing the Kepler data, to ground-based photometry of BK Lyn and detected the dramatic disappearance of the signal of negative superhumps in 2013. We suggested that the mass-transfer rates did not vary strongly between the ER UMa-type state and novalike state in BK Lyn, and this transition was less likely caused by a systematic variation of the mass-transfer rate., Comment: 83 pages, 95 figures, accepted for publication in PASJ
Published: 2013
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23. WZ Sge-type dwarf novae with multiple rebrightenings: MASTER OT J211258.65+242145.4 and MASTER OT J203749.39+552210.3

Author: Nakata, Chikako, Ohshima, Tomohito, Kato, Taichi, Nogami, Daisaku, Masi, Gianluca, de Miguel, Enrique, Ulowetz, Joseph, Littlefield, Colin, Goff, William N., Krajci, Thomas, Maehara, Hiroyuki, Stein, William, Sabo, Richard, Noguchi, Ryo, Ono, Rikako, Kawabata, Miho, Furukawa, Hisami, Matsumoto, Katsura, Ishibashi, Takehiro, Dubovsky, Pavol A., Kudzej, Igor, Dvorak, Shawn, Hambsch, Franz-Josef, Pickard, Roger D., Morelle, Etienne, Muyllaert, Eddy, Padovan, Stefano, Henden, Arne, Nakata, Chikako, Ohshima, Tomohito, Kato, Taichi, Nogami, Daisaku, Masi, Gianluca, de Miguel, Enrique, Ulowetz, Joseph, Littlefield, Colin, Goff, William N., Krajci, Thomas, Maehara, Hiroyuki, Stein, William, Sabo, Richard, Noguchi, Ryo, Ono, Rikako, Kawabata, Miho, Furukawa, Hisami, Matsumoto, Katsura, Ishibashi, Takehiro, Dubovsky, Pavol A., Kudzej, Igor, Dvorak, Shawn, Hambsch, Franz-Josef, Pickard, Roger D., Morelle, Etienne, Muyllaert, Eddy, Padovan, Stefano, and Henden, Arne
Abstract: We report on photometric observations of WZ Sge-type dwarf novae, MASTER OT J211258.65+242145.4 and MASTER OT J203749.39+552210.3 which underwent outbursts in 2012. Early superhumps were recorded in both systems. During superoutburst plateau, ordinary superhumps with a period of 0.060291(4) d (MASTER J211258) and of 0.061307(9) d (MASTER J203749) in average were observed. MASTER J211258 and MASTER J203749 exhibited eight and more than four post-superoutburst rebrightenings, respectively. In the final part of the superoutburst, an increase in the superhump periods was seen in both systems. We have made a survey of WZ Sge-type dwarf novae with multiple rebrightenings, and confirmed that the superhump periods of WZ Sge-type dwarf novae with multiple rebrightenings were longer than those of WZ Sge-type dwarf novae without a rebrightening. Although WZ Sge-type dwarf novae with multiple rebrightenings have been thought to be the good candidates for period bouncers based on their low mass ratio (q) from inferred from the period of fully grown (stage B) superhumps, our new method using the period of growing superhumps (stage A superhumps), however, implies higher q than those expected from stage B superhumps. These q values appear to be consistent with the duration of the stage A superoutbursts, which likely reflects the growth time of the 3:1 resonance. We present a working hypothesis that the small fractional superhump excesses for stage B superhumps in these systems may be explained as a result that a higher gas pressure effect works in these systems than in ordinary SU UMa-type dwarf novae. This result leads to a new picture that WZ Sge-type dwarf novae with multiple rebrightenings and SU UMa-type dwarf novae without a rebrightening (they are not period bouncers) are located in the same place on the evolutionary track.
Published: 2013
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24. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. V: The Fifth Year (2012-2013)

Author: Kato, Taichi, Hambsch, Franz-Josef, Maehara, Hiroyuki, Masi, Gianluca, Nocentini, Francesca, Dubovsky, Pavol A., Kudzej, Igor, Imamura, Kazuyoshi, Ogi, Minako, Tanabe, Kenji, Akazawa, Hidehiko, Krajci, Thomas, Miller, Ian, de Miguel, Enrique, Henden, Arne, Littlefield, Colin, Noguchi, Ryo, Ishibashi, Takehiro, Ono, Rikako, Kawabata, Miho, Kobayashi, Hiroshi, Sakai, Daisuke, Nishino, Hirochika, Furukawa, Hisami, Masumoto, Kazunari, Matsumoto, Katsura, Ohshima, Tomohito, Nakata, Chikako, Honda, Satoshi, Kinugasa, Kenzo, Hashimoto, Osamu, Stein, William, Pickard, Roger D., Kiyota, Seiichiro, Pavlenko, Elena P., Antonyuk, Oksana I., Baklanov, Aleksei V., Antonyuk, Kirill, Samsonov, Denis, Pit, Nikolaj, Sosnovskij, Aleksei, Oksanen, Arto, Harlingten, Caisey, Tyyska, Jenni, Monard, Berto, Shugarov, Sergey Yu., Chochol, Drahomir, Kasai, Kiyoshi, Maeda, Yutaka, Hirosawa, Kenji, Itoh, Hiroshi, Sabo, Richard, Ulowetz, Joseph, Morelle, Etienne, Michel, Raul, Suarez, Genaro, James, Nick, Dvorak, Shawn, Voloshina, Irina B., Richmond, Michael, Staels, Bart, Boyd, David, Andreev, Maksim V., Parakhin, Nikolai, Katysheva, Natalia, Miyashita, Atsushi, Nakajima, Kazuhiro, Bolt, Greg, Padovan, Stefano, Nelson, Peter, Starkey, Donn R., Buczynski, Denis, Starr, Peter, Goff, William N., Denisenko, Denis, Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Itagaki, Koh-ichi, Kaneko, Shizuo, Stubbings, Rod, Muyllaert, Eddy, Shears, Jeremy, Schmeer, Patrick, Poyner, Gary, Marco, Miguel Rodriguez, Kato, Taichi, Hambsch, Franz-Josef, Maehara, Hiroyuki, Masi, Gianluca, Nocentini, Francesca, Dubovsky, Pavol A., Kudzej, Igor, Imamura, Kazuyoshi, Ogi, Minako, Tanabe, Kenji, Akazawa, Hidehiko, Krajci, Thomas, Miller, Ian, de Miguel, Enrique, Henden, Arne, Littlefield, Colin, Noguchi, Ryo, Ishibashi, Takehiro, Ono, Rikako, Kawabata, Miho, Kobayashi, Hiroshi, Sakai, Daisuke, Nishino, Hirochika, Furukawa, Hisami, Masumoto, Kazunari, Matsumoto, Katsura, Ohshima, Tomohito, Nakata, Chikako, Honda, Satoshi, Kinugasa, Kenzo, Hashimoto, Osamu, Stein, William, Pickard, Roger D., Kiyota, Seiichiro, Pavlenko, Elena P., Antonyuk, Oksana I., Baklanov, Aleksei V., Antonyuk, Kirill, Samsonov, Denis, Pit, Nikolaj, Sosnovskij, Aleksei, Oksanen, Arto, Harlingten, Caisey, Tyyska, Jenni, Monard, Berto, Shugarov, Sergey Yu., Chochol, Drahomir, Kasai, Kiyoshi, Maeda, Yutaka, Hirosawa, Kenji, Itoh, Hiroshi, Sabo, Richard, Ulowetz, Joseph, Morelle, Etienne, Michel, Raul, Suarez, Genaro, James, Nick, Dvorak, Shawn, Voloshina, Irina B., Richmond, Michael, Staels, Bart, Boyd, David, Andreev, Maksim V., Parakhin, Nikolai, Katysheva, Natalia, Miyashita, Atsushi, Nakajima, Kazuhiro, Bolt, Greg, Padovan, Stefano, Nelson, Peter, Starkey, Donn R., Buczynski, Denis, Starr, Peter, Goff, William N., Denisenko, Denis, Kochanek, Christopher S., Shappee, Benjamin, Stanek, Krzysztof Z., Prieto, Jose L., Itagaki, Koh-ichi, Kaneko, Shizuo, Stubbings, Rod, Muyllaert, Eddy, Shears, Jeremy, Schmeer, Patrick, Poyner, Gary, and Marco, Miguel Rodriguez
Abstract: Continuing the project described by Kato et al. (2009a, arXiv:0905.1757), we collected times of superhump maxima for SU UMa-type dwarf novae mainly observed during the 2012-2013 season. We found three objects (V444 Peg, CSS J203937 and MASTER J212624) having strongly positive period derivatives despite the long orbital period (Porb). By using the period of growing stage (stage A) superhumps, we obtained mass ratios for six objects. We characterized nine new WZ Sge-type dwarf novae. We made a pilot survey of the decline rate of slowly fading part of SU UMa-type and WZ Sge-type outbursts. The decline time scale was found to generally follow the expected Porb^(1/4) dependence and WZ Sge-type outbursts also generally follow this trend. There are some objects which show slower decline rates, and we consider these objects good candidates for period bouncers. We also studied unusual behavior in some objects, including BK Lyn which made a transition from an ER UMa-type state to the novalike (standstill) state in 2013 and unusually frequent occurrence of superoutbursts in NY Ser and CR Boo. We applied least absolute shrinkage and selection operator (Lasso) power spectral analysis, which has been proven to be very effective in analyzing the Kepler data, to ground-based photometry of BK Lyn and detected the dramatic disappearance of the signal of negative superhumps in 2013. We suggested that the mass-transfer rates did not vary strongly between the ER UMa-type state and novalike state in BK Lyn, and this transition was less likely caused by a systematic variation of the mass-transfer rate., Comment: 83 pages, 95 figures, accepted for publication in PASJ
Published: 2013
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25. WZ Sge-type dwarf novae with multiple rebrightenings: MASTER OT J211258.65+242145.4 and MASTER OT J203749.39+552210.3

