Search Results - "Siwak, Michał"

Light curve variation caused by accretion column switching stellar hemispheres by Čemeljić, Miljenko, Siwak, Michał

“…Abstract We investigate switching of the accretion column between the stellar hemispheres in the magnetosphere of a star with the dipole magnetic field aligned…”
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Erratum: “Optical Variability of Eight FRII-type Quasars with 13 yr Photometric Light Curves” (2022, ApJS, 263, 16) by Kuźmicz, Agnieszka, Goyal, Arti, Zola, Stanisław, Jamrozy, Marek, Dróżdż, Marek, Ogłoza, Waldemar, Siwak, Michał, Reichart, Daniel E., Kouprianov, Vladimir V., Caton, Daniel B.

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Recurrent Strong Outbursts of an EXor-like Young Eruptive Star Gaia20eae by Cruz-Sáenz de Miera, Fernando, Kóspál, Ágnes, Ábrahám, Péter, Park, Sunkyung, Nagy, Zsófia, Siwak, Michał, Kun, Mária, Fiorellino, Eleonora, Szabó, Zsófia Marianna, Antoniucci, Simone, Giannini, Teresa, Nisini, Brunella, Szabados, László, Kriskovics, Levente, Ordasi, András, Szakáts, Róbert, Vida, Krisztián, Vinkó, József, Zieliński, Paweł, Wyrzykowski, Łukasz, García-Álvarez, David, Dróżdż, Marek, Ogłoza, Waldemar, Sonbas, Eda

“…Abstract We present follow-up photometric and spectroscopic observations, and subsequent analysis of Gaia20eae. This source triggered photometric alerts during…”
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Gaia21bty: An EXor light curve exhibiting a FUor spectrum by Siwak, Michał, Hillenbrand, Lynne A, Kóspál, Ágnes, Ábrahám, Péter, Giannini, Teresa, De, Kishalay, Moór, Attila, Szilágyi, Máté, Janík, Jan, Koen, Chris, Park, Sunkyung, Nagy, Zsófia, Cruz-Sáenz de Miera, Fernando, Fiorellino, Eleonora, Marton, Gábor, Kun, Mária, Lucas, Philip W, Udalski, Andrzej, Szabó, Zsófia Marianna

“…ABSTRACT Gaia21bty, a pre-main-sequence star that previously had shown aperiodic dips in its light curve, underwent a considerable ΔG ≈ 2.9 mag brightening…”
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Photometric and Spectroscopic Study of the EXor-like Eruptive Young Star Gaia19fct by Park, Sunkyung, Kóspál, Ágnes, Ábrahám, Péter, Cruz-Sáenz de Miera, Fernando, Fiorellino, Eleonora, Siwak, Michał, Nagy, Zsófia, Giannini, Teresa, Carini, Roberta, Szabó, Zsófia Marianna, Lee, Jeong-Eun, Lee, Jae-Joon, Vitali, Fabrizio, Kun, Mária, Cseh, Borbála, Krezinger, Máté, Kriskovics, Levente, Ordasi, András, Pál, András, Szakáts, Róbert, Vida, Krisztián, Vinkó, József

“…Abstract Gaia19fct is one of the Gaia-alerted eruptive young stars that has undergone several brightening events. We conducted monitoring observations using…”
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Optical Variability of Eight FRII-type Quasars with 13 yr Photometric Light Curves by Kuźmicz, Agnieszka, Goyal, Arti, Zola, Stanisław, Jamrozy, Marek, Dróżdż, Marek, Ogłoza, Waldemar, Siwak, Michał, Reichart, Daniel E., Kouprianov, Vladimir V., Caton, Daniel B.

“…Abstract We characterize the optical variability properties of eight lobe-dominated radio quasars (QSOs): B2 0709+37, FBQS J095206.3+235245, PG 1004+130,…”
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V899 Mon: A Peculiar Eruptive Young Star Close to the End of Its Outburst by Park, Sunkyung, Kóspál, Ágnes, Cruz-Sáenz de Miera, Fernando, Siwak, Michał, Dróżdż, Marek, Ignácz, Bernadett, Jaffe, Daniel T., Könyves-Tóth, Réka, Kriskovics, Levente, Lee, Jae-Joon, Lee, Jeong-Eun, Mace, Gregory N., Ogłoza, Waldemar, Pál, András, Potter, Stephen B., Szabó, Zsófia Marianna, Sefako, Ramotholo, Worters, Hannah L.

“…Abstract The eruptive young star V899 Mon shows characteristics