Author: Nakata, Chikako, Ohshima, Tomohito, Kato, Taichi, Nogami, Daisaku, Masi, Gianluca, de Miguel, Enrique, Ulowetz, Joseph, Littlefield, Colin, Goff, William N., Krajci, Thomas, Maehara, Hiroyuki, Stein, William, Sabo, Richard, Noguchi, Ryo, Ono, Rikako, Kawabata, Miho, Furukawa, Hisami, Matsumoto, Katsura, Ishibashi, Takehiro, Dubovsky, Pavol A., Kudzej, Igor, Dvorak, Shawn, Hambsch, Franz-Josef, Pickard, Roger D., Morelle, Etienne, Muyllaert, Eddy, Padovan, Stefano, Henden, Arne, Nakata, Chikako, Ohshima, Tomohito, Kato, Taichi, Nogami, Daisaku, Masi, Gianluca, de Miguel, Enrique, Ulowetz, Joseph, Littlefield, Colin, Goff, William N., Krajci, Thomas, Maehara, Hiroyuki, Stein, William, Sabo, Richard, Noguchi, Ryo, Ono, Rikako, Kawabata, Miho, Furukawa, Hisami, Matsumoto, Katsura, Ishibashi, Takehiro, Dubovsky, Pavol A., Kudzej, Igor, Dvorak, Shawn, Hambsch, Franz-Josef, Pickard, Roger D., Morelle, Etienne, Muyllaert, Eddy, Padovan, Stefano, and Henden, Arne
Abstract: We report on photometric observations of WZ Sge-type dwarf novae, MASTER OT J211258.65+242145.4 and MASTER OT J203749.39+552210.3 which underwent outbursts in 2012. Early superhumps were recorded in both systems. During superoutburst plateau, ordinary superhumps with a period of 0.060291(4) d (MASTER J211258) and of 0.061307(9) d (MASTER J203749) in average were observed. MASTER J211258 and MASTER J203749 exhibited eight and more than four post-superoutburst rebrightenings, respectively. In the final part of the superoutburst, an increase in the superhump periods was seen in both systems. We have made a survey of WZ Sge-type dwarf novae with multiple rebrightenings, and confirmed that the superhump periods of WZ Sge-type dwarf novae with multiple rebrightenings were longer than those of WZ Sge-type dwarf novae without a rebrightening. Although WZ Sge-type dwarf novae with multiple rebrightenings have been thought to be the good candidates for period bouncers based on their low mass ratio (q) from inferred from the period of fully grown (stage B) superhumps, our new method using the period of growing superhumps (stage A superhumps), however, implies higher q than those expected from stage B superhumps. These q values appear to be consistent with the duration of the stage A superoutbursts, which likely reflects the growth time of the 3:1 resonance. We present a working hypothesis that the small fractional superhump excesses for stage B superhumps in these systems may be explained as a result that a higher gas pressure effect works in these systems than in ordinary SU UMa-type dwarf novae. This result leads to a new picture that WZ Sge-type dwarf novae with multiple rebrightenings and SU UMa-type dwarf novae without a rebrightening (they are not period bouncers) are located in the same place on the evolutionary track.
Published: 2013
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26. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. IV: The Fourth Year (2011-2012)

Author: Kato, Taichi, Hambsch, Franz-Josef, Maehara, Hiroyuki, Masi, Gianluca, Miller, Ian, Noguchi, Ryo, Akasaka, Chihiro, Aoki, Tomoya, Kobayashi, Hiroshi, Matsumoto, Katsura, Nakagawa, Shinichi, Nakazato, Takuma, Nomoto, Takashi, Ogura, Kazuyuki, Ono, Rikako, Taniuchi, Keisuke, Stein, William, Henden, Arne, de Miguel, Enrique, Kiyota, Seiichiro, Dubovsky, Pavol A., Kudzej, Igor, Imamura, Kazuyoshi, Akazawa, Hidehiko, Takagi, Ryosuke, Wakabayashi, Yuya, Ogi, Minako, Tanabe, Kenji, Ulowetz, Joseph, Morelle, Etienne, Pickard, Roger D., Ohshima, Tomohito, Kasai, Kiyoshi, Pavlenko, Elena P., Antonyuk, Oksana I., Baklanov, Aleksei V., Antonyuk, Kirill, Samsonov, Denis, Pit, Nikolaj, Sosnovskij, Aleksei, Littlefield, Colin, Sabo, Richard, Ruiz, Javier, Krajci, Thomas, Dvorak, Shawn, Oksanen, Arto, Hirosawa, Kenji, Goff, William N., Monard, Berto, Shears, Jeremy, Boyd, David, Voloshina, Irina B., Shugarov, Sergey Yu., Chochol, Drahomir, Miyashita, Atsushi, Pietz, Jochen, Katysheva, Natalia, Itoh, Hiroshi, Bolt, Greg, Andreev, Maksim V., Parakhin, Nikolai, Malanushenko, Viktor, Martinelli, Fabio, Denisenko, Denis, Stockdale, Chris, Starr, Peter, Simonsen, Mike, Tristram, Paul. J., Fukui, Akihiko, Tordai, Tamas, Fidrich, Robert, Paxson, Kevin B., Itagaki, Koh-ichi, Nakashima, Youichirou, Yoshida, Seiichi, Nishimura, Hideo, Kryachko, Timur V., Samokhvalov, Andrey V., Korotkiy, Stanislav A., Satovski, Boris L., Stubbings, Rod, Poyner, Gary, Muyllaert, Eddy, Gerke, Vladimir, MacDonald II, Walter, Linnolt, Michael, Maeda, Yutaka, Hautecler, Hubert, Kato, Taichi, Hambsch, Franz-Josef, Maehara, Hiroyuki, Masi, Gianluca, Miller, Ian, Noguchi, Ryo, Akasaka, Chihiro, Aoki, Tomoya, Kobayashi, Hiroshi, Matsumoto, Katsura, Nakagawa, Shinichi, Nakazato, Takuma, Nomoto, Takashi, Ogura, Kazuyuki, Ono, Rikako, Taniuchi, Keisuke, Stein, William, Henden, Arne, de Miguel, Enrique, Kiyota, Seiichiro, Dubovsky, Pavol A., Kudzej, Igor, Imamura, Kazuyoshi, Akazawa, Hidehiko, Takagi, Ryosuke, Wakabayashi, Yuya, Ogi, Minako, Tanabe, Kenji, Ulowetz, Joseph, Morelle, Etienne, Pickard, Roger D., Ohshima, Tomohito, Kasai, Kiyoshi, Pavlenko, Elena P., Antonyuk, Oksana I., Baklanov, Aleksei V., Antonyuk, Kirill, Samsonov, Denis, Pit, Nikolaj, Sosnovskij, Aleksei, Littlefield, Colin, Sabo, Richard, Ruiz, Javier, Krajci, Thomas, Dvorak, Shawn, Oksanen, Arto, Hirosawa, Kenji, Goff, William N., Monard, Berto, Shears, Jeremy, Boyd, David, Voloshina, Irina B., Shugarov, Sergey Yu., Chochol, Drahomir, Miyashita, Atsushi, Pietz, Jochen, Katysheva, Natalia, Itoh, Hiroshi, Bolt, Greg, Andreev, Maksim V., Parakhin, Nikolai, Malanushenko, Viktor, Martinelli, Fabio, Denisenko, Denis, Stockdale, Chris, Starr, Peter, Simonsen, Mike, Tristram, Paul. J., Fukui, Akihiko, Tordai, Tamas, Fidrich, Robert, Paxson, Kevin B., Itagaki, Koh-ichi, Nakashima, Youichirou, Yoshida, Seiichi, Nishimura, Hideo, Kryachko, Timur V., Samokhvalov, Andrey V., Korotkiy, Stanislav A., Satovski, Boris L., Stubbings, Rod, Poyner, Gary, Muyllaert, Eddy, Gerke, Vladimir, MacDonald II, Walter, Linnolt, Michael, Maeda, Yutaka, and Hautecler, Hubert
Abstract: Continuing the project described by Kato et al. (2009, arXiv:0905.1757), we studied 86 SU UMa-type dwarf novae. We confirmed the general trends such as the relation between period derivatives and orbital periods. There are some systems showing positive period derivatives despite the long orbital periods. We observed the 2011 outburst of the WZ Sge-type dwarf nova BW Scl, and recorded an O-C diagram similar to those of previously known WZ Sge-type dwarf novae. The WZ Sge-type dwarf nova OT J184228.1+483742 showed an unusual pattern of double outbursts composed of an outburst with early superhumps and one with ordinary superhumps. We propose an interpretation that a very small growth rate of the 3:1 resonance due to an extremely low mass-ratio led to a quenching of the superoutburst before the ordinary superhumps appeared. We studied ER UMa-type dwarf novae and found that V1159 Ori showed positive superhumps similar to ER UMa in the 1990s. The recently recognized ER UMa-type object BK Lyn dominantly showed negative superhumps, and its behavior was very similar to the present-day state of ER UMa. The pattern of period variations in AM CVn-type objects were very similar to short-period hydrogen-rich SU UMa-type dwarf novae, making them helium analogue of hydrogen-rich SU UMa-type dwarf novae. SBS 1108+574, a peculiar hydrogen-rich dwarf nova below the period minimum, showed a very similar pattern of period variations to those of short-period SU UMa-type dwarf novae. The mass-ratio derived from the detected orbital period suggests that this secondary is a somewhat evolved star whose hydrogen envelope was mostly stripped during the mass-exchange. CC Scl, MASTER OT J072948.66+593824.4 and OT J173516.9+154708 showed only low-amplitude superhumps with complex profiles. These superhumps are likely a combination of closely separated two periods., Comment: 81 pages, 92 figures, PASJ in press, correction in the author list and text
Published: 2012
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27. The first confirmed superoutburst of the dwarf nova GALEX J215818.5+241924

Author: Shears, Jeremy, Koff, Robert, Masi, Gianluca, de Miguel, Enrique, Miller, Ian, Roberts, George, Sabo, Richard, Stein, William, Ulowetz, Joseph, Shears, Jeremy, Koff, Robert, Masi, Gianluca, de Miguel, Enrique, Miller, Ian, Roberts, George, Sabo, Richard, Stein, William, and Ulowetz, Joseph
Abstract: In 2011 October an optical transient was reported in Pegasus as a possible nova. The object had an ultraviolet counterpart, GALEX J215818.5+241924. In this paper we present follow-up photometry of the object which revealed the presence of superhumps, with peak-to-peak amplitude of up to 0.22 magnitudes, diagnostic of it being a member of the SU UMa family of dwarf novae. The outburst amplitude was 4.6 magnitudes and it lasted at least 10 days, with a maximum brightness of magnitude 14.3. We determined the mean superhump period from our first 5 nights of observations as Psh = 0.06728(21) d. However analysis of the O-C residuals showed a dramatic evolution in Psh during the outburst. During the first part of the plateau phase the period increased with dPsh/dt = +2.67(15) x 10-4. There was then an abrupt change following which the period decreased with dPsh/dt = -2.08(9)x 10-4. We found a signal in the power spectrum of the photometry which we tentatively interpret as the orbital signal with Porb = 0.06606(35) d. Thus the superhump period excess was epsilon = 0.020(8), such value being consistent with other SU UMa systems of similar orbital period., Comment: Accepted for publication in the Journal of the British Astronomical Association. 10 pages, 3 figures. arXiv admin note: text overlap with arXiv:1005.5378. Have corrected outburst amplitude, reworded the first 2 sentences of the Abstract for clarity and solved some typos
Published: 2012

28. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. IV: The Fourth Year (2011-2012)

Author: Kato, Taichi, Hambsch, Franz-Josef, Maehara, Hiroyuki, Masi, Gianluca, Miller, Ian, Noguchi, Ryo, Akasaka, Chihiro, Aoki, Tomoya, Kobayashi, Hiroshi, Matsumoto, Katsura, Nakagawa, Shinichi, Nakazato, Takuma, Nomoto, Takashi, Ogura, Kazuyuki, Ono, Rikako, Taniuchi, Keisuke, Stein, William, Henden, Arne, de Miguel, Enrique, Kiyota, Seiichiro, Dubovsky, Pavol A., Kudzej, Igor, Imamura, Kazuyoshi, Akazawa, Hidehiko, Takagi, Ryosuke, Wakabayashi, Yuya, Ogi, Minako, Tanabe, Kenji, Ulowetz, Joseph, Morelle, Etienne, Pickard, Roger D., Ohshima, Tomohito, Kasai, Kiyoshi, Pavlenko, Elena P., Antonyuk, Oksana I., Baklanov, Aleksei V., Antonyuk, Kirill, Samsonov, Denis, Pit, Nikolaj, Sosnovskij, Aleksei, Littlefield, Colin, Sabo, Richard, Ruiz, Javier, Krajci, Thomas, Dvorak, Shawn, Oksanen, Arto, Hirosawa, Kenji, Goff, William N., Monard, Berto, Shears, Jeremy, Boyd, David, Voloshina, Irina B., Shugarov, Sergey Yu., Chochol, Drahomir, Miyashita, Atsushi, Pietz, Jochen, Katysheva, Natalia, Itoh, Hiroshi, Bolt, Greg, Andreev, Maksim V., Parakhin, Nikolai, Malanushenko, Viktor, Martinelli, Fabio, Denisenko, Denis, Stockdale, Chris, Starr, Peter, Simonsen, Mike, Tristram, Paul. J., Fukui, Akihiko, Tordai, Tamas, Fidrich, Robert, Paxson, Kevin B., Itagaki, Koh-ichi, Nakashima, Youichirou, Yoshida, Seiichi, Nishimura, Hideo, Kryachko, Timur V., Samokhvalov, Andrey V., Korotkiy, Stanislav A., Satovski, Boris L., Stubbings, Rod, Poyner, Gary, Muyllaert, Eddy, Gerke, Vladimir, MacDonald II, Walter, Linnolt, Michael, Maeda, Yutaka, Hautecler, Hubert, Kato, Taichi, Hambsch, Franz-Josef, Maehara, Hiroyuki, Masi, Gianluca, Miller, Ian, Noguchi, Ryo, Akasaka, Chihiro, Aoki, Tomoya, Kobayashi, Hiroshi, Matsumoto, Katsura, Nakagawa, Shinichi, Nakazato, Takuma, Nomoto, Takashi, Ogura, Kazuyuki, Ono, Rikako, Taniuchi, Keisuke, Stein, William, Henden, Arne, de Miguel, Enrique, Kiyota, Seiichiro, Dubovsky, Pavol A., Kudzej, Igor, Imamura, Kazuyoshi, Akazawa, Hidehiko, Takagi, Ryosuke, Wakabayashi, Yuya, Ogi, Minako, Tanabe, Kenji, Ulowetz, Joseph, Morelle, Etienne, Pickard, Roger D., Ohshima, Tomohito, Kasai, Kiyoshi, Pavlenko, Elena P., Antonyuk, Oksana I., Baklanov, Aleksei V., Antonyuk, Kirill, Samsonov, Denis, Pit, Nikolaj, Sosnovskij, Aleksei, Littlefield, Colin, Sabo, Richard, Ruiz, Javier, Krajci, Thomas, Dvorak, Shawn, Oksanen, Arto, Hirosawa, Kenji, Goff, William N., Monard, Berto, Shears, Jeremy, Boyd, David, Voloshina, Irina B., Shugarov, Sergey Yu., Chochol, Drahomir, Miyashita, Atsushi, Pietz, Jochen, Katysheva, Natalia, Itoh, Hiroshi, Bolt, Greg, Andreev, Maksim V., Parakhin, Nikolai, Malanushenko, Viktor, Martinelli, Fabio, Denisenko, Denis, Stockdale, Chris, Starr, Peter, Simonsen, Mike, Tristram, Paul. J., Fukui, Akihiko, Tordai, Tamas, Fidrich, Robert, Paxson, Kevin B., Itagaki, Koh-ichi, Nakashima, Youichirou, Yoshida, Seiichi, Nishimura, Hideo, Kryachko, Timur V., Samokhvalov, Andrey V., Korotkiy, Stanislav A., Satovski, Boris L., Stubbings, Rod, Poyner, Gary, Muyllaert, Eddy, Gerke, Vladimir, MacDonald II, Walter, Linnolt, Michael, Maeda, Yutaka, and Hautecler, Hubert
Abstract: Continuing the project described by Kato et al. (2009, arXiv:0905.1757), we studied 86 SU UMa-type dwarf novae. We confirmed the general trends such as the relation between period derivatives and orbital periods. There are some systems showing positive period derivatives despite the long orbital periods. We observed the 2011 outburst of the WZ Sge-type dwarf nova BW Scl, and recorded an O-C diagram similar to those of previously known WZ Sge-type dwarf novae. The WZ Sge-type dwarf nova OT J184228.1+483742 showed an unusual pattern of double outbursts composed of an outburst with early superhumps and one with ordinary superhumps. We propose an interpretation that a very small growth rate of the 3:1 resonance due to an extremely low mass-ratio led to a quenching of the superoutburst before the ordinary superhumps appeared. We studied ER UMa-type dwarf novae and found that V1159 Ori showed positive superhumps similar to ER UMa in the 1990s. The recently recognized ER UMa-type object BK Lyn dominantly showed negative superhumps, and its behavior was very similar to the present-day state of ER UMa. The pattern of period variations in AM CVn-type objects were very similar to short-period hydrogen-rich SU UMa-type dwarf novae, making them helium analogue of hydrogen-rich SU UMa-type dwarf novae. SBS 1108+574, a peculiar hydrogen-rich dwarf nova below the period minimum, showed a very similar pattern of period variations to those of short-period SU UMa-type dwarf novae. The mass-ratio derived from the detected orbital period suggests that this secondary is a somewhat evolved star whose hydrogen envelope was mostly stripped during the mass-exchange. CC Scl, MASTER OT J072948.66+593824.4 and OT J173516.9+154708 showed only low-amplitude superhumps with complex profiles. These superhumps are likely a combination of closely separated two periods., Comment: 81 pages, 92 figures, PASJ in press, correction in the author list and text
Published: 2012
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29. The first confirmed superoutburst of the dwarf nova GALEX J215818.5+241924

Author: Shears, Jeremy, Koff, Robert, Masi, Gianluca, de Miguel, Enrique, Miller, Ian, Roberts, George, Sabo, Richard, Stein, William, Ulowetz, Joseph, Shears, Jeremy, Koff, Robert, Masi, Gianluca, de Miguel, Enrique, Miller, Ian, Roberts, George, Sabo, Richard, Stein, William, and Ulowetz, Joseph
Abstract: In 2011 October an optical transient was reported in Pegasus as a possible nova. The object had an ultraviolet counterpart, GALEX J215818.5+241924. In this paper we present follow-up photometry of the object which revealed the presence of superhumps, with peak-to-peak amplitude of up to 0.22 magnitudes, diagnostic of it being a member of the SU UMa family of dwarf novae. The outburst amplitude was 4.6 magnitudes and it lasted at least 10 days, with a maximum brightness of magnitude 14.3. We determined the mean superhump period from our first 5 nights of observations as Psh = 0.06728(21) d. However analysis of the O-C residuals showed a dramatic evolution in Psh during the outburst. During the first part of the plateau phase the period increased with dPsh/dt = +2.67(15) x 10-4. There was then an abrupt change following which the period decreased with dPsh/dt = -2.08(9)x 10-4. We found a signal in the power spectrum of the photometry which we tentatively interpret as the orbital signal with Porb = 0.06606(35) d. Thus the superhump period excess was epsilon = 0.020(8), such value being consistent with other SU UMa systems of similar orbital period., Comment: Accepted for publication in the Journal of the British Astronomical Association. 10 pages, 3 figures. arXiv admin note: text overlap with arXiv:1005.5378. Have corrected outburst amplitude, reworded the first 2 sentences of the Abstract for clarity and solved some typos
Published: 2012

30. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. III: The Third Year (2010--2011)

Author: Kato, Taichi, Maehara, Hiroyuki, Miller, Ian, Ohshima, Tomohito, de Miguel, Enrique, Tanabe, Kenji, Imamura, Kazuyoshi, Akazawa, Hidehiko, Kunitomi, Nanae, Takagi, Ryosuke, Nose, Mikiha, Hambsch, Franz-Josef, Kiyota, Seiichiro, Pavlenko, Elena P., Baklanov, Aleksei V., Antonyuk, Oksana I., Samsonov, Denis, Sosnovskij, Aleksei, Antonyuk, Kirill, Andreev, Maksim V., Morelle, Etienne, Dubovsky, Pavol A., Kudzej, Igor, Oksanen, Arto, Masi, Gianluca, Krajci, Thomas, Pickard, Roger D., Sabo, Richard, Itoh, Hiroshi, Stein, William, Dvorak, Shawn, Henden, Arne, Nakagawa, Shinichi, Noguchi, Ryo, Iino, Eriko, Matsumoto, Katsura, Nishitani, Hiroki, Aoki, Tomoya, Kobayashi, Hiroshi, Akasaka, Chihiro, Bolt, Greg, Shears, Jeremy, Ruiz, Javier, Shugarov, Sergey Yu., Chochol, Drahomir, Parakhin, Nikolai A., Monard, Berto, Shiokawa, Kazuhiko, Kasai, Kiyoshi, Staels, Bart, Miyashita, Atsushi, Starkey, Donn R., Ogmen, Yenal, Littlefield, Colin, Katysheva, Natalia, Sergey, Ivan M., Denisenko, Denis, Tordai, Tamas, Fidrich, Robert, Goranskij, Vitaly P., Virtanen, Jani, Crawford, Tim, Pietz, Jochen, Koff, Robert A., Boyd, David, Brady, Steve, James, Nick, Goff, William N., Itagaki, Koh-ichi, Nishimura, Hideo, Nakashima, Youichirou, Yoshida, Seiichi, Stubbings, Rod, Poyner, Gary, Maeda, Yutaka, Korotkiy, Stanislav A., Sokolovsky, Kirill V., Ueda, Seiji, Kato, Taichi, Maehara, Hiroyuki, Miller, Ian, Ohshima, Tomohito, de Miguel, Enrique, Tanabe, Kenji, Imamura, Kazuyoshi, Akazawa, Hidehiko, Kunitomi, Nanae, Takagi, Ryosuke, Nose, Mikiha, Hambsch, Franz-Josef, Kiyota, Seiichiro, Pavlenko, Elena P., Baklanov, Aleksei V., Antonyuk, Oksana I., Samsonov, Denis, Sosnovskij, Aleksei, Antonyuk, Kirill, Andreev, Maksim V., Morelle, Etienne, Dubovsky, Pavol A., Kudzej, Igor, Oksanen, Arto, Masi, Gianluca, Krajci, Thomas, Pickard, Roger D., Sabo, Richard, Itoh, Hiroshi, Stein, William, Dvorak, Shawn, Henden, Arne, Nakagawa, Shinichi, Noguchi, Ryo, Iino, Eriko, Matsumoto, Katsura, Nishitani, Hiroki, Aoki, Tomoya, Kobayashi, Hiroshi, Akasaka, Chihiro, Bolt, Greg, Shears, Jeremy, Ruiz, Javier, Shugarov, Sergey Yu., Chochol, Drahomir, Parakhin, Nikolai A., Monard, Berto, Shiokawa, Kazuhiko, Kasai, Kiyoshi, Staels, Bart, Miyashita, Atsushi, Starkey, Donn R., Ogmen, Yenal, Littlefield, Colin, Katysheva, Natalia, Sergey, Ivan M., Denisenko, Denis, Tordai, Tamas, Fidrich, Robert, Goranskij, Vitaly P., Virtanen, Jani, Crawford, Tim, Pietz, Jochen, Koff, Robert A., Boyd, David, Brady, Steve, James, Nick, Goff, William N., Itagaki, Koh-ichi, Nishimura, Hideo, Nakashima, Youichirou, Yoshida, Seiichi, Stubbings, Rod, Poyner, Gary, Maeda, Yutaka, Korotkiy, Stanislav A., Sokolovsky, Kirill V., and Ueda, Seiji
Abstract: Continuing the project described by Kato et al. (2009, PASJ 61, S395, arXiv:0905.1757), we collected times of superhump maxima for 51 SU UMa-type dwarf novae mainly observed during the 2010-2011 season. Although most of the new data for systems with short superhump periods basically confirmed the findings by Kato et al. (2009) and Kato et al. (2010, PASJ 62, 1525, arXiv:1009.5444), the long-period system GX Cas showed an exceptionally large positive period derivative. An analysis of public Kepler data of V344 Lyr and V1504 Cyg yielded less striking stage transitions. In V344 Lyr, there was prominent secondary component growing during the late stage of superoutbursts, and the component persisted at least for two more cycles of successive normal outbursts. We also investigated the superoutbursts of two conspicuous eclipsing objects: HT Cas and the WZ Sge-type object SDSS J080434.20+510349.2. Strong beat phenomena were detected in both objects, and late-stage superhumps in the latter object had an almost constant luminosity during the repeated rebrightenings. The WZ Sge-type object SDSS J133941.11+484727.5 showed a phase reversal around the rapid fading from the superoutburst. The object showed a prominent beat phenomenon even after the end of the superoutburst. A pilot study of superhump amplitudes indicated that the amplitudes of superhumps are strongly correlated with orbital periods, and the dependence on the inclination is weak in systems with inclinations smaller than 80 deg., Comment: 87 pages, 92 figures, Accepted for publication in PASJ, correction in the author list and text
Published: 2011
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31. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. III: The Third Year (2010--2011)

Author: Kato, Taichi, Maehara, Hiroyuki, Miller, Ian, Ohshima, Tomohito, de Miguel, Enrique, Tanabe, Kenji, Imamura, Kazuyoshi, Akazawa, Hidehiko, Kunitomi, Nanae, Takagi, Ryosuke, Nose, Mikiha, Hambsch, Franz-Josef, Kiyota, Seiichiro, Pavlenko, Elena P., Baklanov, Aleksei V., Antonyuk, Oksana I., Samsonov, Denis, Sosnovskij, Aleksei, Antonyuk, Kirill, Andreev, Maksim V., Morelle, Etienne, Dubovsky, Pavol A., Kudzej, Igor, Oksanen, Arto, Masi, Gianluca, Krajci, Thomas, Pickard, Roger D., Sabo, Richard, Itoh, Hiroshi, Stein, William, Dvorak, Shawn, Henden, Arne, Nakagawa, Shinichi, Noguchi, Ryo, Iino, Eriko, Matsumoto, Katsura, Nishitani, Hiroki, Aoki, Tomoya, Kobayashi, Hiroshi, Akasaka, Chihiro, Bolt, Greg, Shears, Jeremy, Ruiz, Javier, Shugarov, Sergey Yu., Chochol, Drahomir, Parakhin, Nikolai A., Monard, Berto, Shiokawa, Kazuhiko, Kasai, Kiyoshi, Staels, Bart, Miyashita, Atsushi, Starkey, Donn R., Ogmen, Yenal, Littlefield, Colin, Katysheva, Natalia, Sergey, Ivan M., Denisenko, Denis, Tordai, Tamas, Fidrich, Robert, Goranskij, Vitaly P., Virtanen, Jani, Crawford, Tim, Pietz, Jochen, Koff, Robert A., Boyd, David, Brady, Steve, James, Nick, Goff, William N., Itagaki, Koh-ichi, Nishimura, Hideo, Nakashima, Youichirou, Yoshida, Seiichi, Stubbings, Rod, Poyner, Gary, Maeda, Yutaka, Korotkiy, Stanislav A., Sokolovsky, Kirill V., Ueda, Seiji, Kato, Taichi, Maehara, Hiroyuki, Miller, Ian, Ohshima, Tomohito, de Miguel, Enrique, Tanabe, Kenji, Imamura, Kazuyoshi, Akazawa, Hidehiko, Kunitomi, Nanae, Takagi, Ryosuke, Nose, Mikiha, Hambsch, Franz-Josef, Kiyota, Seiichiro, Pavlenko, Elena P., Baklanov, Aleksei V., Antonyuk, Oksana I., Samsonov, Denis, Sosnovskij, Aleksei, Antonyuk, Kirill, Andreev, Maksim V., Morelle, Etienne, Dubovsky, Pavol A., Kudzej, Igor, Oksanen, Arto, Masi, Gianluca, Krajci, Thomas, Pickard, Roger D., Sabo, Richard, Itoh, Hiroshi, Stein, William, Dvorak, Shawn, Henden, Arne, Nakagawa, Shinichi, Noguchi, Ryo, Iino, Eriko, Matsumoto, Katsura, Nishitani, Hiroki, Aoki, Tomoya, Kobayashi, Hiroshi, Akasaka, Chihiro, Bolt, Greg, Shears, Jeremy, Ruiz, Javier, Shugarov, Sergey Yu., Chochol, Drahomir, Parakhin, Nikolai A., Monard, Berto, Shiokawa, Kazuhiko, Kasai, Kiyoshi, Staels, Bart, Miyashita, Atsushi, Starkey, Donn R., Ogmen, Yenal, Littlefield, Colin, Katysheva, Natalia, Sergey, Ivan M., Denisenko, Denis, Tordai, Tamas, Fidrich, Robert, Goranskij, Vitaly P., Virtanen, Jani, Crawford, Tim, Pietz, Jochen, Koff, Robert A., Boyd, David, Brady, Steve, James, Nick, Goff, William N., Itagaki, Koh-ichi, Nishimura, Hideo, Nakashima, Youichirou, Yoshida, Seiichi, Stubbings, Rod, Poyner, Gary, Maeda, Yutaka, Korotkiy, Stanislav A., Sokolovsky, Kirill V., and Ueda, Seiji
Abstract: Continuing the project described by Kato et al. (2009, PASJ 61, S395, arXiv:0905.1757), we collected times of superhump maxima for 51 SU UMa-type dwarf novae mainly observed during the 2010-2011 season. Although most of the new data for systems with short superhump periods basically confirmed the findings by Kato et al. (2009) and Kato et al. (2010, PASJ 62, 1525, arXiv:1009.5444), the long-period system GX Cas showed an exceptionally large positive period derivative. An analysis of public Kepler data of V344 Lyr and V1504 Cyg yielded less striking stage transitions. In V344 Lyr, there was prominent secondary component growing during the late stage of superoutbursts, and the component persisted at least for two more cycles of successive normal outbursts. We also investigated the superoutbursts of two conspicuous eclipsing objects: HT Cas and the WZ Sge-type object SDSS J080434.20+510349.2. Strong beat phenomena were detected in both objects, and late-stage superhumps in the latter object had an almost constant luminosity during the repeated rebrightenings. The WZ Sge-type object SDSS J133941.11+484727.5 showed a phase reversal around the rapid fading from the superoutburst. The object showed a prominent beat phenomenon even after the end of the superoutburst. A pilot study of superhump amplitudes indicated that the amplitudes of superhumps are strongly correlated with orbital periods, and the dependence on the inclination is weak in systems with inclinations smaller than 80 deg., Comment: 87 pages, 92 figures, Accepted for publication in PASJ, correction in the author list and text
Published: 2011
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32. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. II: The Second Year (2009-2010)

Author: Kato, Taichi, Maehara, Hiroyuki, Uemura, Makoto, Henden, Arne, de Miguel, Enrique, Miller, Ian, Dubovsky, Pavol A., Kudzej, Igor, Kiyota, Seiichiro, Hambsch, Franz-Josef, Tanabe, Kenji, Imamura, Kazuyoshi, Kunitomi, Nanae, Takagi, Ryosuke, Nose, Mikiha, Akazawa, Hidehiko, Masi, Gianluca, Nakagawa, Shinichi, Iino, Eriko, Noguchi, Ryo, Matsumoto, Katsura, Fujii, Daichi, Kobayashi, Hiroshi, Ogura, Kazuyuki, Ohtomo, Sachi, Yamashita, Kousei, Yanagisawa, Hirofumi, Itoh, Hiroshi, Bolt, Greg, Monard, Berto, Ohshima, Tomohito, Shears, Jeremy, Ruiz, Javier, Imada, Akira, Oksanen, Arto, Nelson, Peter, Gomez, Tomas L., Staels, Bart, Boyd, David, Voloshina, Irina B., Krajci, Thomas, Crawford, Tim, Stockdale, Chris, Richmond, Michael, Morelle, Etienne, Novak, Rudolf, Nogami, Daisaku, Ishioka, Ryoko, Brady, Steve, Simonsen, Mike, Pavlenko, Elena P., Ringwald, Frederick A., Kuramoto, Tetsuya, Miyashita, Atsushi, Pickard, Roger D., Hynek, Tomas, Dvorak, Shawn, Stubbings, Rod, Muyllaert, Eddy, Kato, Taichi, Maehara, Hiroyuki, Uemura, Makoto, Henden, Arne, de Miguel, Enrique, Miller, Ian, Dubovsky, Pavol A., Kudzej, Igor, Kiyota, Seiichiro, Hambsch, Franz-Josef, Tanabe, Kenji, Imamura, Kazuyoshi, Kunitomi, Nanae, Takagi, Ryosuke, Nose, Mikiha, Akazawa, Hidehiko, Masi, Gianluca, Nakagawa, Shinichi, Iino, Eriko, Noguchi, Ryo, Matsumoto, Katsura, Fujii, Daichi, Kobayashi, Hiroshi, Ogura, Kazuyuki, Ohtomo, Sachi, Yamashita, Kousei, Yanagisawa, Hirofumi, Itoh, Hiroshi, Bolt, Greg, Monard, Berto, Ohshima, Tomohito, Shears, Jeremy, Ruiz, Javier, Imada, Akira, Oksanen, Arto, Nelson, Peter, Gomez, Tomas L., Staels, Bart, Boyd, David, Voloshina, Irina B., Krajci, Thomas, Crawford, Tim, Stockdale, Chris, Richmond, Michael, Morelle, Etienne, Novak, Rudolf, Nogami, Daisaku, Ishioka, Ryoko, Brady, Steve, Simonsen, Mike, Pavlenko, Elena P., Ringwald, Frederick A., Kuramoto, Tetsuya, Miyashita, Atsushi, Pickard, Roger D., Hynek, Tomas, Dvorak, Shawn, Stubbings, Rod, and Muyllaert, Eddy
Abstract: As an extension of the project in Kato et al. (2009, arXiv:0905.1757), we collected times of superhump maxima for 61 SU UMa-type dwarf novae mainly observed during the 2009-2010 season. The newly obtained data confirmed the basic findings reported in Kato et al. (2009): the presence of stages A-C, as well as the predominance of positive period derivatives during stage B in systems with superhump periods shorter than 0.07 d. There was a systematic difference in period derivatives for systems with superhump periods longer than 0.075 d between this study and Kato et al. (2009). We suggest that this difference is possibly caused by the relative lack of frequently outbursting SU UMa-type dwarf novae in this period regime in the present study. We recorded a strong beat phenomenon during the 2009 superoutburst of IY UMa. The close correlation between the beat period and superhump period suggests that the changing angular velocity of the apsidal motion of the elliptical disk is responsible for the variation of superhump periods. We also described three new WZ Sge-type objects with established early superhumps and one with likely early superhumps. We also suggest that two systems, VX For and EL UMa, are WZ Sge-type dwarf novae with multiple rebrightenings. The O-C variation in OT J213806.6+261957 suggests that the frequent absence of rebrightenings in very short-Porb objects can be a result of sustained superoutburst plateau at the epoch when usual SU UMa-type dwarf novae return to quiescence preceding a rebrightening. We also present a formulation for a variety of Bayesian extension to traditional period analyses., Comment: 63 pages, 77 figures, 1 appendix, Accepted for publication in PASJ, data correction
Published: 2010
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33. The orbital and superhump periods of the deeply eclipsing dwarf nova SDSS J150240.98+333423.9

Author: Shears, Jeremy, Campbell, Tut, Foote, Jerry, Garrett, Russ, Hager, Tim, Julian, William Mack, Kemp, Jonathan, Masi, Gianluca, Miller, Ian, Patterson, Joseph, Richmond, Michael, Ringwald, Frederick, Roberts, George, Ruiz, Javier, Sabo, Richard, Stein, William, Shears, Jeremy, Campbell, Tut, Foote, Jerry, Garrett, Russ, Hager, Tim, Julian, William Mack, Kemp, Jonathan, Masi, Gianluca, Miller, Ian, Patterson, Joseph, Richmond, Michael, Ringwald, Frederick, Roberts, George, Ruiz, Javier, Sabo, Richard, and Stein, William
Abstract: During July 2009 we observed the first confirmed superoutburst of the eclipsing dwarf nova SDSS J150240.98+333423.9 using CCD photometry. The outburst amplitude was at least 3.9 magnitudes and it lasted at least 16 days. Superhumps having up to 0.35 peak-to-peak amplitude were present during the outburst, thereby establishing it to be a member of the SU UMa family. The mean superhump period during the first 4 days of the outburst was Psh = 0.06028(19) d, although it increased during the outburst with dPsh/dt = + 2.8(1.0) x 10-4. The orbital period was measured as Porb = 0.05890946(5) d from times of eclipses measured during outburst and quiescence. Based on the mean superhump period, the superhump period excess was 0.023(3). The FWHM eclipse duration declined from a maximum of 10.5 min at the peak of the outburst to 3.5 min later in the outburst. The eclipse depth increased from ~0.9 mag to 2.1 mag over the same period. Eclipses in quiescence were 2.7 min in duration and 2.8 mag deep., Comment: 26 pages, 10 figures. Accepted for publication in JBAA
Published: 2010

34. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae. II: The Second Year (2009-2010)

Author: Kato, Taichi, Maehara, Hiroyuki, Uemura, Makoto, Henden, Arne, de Miguel, Enrique, Miller, Ian, Dubovsky, Pavol A., Kudzej, Igor, Kiyota, Seiichiro, Hambsch, Franz-Josef, Tanabe, Kenji, Imamura, Kazuyoshi, Kunitomi, Nanae, Takagi, Ryosuke, Nose, Mikiha, Akazawa, Hidehiko, Masi, Gianluca, Nakagawa, Shinichi, Iino, Eriko, Noguchi, Ryo, Matsumoto, Katsura, Fujii, Daichi, Kobayashi, Hiroshi, Ogura, Kazuyuki, Ohtomo, Sachi, Yamashita, Kousei, Yanagisawa, Hirofumi, Itoh, Hiroshi, Bolt, Greg, Monard, Berto, Ohshima, Tomohito, Shears, Jeremy, Ruiz, Javier, Imada, Akira, Oksanen, Arto, Nelson, Peter, Gomez, Tomas L., Staels, Bart, Boyd, David, Voloshina, Irina B., Krajci, Thomas, Crawford, Tim, Stockdale, Chris, Richmond, Michael, Morelle, Etienne, Novak, Rudolf, Nogami, Daisaku, Ishioka, Ryoko, Brady, Steve, Simonsen, Mike, Pavlenko, Elena P., Ringwald, Frederick A., Kuramoto, Tetsuya, Miyashita, Atsushi, Pickard, Roger D., Hynek, Tomas, Dvorak, Shawn, Stubbings, Rod, Muyllaert, Eddy, Kato, Taichi, Maehara, Hiroyuki, Uemura, Makoto, Henden, Arne, de Miguel, Enrique, Miller, Ian, Dubovsky, Pavol A., Kudzej, Igor, Kiyota, Seiichiro, Hambsch, Franz-Josef, Tanabe, Kenji, Imamura, Kazuyoshi, Kunitomi, Nanae, Takagi, Ryosuke, Nose, Mikiha, Akazawa, Hidehiko, Masi, Gianluca, Nakagawa, Shinichi, Iino, Eriko, Noguchi, Ryo, Matsumoto, Katsura, Fujii, Daichi, Kobayashi, Hiroshi, Ogura, Kazuyuki, Ohtomo, Sachi, Yamashita, Kousei, Yanagisawa, Hirofumi, Itoh, Hiroshi, Bolt, Greg, Monard, Berto, Ohshima, Tomohito, Shears, Jeremy, Ruiz, Javier, Imada, Akira, Oksanen, Arto, Nelson, Peter, Gomez, Tomas L., Staels, Bart, Boyd, David, Voloshina, Irina B., Krajci, Thomas, Crawford, Tim, Stockdale, Chris, Richmond, Michael, Morelle, Etienne, Novak, Rudolf, Nogami, Daisaku, Ishioka, Ryoko, Brady, Steve, Simonsen, Mike, Pavlenko, Elena P., Ringwald, Frederick A., Kuramoto, Tetsuya, Miyashita, Atsushi, Pickard, Roger D., Hynek, Tomas, Dvorak, Shawn, Stubbings, Rod, and Muyllaert, Eddy
Abstract: As an extension of the project in Kato et al. (2009, arXiv:0905.1757), we collected times of superhump maxima for 61 SU UMa-type dwarf novae mainly observed during the 2009-2010 season. The newly obtained data confirmed the basic findings reported in Kato et al. (2009): the presence of stages A-C, as well as the predominance of positive period derivatives during stage B in systems with superhump periods shorter than 0.07 d. There was a systematic difference in period derivatives for systems with superhump periods longer than 0.075 d between this study and Kato et al. (2009). We suggest that this difference is possibly caused by the relative lack of frequently outbursting SU UMa-type dwarf novae in this period regime in the present study. We recorded a strong beat phenomenon during the 2009 superoutburst of IY UMa. The close correlation between the beat period and superhump period suggests that the changing angular velocity of the apsidal motion of the elliptical disk is responsible for the variation of superhump periods. We also described three new WZ Sge-type objects with established early superhumps and one with likely early superhumps. We also suggest that two systems, VX For and EL UMa, are WZ Sge-type dwarf novae with multiple rebrightenings. The O-C variation in OT J213806.6+261957 suggests that the frequent absence of rebrightenings in very short-Porb objects can be a result of sustained superoutburst plateau at the epoch when usual SU UMa-type dwarf novae return to quiescence preceding a rebrightening. We also present a formulation for a variety of Bayesian extension to traditional period analyses., Comment: 63 pages, 77 figures, 1 appendix, Accepted for publication in PASJ, data correction
Published: 2010
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35. The orbital and superhump periods of the deeply eclipsing dwarf nova SDSS J150240.98+333423.9

Author: Shears, Jeremy, Campbell, Tut, Foote, Jerry, Garrett, Russ, Hager, Tim, Julian, William Mack, Kemp, Jonathan, Masi, Gianluca, Miller, Ian, Patterson, Joseph, Richmond, Michael, Ringwald, Frederick, Roberts, George, Ruiz, Javier, Sabo, Richard, Stein, William, Shears, Jeremy, Campbell, Tut, Foote, Jerry, Garrett, Russ, Hager, Tim, Julian, William Mack, Kemp, Jonathan, Masi, Gianluca, Miller, Ian, Patterson, Joseph, Richmond, Michael, Ringwald, Frederick, Roberts, George, Ruiz, Javier, Sabo, Richard, and Stein, William
Abstract: During July 2009 we observed the first confirmed superoutburst of the eclipsing dwarf nova SDSS J150240.98+333423.9 using CCD photometry. The outburst amplitude was at least 3.9 magnitudes and it lasted at least 16 days. Superhumps having up to 0.35 peak-to-peak amplitude were present during the outburst, thereby establishing it to be a member of the SU UMa family. The mean superhump period during the first 4 days of the outburst was Psh = 0.06028(19) d, although it increased during the outburst with dPsh/dt = + 2.8(1.0) x 10-4. The orbital period was measured as Porb = 0.05890946(5) d from times of eclipses measured during outburst and quiescence. Based on the mean superhump period, the superhump period excess was 0.023(3). The FWHM eclipse duration declined from a maximum of 10.5 min at the peak of the outburst to 3.5 min later in the outburst. The eclipse depth increased from ~0.9 mag to 2.1 mag over the same period. Eclipses in quiescence were 2.7 min in duration and 2.8 mag deep., Comment: 26 pages, 10 figures. Accepted for publication in JBAA
Published: 2010

36. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae

Author: Kato, Taichi, Imada, Akira, Uemura, Makoto, Nogami, Daisaku, Maehara, Hiroyuki, Ishioka, Ryoko, Baba, Hajime, Matsumoto, Katsura, Iwamatsu, Hidetoshi, Kubota, Kaori, Sugiyasu, Kei, Soejima, Yuichi, Moritani, Yuuki, Ohshima, Tomohito, Ohashi, Hiroyuki, Tanaka, Junpei, Sasada, Mahito, Arai, Akira, Nakajima, Kazuhiro, Kiyota, Seiichiro, Tanabe, Kenji, Imamura, Kayuyoshi, Kunitomi, Nanae, Kunihiro, Kenji, Taguchi, Hiroki, Koizumi, Mitsuo, Yamada, Norimi, Nishi, Yuichi, Kida, Mayumi, Tanaka, Sawa, Ueoka, Rie, Yasui, Hideki, Maruoka, Koichi, Henden, Arne, Oksanen, Arto, Moilanen, Marko, Tikkanen, Petri, Aho, Mika, Monard, Berto, Itoh, Hiroshi, Dubovsky, Pavol A., Kudzej, Igor, Dancikova, Radka, Vanmunster, Tonny, Pietz, Jochen, Bolt, Greg, Boyd, David, Nelson, Peter, Krajci, Thomas, Cook, Lewis M., Torii, Ken'ichi, Starkey, Donn R., Shears, Jeremy, Jensen, Lasse-Teist, Masi, Gianluca, Novak, Rudolf, Hynek, Tomas, Kocian, Radek, Kral, Lukas, Kucakova, Hana, Kolasa, Marek, Stastny, Petr, Staels, Bart, Kato, Taichi, Imada, Akira, Uemura, Makoto, Nogami, Daisaku, Maehara, Hiroyuki, Ishioka, Ryoko, Baba, Hajime, Matsumoto, Katsura, Iwamatsu, Hidetoshi, Kubota, Kaori, Sugiyasu, Kei, Soejima, Yuichi, Moritani, Yuuki, Ohshima, Tomohito, Ohashi, Hiroyuki, Tanaka, Junpei, Sasada, Mahito, Arai, Akira, Nakajima, Kazuhiro, Kiyota, Seiichiro, Tanabe, Kenji, Imamura, Kayuyoshi, Kunitomi, Nanae, Kunihiro, Kenji, Taguchi, Hiroki, Koizumi, Mitsuo, Yamada, Norimi, Nishi, Yuichi, Kida, Mayumi, Tanaka, Sawa, Ueoka, Rie, Yasui, Hideki, Maruoka, Koichi, Henden, Arne, Oksanen, Arto, Moilanen, Marko, Tikkanen, Petri, Aho, Mika, Monard, Berto, Itoh, Hiroshi, Dubovsky, Pavol A., Kudzej, Igor, Dancikova, Radka, Vanmunster, Tonny, Pietz, Jochen, Bolt, Greg, Boyd, David, Nelson, Peter, Krajci, Thomas, Cook, Lewis M., Torii, Ken'ichi, Starkey, Donn R., Shears, Jeremy, Jensen, Lasse-Teist, Masi, Gianluca, Novak, Rudolf, Hynek, Tomas, Kocian, Radek, Kral, Lukas, Kucakova, Hana, Kolasa, Marek, Stastny, Petr, and Staels, Bart
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 superhump period are found to be composed of three distinct stages: early evolutionary stage with a longer superhump period, middle stage with systematically varying periods, final stage with a shorter, stable superhump period. During the middle stage, many systems with superhump periods less than 0.08 d show positive period derivatives. Contrary to the earlier claim, we found no clear evidence for variation of period derivatives between superoutburst of the same object. We present an interpretation that the lengthening of the superhump period is a result of outward propagation of the eccentricity wave and is limited by the radius near the tidal truncation. We interpret that late stage superhumps are rejuvenized excitation of 3:1 resonance when the superhumps in the outer disk is effectively quenched. Many of WZ Sge-type dwarf novae showed long-enduring superhumps during the post-superoutburst stage having periods longer 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, 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 candidate for the systems around or after the period minimum of evolution of cataclysmic variables (abridged)., Comment: 239 pages, 225 figures, PASJ accepted
Published: 2009
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37. Photometry of Three Superoutbursts of the SU UMa-type Dwarf Nova, SW Ursae Majoris

Author: Soejima, Yuichi, Nogami, Daisaku, Kato, Taichi, Uemura, Makoto, Imada, Akira, Sugiyasu, Kei, Maehara, Hiroyuki, Torii, Ken'ichi, Tanabe, Kenji, Oksanen, Arto, Nakajima, Kazuhiro, Novak, Rudolf, Masi, Gianluca, Hynek, Tomas, Martin, Brian, Buczynski, Denis, Pavlenko, Elena P., Shugarov, Sergei Yu., Cook, Lewis M., Soejima, Yuichi, Nogami, Daisaku, Kato, Taichi, Uemura, Makoto, Imada, Akira, Sugiyasu, Kei, Maehara, Hiroyuki, Torii, Ken'ichi, Tanabe, Kenji, Oksanen, Arto, Nakajima, Kazuhiro, Novak, Rudolf, Masi, Gianluca, Hynek, Tomas, Martin, Brian, Buczynski, Denis, Pavlenko, Elena P., Shugarov, Sergei Yu., and Cook, Lewis M.
Abstract: We investigated the superhump evolution, analysing optical photometric observations of the 2000 February-March, the 2002 October-November, and the 2006 September superoutbursts of SW UMa. The superhumps evolved in the same way after their appearance during the 2000 and the 2002 superoutbursts, and probably during the 2006 one. This indicates that the superhump evolution may be governed by the invariable binary parameters. We detected a periodicity in light curve after the end of the 2000 superoutburst without phase shift, which seems to be the remains of the superhumps. We found QPOs at the end stage of the 2000 and the 2002 superoutbursts, but failed to find extraordinarily large-amplitude QPOs called `super-QPOs' which previously have been observed in SW UMa., Comment: 17 pages, 19 figures
Published: 2009
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38. Photometry of Three Superoutbursts of the SU UMa-type Dwarf Nova, SW Ursae Majoris

Author: Soejima, Yuichi, Nogami, Daisaku, Kato, Taichi, Uemura, Makoto, Imada, Akira, Sugiyasu, Kei, Maehara, Hiroyuki, Torii, Ken'ichi, Tanabe, Kenji, Oksanen, Arto, Nakajima, Kazuhiro, Novak, Rudolf, Masi, Gianluca, Hynek, Tomas, Martin, Brian, Buczynski, Denis, Pavlenko, Elena P., Shugarov, Sergei Yu., Cook, Lewis M., Soejima, Yuichi, Nogami, Daisaku, Kato, Taichi, Uemura, Makoto, Imada, Akira, Sugiyasu, Kei, Maehara, Hiroyuki, Torii, Ken'ichi, Tanabe, Kenji, Oksanen, Arto, Nakajima, Kazuhiro, Novak, Rudolf, Masi, Gianluca, Hynek, Tomas, Martin, Brian, Buczynski, Denis, Pavlenko, Elena P., Shugarov, Sergei Yu., and Cook, Lewis M.
Abstract: We investigated the superhump evolution, analysing optical photometric observations of the 2000 February-March, the 2002 October-November, and the 2006 September superoutbursts of SW UMa. The superhumps evolved in the same way after their appearance during the 2000 and the 2002 superoutbursts, and probably during the 2006 one. This indicates that the superhump evolution may be governed by the invariable binary parameters. We detected a periodicity in light curve after the end of the 2000 superoutburst without phase shift, which seems to be the remains of the superhumps. We found QPOs at the end stage of the 2000 and the 2002 superoutbursts, but failed to find extraordinarily large-amplitude QPOs called `super-QPOs' which previously have been observed in SW UMa., Comment: 17 pages, 19 figures
Published: 2009
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39. Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae

Author: Kato, Taichi, Imada, Akira, Uemura, Makoto, Nogami, Daisaku, Maehara, Hiroyuki, Ishioka, Ryoko, Baba, Hajime, Matsumoto, Katsura, Iwamatsu, Hidetoshi, Kubota, Kaori, Sugiyasu, Kei, Soejima, Yuichi, Moritani, Yuuki, Ohshima, Tomohito, Ohashi, Hiroyuki, Tanaka, Junpei, Sasada, Mahito, Arai, Akira, Nakajima, Kazuhiro, Kiyota, Seiichiro, Tanabe, Kenji, Imamura, Kayuyoshi, Kunitomi, Nanae, Kunihiro, Kenji, Taguchi, Hiroki, Koizumi, Mitsuo, Yamada, Norimi, Nishi, Yuichi, Kida, Mayumi, Tanaka, Sawa, Ueoka, Rie, Yasui, Hideki, Maruoka, Koichi, Henden, Arne, Oksanen, Arto, Moilanen, Marko, Tikkanen, Petri, Aho, Mika, Monard, Berto, Itoh, Hiroshi, Dubovsky, Pavol A., Kudzej, Igor, Dancikova, Radka, Vanmunster, Tonny, Pietz, Jochen, Bolt, Greg, Boyd, David, Nelson, Peter, Krajci, Thomas, Cook, Lewis M., Torii, Ken'ichi, Starkey, Donn R., Shears, Jeremy, Jensen, Lasse-Teist, Masi, Gianluca, Novak, Rudolf, Hynek, Tomas, Kocian, Radek, Kral, Lukas, Kucakova, Hana, Kolasa, Marek, Stastny, Petr, Staels, Bart, Kato, Taichi, Imada, Akira, Uemura, Makoto, Nogami, Daisaku, Maehara, Hiroyuki, Ishioka, Ryoko, Baba, Hajime, Matsumoto, Katsura, Iwamatsu, Hidetoshi, Kubota, Kaori, Sugiyasu, Kei, Soejima, Yuichi, Moritani, Yuuki, Ohshima, Tomohito, Ohashi, Hiroyuki, Tanaka, Junpei, Sasada, Mahito, Arai, Akira, Nakajima, Kazuhiro, Kiyota, Seiichiro, Tanabe, Kenji, Imamura, Kayuyoshi, Kunitomi, Nanae, Kunihiro, Kenji, Taguchi, Hiroki, Koizumi, Mitsuo, Yamada, Norimi, Nishi, Yuichi, Kida, Mayumi, Tanaka, Sawa, Ueoka, Rie, Yasui, Hideki, Maruoka, Koichi, Henden, Arne, Oksanen, Arto, Moilanen, Marko, Tikkanen, Petri, Aho, Mika, Monard, Berto, Itoh, Hiroshi, Dubovsky, Pavol A., Kudzej, Igor, Dancikova, Radka, Vanmunster, Tonny, Pietz, Jochen, Bolt, Greg, Boyd, David, Nelson, Peter, Krajci, Thomas, Cook, Lewis M., Torii, Ken'ichi, Starkey, Donn R., Shears, Jeremy, Jensen, Lasse-Teist, Masi, Gianluca, Novak, Rudolf, Hynek, Tomas, Kocian, Radek, Kral, Lukas, Kucakova, Hana, Kolasa, Marek, Stastny, Petr, and Staels, Bart
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 superhump period are found to be composed of three distinct stages: early evolutionary stage with a longer superhump period, middle stage with systematically varying periods, final stage with a shorter, stable superhump period. During the middle stage, many systems with superhump periods less than 0.08 d show positive period derivatives. Contrary to the earlier claim, we found no clear evidence for variation of period derivatives between superoutburst of the same object. We present an interpretation that the lengthening of the superhump period is a result of outward propagation of the eccentricity wave and is limited by the radius near the tidal truncation. We interpret that late stage superhumps are rejuvenized excitation of 3:1 resonance when the superhumps in the outer disk is effectively quenched. Many of WZ Sge-type dwarf novae showed long-enduring superhumps during the post-superoutburst stage having periods longer 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, 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 candidate for the systems around or after the period minimum of evolution of cataclysmic variables (abridged)., Comment: 239 pages, 225 figures, PASJ accepted
Published: 2009
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40. The 2006 November outburst of EG Aquarii: the SU UMa nature revealed

Author: Imada, Akira, Stubbings, Rod, Kato, Taichi, Uemura, Makoto, Krajci, Thomas, Torii, Ken'ichi, Sugiyasu, Kei, Kubota, Kaori, Moritani, Yuuki, Ishioka, Ryoko, Masi, Gianluca, Kiyota, Seiichiro, Monard, L. A. G., Maehara, Hiroyuki, Nakajima, Kazuhiro, Arai, Akira, Ohsugi, Takashi, Yamashita, Takuya, Kawabata, Koji S., Nagae, Osamu, Chiyonobu, Shingo, Fukazawa, Yasushi, Mizuno, Tsunefumi, Katagiri, Hideaki, Takahashi, Hiromitsu, Ueda, Atsushi, Hayashi, Takehiro, Okita, Kiichi, Yoshida, Michitoshi, Yanagisawa, Kenshi, Sato, Shuji, Kino, Masaru, Kitagawa, Masahiro, Sadakane, Kozo, Nogami, Daisaku, Imada, Akira, Stubbings, Rod, Kato, Taichi, Uemura, Makoto, Krajci, Thomas, Torii, Ken'ichi, Sugiyasu, Kei, Kubota, Kaori, Moritani, Yuuki, Ishioka, Ryoko, Masi, Gianluca, Kiyota, Seiichiro, Monard, L. A. G., Maehara, Hiroyuki, Nakajima, Kazuhiro, Arai, Akira, Ohsugi, Takashi, Yamashita, Takuya, Kawabata, Koji S., Nagae, Osamu, Chiyonobu, Shingo, Fukazawa, Yasushi, Mizuno, Tsunefumi, Katagiri, Hideaki, Takahashi, Hiromitsu, Ueda, Atsushi, Hayashi, Takehiro, Okita, Kiichi, Yoshida, Michitoshi, Yanagisawa, Kenshi, Sato, Shuji, Kino, Masaru, Kitagawa, Masahiro, Sadakane, Kozo, and Nogami, Daisaku
Abstract: We report time-resolved CCD photometry of the cataclysmic variable EG Aquarii during the 2006 November outburst During the outburst, superhumps were unambiguously detected with a mean period of 0.078828(6) days, firstly classifying the object as an SU UMa-type dwarf nova. It also turned out that the outburst contained a precursor. At the end of the precursor, immature profiles of humps were observed. By a phase analysis of these humps, we interpreted the features as superhumps. This is the second example that the superhumps were shown during a precursor. Near the maximum stage of the outburst, we discovered an abrupt shift of the superhump period by ${\sim}$ 0.002 days. After the supermaximum, the superhump period decreased at the rate of $\dot{P}/P$=$-8.2{\times}10^{-5}$, which is typical for SU UMa-type dwarf novae. Although the outburst light curve was characteristic of SU UMa-type dwarf novae, long-term monitoring of the variable shows no outbursts over the past decade. We note on the basic properties of long period and inactive SU UMa-type dwarf novae., Comment: 9 pages, 7 figures, accepted for PASJ
Published: 2008
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41. The 2006 November outburst of EG Aquarii: the SU UMa nature revealed

Author: Imada, Akira, Stubbings, Rod, Kato, Taichi, Uemura, Makoto, Krajci, Thomas, Torii, Ken'ichi, Sugiyasu, Kei, Kubota, Kaori, Moritani, Yuuki, Ishioka, Ryoko, Masi, Gianluca, Kiyota, Seiichiro, Monard, L. A. G., Maehara, Hiroyuki, Nakajima, Kazuhiro, Arai, Akira, Ohsugi, Takashi, Yamashita, Takuya, Kawabata, Koji S., Nagae, Osamu, Chiyonobu, Shingo, Fukazawa, Yasushi, Mizuno, Tsunefumi, Katagiri, Hideaki, Takahashi, Hiromitsu, Ueda, Atsushi, Hayashi, Takehiro, Okita, Kiichi, Yoshida, Michitoshi, Yanagisawa, Kenshi, Sato, Shuji, Kino, Masaru, Kitagawa, Masahiro, Sadakane, Kozo, Nogami, Daisaku, Imada, Akira, Stubbings, Rod, Kato, Taichi, Uemura, Makoto, Krajci, Thomas, Torii, Ken'ichi, Sugiyasu, Kei, Kubota, Kaori, Moritani, Yuuki, Ishioka, Ryoko, Masi, Gianluca, Kiyota, Seiichiro, Monard, L. A. G., Maehara, Hiroyuki, Nakajima, Kazuhiro, Arai, Akira, Ohsugi, Takashi, Yamashita, Takuya, Kawabata, Koji S., Nagae, Osamu, Chiyonobu, Shingo, Fukazawa, Yasushi, Mizuno, Tsunefumi, Katagiri, Hideaki, Takahashi, Hiromitsu, Ueda, Atsushi, Hayashi, Takehiro, Okita, Kiichi, Yoshida, Michitoshi, Yanagisawa, Kenshi, Sato, Shuji, Kino, Masaru, Kitagawa, Masahiro, Sadakane, Kozo, and Nogami, Daisaku
Abstract: We report time-resolved CCD photometry of the cataclysmic variable EG Aquarii during the 2006 November outburst During the outburst, superhumps were unambiguously detected with a mean period of 0.078828(6) days, firstly classifying the object as an SU UMa-type dwarf nova. It also turned out that the outburst contained a precursor. At the end of the precursor, immature profiles of humps were observed. By a phase analysis of these humps, we interpreted the features as superhumps. This is the second example that the superhumps were shown during a precursor. Near the maximum stage of the outburst, we discovered an abrupt shift of the superhump period by ${\sim}$ 0.002 days. After the supermaximum, the superhump period decreased at the rate of $\dot{P}/P$=$-8.2{\times}10^{-5}$, which is typical for SU UMa-type dwarf novae. Although the outburst light curve was characteristic of SU UMa-type dwarf novae, long-term monitoring of the variable shows no outbursts over the past decade. We note on the basic properties of long period and inactive SU UMa-type dwarf novae., Comment: 9 pages, 7 figures, accepted for PASJ
Published: 2008
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42. Superhumps in Cataclysmic Binaries. XXV. q_crit, epsilon(q), and Mass-Radius

Author: Patterson, Joseph, Kemp, Jonathan, Harvey, David, Fried, Robert, Rea, Robert, Monard, Berto, Cook, Lewis, Skillman, David, Vanmunster, Tonny, Bolt, Greg, Armstrong, Eve, McCormick, Jennie, Krajci, Thomas, Jensen, Lasse, Gunn, Jerry, Butterworth, Neil, Foote, Jerry, Bos, Marc, Masi, Gianluca, Warhurst, Paul, Patterson, Joseph, Kemp, Jonathan, Harvey, David, Fried, Robert, Rea, Robert, Monard, Berto, Cook, Lewis, Skillman, David, Vanmunster, Tonny, Bolt, Greg, Armstrong, Eve, McCormick, Jennie, Krajci, Thomas, Jensen, Lasse, Gunn, Jerry, Butterworth, Neil, Foote, Jerry, Bos, Marc, Masi, Gianluca, and Warhurst, Paul
Abstract: We report on successes and failures in searching for positive superhumps in cataclysmic variables, and show the superhumping fraction as a function of orbital period. Basically, all short-period systems do, all long-period systems don't, and a 50% success rate is found at P_orb=3.1+-0.2 hr. We can use this to measure the critical mass ratio for the creation of superhumps. With a mass-radius relation appropriate for cataclysmic variables, and an assumed mean white-dwarf mass of 0.75 M_sol, we find a mass ratio q_crit=0.35+-0.02. We also report superhump studies of several stars of independently known mass ratio: OU Virginis, XZ Eridani, UU Aquarii, and KV UMa (= XTE J1118+480). The latter two are of special interest, because they represent the most extreme mass ratios for which accurate superhump measurements have been made. We use these to improve the epsilon(q) calibration, by which we can infer the elusive q from the easy-to-measure epsilon (the fractional period excess of P_superhump over P_orb). This relation allows mass and radius estimates for the secondary star in any CV showing superhumps. The consequent mass-radius law shows an apparent discontinuity in radius near 0.2 M_sol, as predicted by the disrupted magnetic braking model for the 2.1-2.7 hour period gap. This is effectively the "empirical main sequence" for CV secondaries., Comment: PDF, 45 pages, 9 tables, 12 figures; accepted, in press, to appear November 2005, PASP; more info at http://cba.phys.columbia.edu
Published: 2005
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43. Superhumps in Cataclysmic Binaries. XXV. q_crit, epsilon(q), and Mass-Radius

Author: Patterson, Joseph, Kemp, Jonathan, Harvey, David, Fried, Robert, Rea, Robert, Monard, Berto, Cook, Lewis, Skillman, David, Vanmunster, Tonny, Bolt, Greg, Armstrong, Eve, McCormick, Jennie, Krajci, Thomas, Jensen, Lasse, Gunn, Jerry, Butterworth, Neil, Foote, Jerry, Bos, Marc, Masi, Gianluca, Warhurst, Paul, Patterson, Joseph, Kemp, Jonathan, Harvey, David, Fried, Robert, Rea, Robert, Monard, Berto, Cook, Lewis, Skillman, David, Vanmunster, Tonny, Bolt, Greg, Armstrong, Eve, McCormick, Jennie, Krajci, Thomas, Jensen, Lasse, Gunn, Jerry, Butterworth, Neil, Foote, Jerry, Bos, Marc, Masi, Gianluca, and Warhurst, Paul
Abstract: We report on successes and failures in searching for positive superhumps in cataclysmic variables, and show the superhumping fraction as a function of orbital period. Basically, all short-period systems do, all long-period systems don't, and a 50% success rate is found at P_orb=3.1+-0.2 hr. We can use this to measure the critical mass ratio for the creation of superhumps. With a mass-radius relation appropriate for cataclysmic variables, and an assumed mean white-dwarf mass of 0.75 M_sol, we find a mass ratio q_crit=0.35+-0.02. We also report superhump studies of several stars of independently known mass ratio: OU Virginis, XZ Eridani, UU Aquarii, and KV UMa (= XTE J1118+480). The latter two are of special interest, because they represent the most extreme mass ratios for which accurate superhump measurements have been made. We use these to improve the epsilon(q) calibration, by which we can infer the elusive q from the easy-to-measure epsilon (the fractional period excess of P_superhump over P_orb). This relation allows mass and radius estimates for the secondary star in any CV showing superhumps. The consequent mass-radius law shows an apparent discontinuity in radius near 0.2 M_sol, as predicted by the disrupted magnetic braking model for the 2.1-2.7 hour period gap. This is effectively the "empirical main sequence" for CV secondaries., Comment: PDF, 45 pages, 9 tables, 12 figures; accepted, in press, to appear November 2005, PASP; more info at http://cba.phys.columbia.edu
Published: 2005
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44. Outburst and Post-Outburst Active Phase of the Black Hole X-Ray Binary V4641 Sagittarii in 2002

Author: Uemura, Makoto, Kato, Taichi, Ishioka, Ryoko, Tanabe, Kenji, Torii, Ken, Santallo, Roland, Monard, Berto, Markwardt, Craig, Swank, Jean, Sault, Robert, Macquart, Jean-Pierre, Linnolt, Michael, Kiyoto, Seiichiro, Stubbings, Rod, Nelson, Peter, Richards, Tom, Bailyn, Charles, West, Doug, Masi, Gianluca, Miyashita, Atsushi, Sano, Yasuo, Scarmato, Toni, Uemura, Makoto, Kato, Taichi, Ishioka, Ryoko, Tanabe, Kenji, Torii, Ken, Santallo, Roland, Monard, Berto, Markwardt, Craig, Swank, Jean, Sault, Robert, Macquart, Jean-Pierre, Linnolt, Michael, Kiyoto, Seiichiro, Stubbings, Rod, Nelson, Peter, Richards, Tom, Bailyn, Charles, West, Doug, Masi, Gianluca, Miyashita, Atsushi, Sano, Yasuo, and Scarmato, Toni
Abstract: The black hole X-ray binary V4641 Sgr experienced an outburst in 2002 May, which was detected at X-ray, optical, and radio wavelengths. The outburst lasted for only 6 days, but the object remained active for the next several months. Here, we report on the detailed properties of light curves during the outburst and the post-outburst active phase. We reveal that rapid optical variations of -100s became more prominent when a thermal flare weakened and the optical spectrum flattened in the Ic, Rc, and V-band regions. In conjunction with the flat spectrum in the radio range, this strongly indicates that the origin of rapid variations is not thermal emission, but synchrotron emission. Just after the outburst, we detected repeated flares at optical and X-ray wavelengths. The optical and X-ray light curves exhibited a strong correlation with the X-rays lagging by about 7min. The X-ray lag can be understood in terms of a hot region propagating into the inner region of the accretion flow. The short X-ray lag, however, requires modifications of this simple scenario to account for the short propagation time. We also detected high-amplitude rapid variations 50 days after the outburst, which we call optical flashes. During the most prominent optical flash, the object brightened by 1.2mag only within 30s. The released energy indicates that the emission source should be at the innermost region of the accretion flow. (author abst.)
Published: 2003

45. First detection of the growing humps at the rapidly rising stage of dwarf novae AL Com and WZ Sge

Author: Ishioka, Ryoko, Uemura, Makoto, Matsumoto, Katsura, Ohashi, Hiroyuki, Kato, Taichi, Masi, Gianluca, Novak, Rudolf, Pietz, Jochen, Martin, Brian, Starkey, Donn, Kiyota, Seiichiro, Oksanen, Arto, Moilanen, Marko, Cook, Lew, Ishioka, Ryoko, Uemura, Makoto, Matsumoto, Katsura, Ohashi, Hiroyuki, Kato, Taichi, Masi, Gianluca, Novak, Rudolf, Pietz, Jochen, Martin, Brian, Starkey, Donn, Kiyota, Seiichiro, Oksanen, Arto, Moilanen, Marko, and Cook, Lew
Abstract: We report on time-series photometric observations in the earliest stages of superoutbursts of the extreme dwarf novae, AL Com and WZ Sge, which started on 2001 May after the 6 years quiescence and on 2001 July after the 23 years quiescence, respectively. We detected growth of ``early superhumps'' during the each rising stage. Our observations reject the mass transfer instability for the trigger of the superoutburst of WZ Sge stars, and show the existence of some relations between the ``early superhumps'' and the spiral structure, which give a hint of the origin of the ``early superhumps.'', Comment: 4 pages, 4 figures, A&A macro in latex format, accepted to A&A letters
Published: 2001
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46. First detection of the growing humps at the rapidly rising stage of dwarf novae AL Com and WZ Sge

Author: Ishioka, Ryoko, Uemura, Makoto, Matsumoto, Katsura, Ohashi, Hiroyuki, Kato, Taichi, Masi, Gianluca, Novak, Rudolf, Pietz, Jochen, Martin, Brian, Starkey, Donn, Kiyota, Seiichiro, Oksanen, Arto, Moilanen, Marko, Cook, Lew, Ishioka, Ryoko, Uemura, Makoto, Matsumoto, Katsura, Ohashi, Hiroyuki, Kato, Taichi, Masi, Gianluca, Novak, Rudolf, Pietz, Jochen, Martin, Brian, Starkey, Donn, Kiyota, Seiichiro, Oksanen, Arto, Moilanen, Marko, and Cook, Lew
Abstract: We report on time-series photometric observations in the earliest stages of superoutbursts of the extreme dwarf novae, AL Com and WZ Sge, which started on 2001 May after the 6 years quiescence and on 2001 July after the 23 years quiescence, respectively. We detected growth of ``early superhumps'' during the each rising stage. Our observations reject the mass transfer instability for the trigger of the superoutburst of WZ Sge stars, and show the existence of some relations between the ``early superhumps'' and the spiral structure, which give a hint of the origin of the ``early superhumps.'', Comment: 4 pages, 4 figures, A&A macro in latex format, accepted to A&A letters
Published: 2001
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47. Molecular and pathological characterization of the EZH2 rs3757441 single nucleotide polymorphism in colorectal cancer

Author: Fornaro, Lorenzo, Faviana, Pinuccia, De Gregorio, Veronica, Vivaldi, Caterina, Paolicchi, Elisa, Masi, Gianluca, Loupakis, Fotios, Sensi, Elisa, Lupi, Cristiana, Fontanini, Garbriella, Wang, Yuzhuo, Danesi, Romano, Falcone, Alfredo, Crea, Francesco, Fornaro, Lorenzo, Faviana, Pinuccia, De Gregorio, Veronica, Vivaldi, Caterina, Paolicchi, Elisa, Masi, Gianluca, Loupakis, Fotios, Sensi, Elisa, Lupi, Cristiana, Fontanini, Garbriella, Wang, Yuzhuo, Danesi, Romano, Falcone, Alfredo, and Crea, Francesco
Abstract: Background The enhancer of zeste-homolog 2 (EZH2) is involved in cancer development through gene silencing by trimethylation of lysine 27 of histone 3 (H3K27me3). The C/C genotype for the EZH2 rs3757441 single-nucleotide polymorphism (SNP) is linked with poor prognosis in metastatic colorectal cancer (CRC), but molecular and pathological characterization of this SNP is lacking. Methods 119 primary CRCs were analyzed. SNP was evaluated by real-time PCR from colonic healthy tissue, while EZH2 and H3K27me3 expression were studied by immunohistochemistry. We primarily looked for correlation between EZH2 rs3757441 genotypes and EZH2/H3K27me3 expression. Potential associations between EZH2/H3K27me3 expression and clinico-pathological features or KRAS exon 2 and BRAF exon 15 mutations were secondary endpoints. Statistical analysis was performed by chi-square test, T-test or ANOVA. Results The C/C genotype was significantly associated with higher EZH2 (100 vs. 44 %; P = 0.019) and H3K27me3 (100 vs. 38 %; P = 0.009) staining intensity compared with C/T and T/T. EZH2 3+ staining significantly correlated with stronger H3K27me3 expression (P = 0.039). KRAS and BRAF mutations were not associated with EZH2 or H3K27me3 expression. Conclusion EZH2 rs3757441 C/C genotype is associated with stronger EZH2 and H3K27me3 immunoreactivity in primary CRC: this SNP may serve as a promising biomarker for EZH2-targeting agents and may add independent information to KRAS and BRAF testing.

48. Predictive significance of circulating histones in hepatocellular carcinoma patients treated with sorafenib

Author: Salani, Francesca, Latarani, Maryam, Casadei-Gardini, Andrea, Gangadharannambiar, Priyadarsini, Fornaro, Lorenzo, Vivaldi, Caterina, Pecora, Irene, Massa, Valentina, Marisi, Giorgia, Canale, Matteo, Ulivi, Paola, Scartozzi, Mario, Eccleston, Mark, Masi, Gianluca, Crea, Francesco, Salani, Francesca, Latarani, Maryam, Casadei-Gardini, Andrea, Gangadharannambiar, Priyadarsini, Fornaro, Lorenzo, Vivaldi, Caterina, Pecora, Irene, Massa, Valentina, Marisi, Giorgia, Canale, Matteo, Ulivi, Paola, Scartozzi, Mario, Eccleston, Mark, Masi, Gianluca, and Crea, Francesco
Abstract: Background: Predictive biomarkers for advanced hepatocellular carcinoma are lacking. EZH2 drives sorafenib resistance through H3K27me3 and is counteracted by SETD2, which catalyzes H3K36me3. The authors tested the predictive power of circulating H3K27me3 and H3K36me3 in advanced hepatocellular carcinoma patients treated with sorafenib. Methods: A total of 80 plasma samples were tested for histone variants by ELISA. Changes from baseline to best response or progressive disease were correlated with patient survival. Results: A higher EZH2/SETD2 ratio predicted worse prognosis in this setting. H3K27me3 and H3K36me3 decreased from baseline to best response. The H3K27me3/H3K36me3 ratio increased from baseline to progressive disease. Higher ratios at best response were associated with shorter progression-free survival. Conclusion: The authors suggest that circulating H3K27me3/H3K36me3 ratio level acts as a predictive biomarker for sorafenib treatment outcomes in patients with advanced hepatocellular carcinoma.

49. Molecular and pathological characterization of the EZH2 rs3757441 single nucleotide polymorphism in colorectal cancer

Author: Fornaro, Lorenzo, Faviana, Pinuccia, De Gregorio, Veronica, Vivaldi, Caterina, Paolicchi, Elisa, Masi, Gianluca, Loupakis, Fotios, Sensi, Elisa, Lupi, Cristiana, Fontanini, Garbriella, Wang, Yuzhuo, Danesi, Romano, Falcone, Alfredo, Crea, Francesco, Fornaro, Lorenzo, Faviana, Pinuccia, De Gregorio, Veronica, Vivaldi, Caterina, Paolicchi, Elisa, Masi, Gianluca, Loupakis, Fotios, Sensi, Elisa, Lupi, Cristiana, Fontanini, Garbriella, Wang, Yuzhuo, Danesi, Romano, Falcone, Alfredo, and Crea, Francesco
Abstract: Background The enhancer of zeste-homolog 2 (EZH2) is involved in cancer development through gene silencing by trimethylation of lysine 27 of histone 3 (H3K27me3). The C/C genotype for the EZH2 rs3757441 single-nucleotide polymorphism (SNP) is linked with poor prognosis in metastatic colorectal cancer (CRC), but molecular and pathological characterization of this SNP is lacking. Methods 119 primary CRCs were analyzed. SNP was evaluated by real-time PCR from colonic healthy tissue, while EZH2 and H3K27me3 expression were studied by immunohistochemistry. We primarily looked for correlation between EZH2 rs3757441 genotypes and EZH2/H3K27me3 expression. Potential associations between EZH2/H3K27me3 expression and clinico-pathological features or KRAS exon 2 and BRAF exon 15 mutations were secondary endpoints. Statistical analysis was performed by chi-square test, T-test or ANOVA. Results The C/C genotype was significantly associated with higher EZH2 (100 vs. 44 %; P = 0.019) and H3K27me3 (100 vs. 38 %; P = 0.009) staining intensity compared with C/T and T/T. EZH2 3+ staining significantly correlated with stronger H3K27me3 expression (P = 0.039). KRAS and BRAF mutations were not associated with EZH2 or H3K27me3 expression. Conclusion EZH2 rs3757441 C/C genotype is associated with stronger EZH2 and H3K27me3 immunoreactivity in primary CRC: this SNP may serve as a promising biomarker for EZH2-targeting agents and may add independent information to KRAS and BRAF testing.

50. Predictive significance of circulating histones in hepatocellular carcinoma patients treated with sorafenib

Author: Salani, Francesca, Latarani, Maryam, Casadei-Gardini, Andrea, Gangadharannambiar, Priyadarsini, Fornaro, Lorenzo, Vivaldi, Caterina, Pecora, Irene, Massa, Valentina, Marisi, Giorgia, Canale, Matteo, Ulivi, Paola, Scartozzi, Mario, Eccleston, Mark, Masi, Gianluca, Crea, Francesco, Salani, Francesca, Latarani, Maryam, Casadei-Gardini, Andrea, Gangadharannambiar, Priyadarsini, Fornaro, Lorenzo, Vivaldi, Caterina, Pecora, Irene, Massa, Valentina, Marisi, Giorgia, Canale, Matteo, Ulivi, Paola, Scartozzi, Mario, Eccleston, Mark, Masi, Gianluca, and Crea, Francesco
Abstract: Background: Predictive biomarkers for advanced hepatocellular carcinoma are lacking. EZH2 drives sorafenib resistance through H3K27me3 and is counteracted by SETD2, which catalyzes H3K36me3. The authors tested the predictive power of circulating H3K27me3 and H3K36me3 in advanced hepatocellular carcinoma patients treated with sorafenib. Methods: A total of 80 plasma samples were tested for histone variants by ELISA. Changes from baseline to best response or progressive disease were correlated with patient survival. Results: A higher EZH2/SETD2 ratio predicted worse prognosis in this setting. H3K27me3 and H3K36me3 decreased from baseline to best response. The H3K27me3/H3K36me3 ratio increased from baseline to progressive disease. Higher ratios at best response were associated with shorter progression-free survival. Conclusion: The authors suggest that circulating H3K27me3/H3K36me3 ratio level acts as a predictive biomarker for sorafenib treatment outcomes in patients with advanced hepatocellular carcinoma.

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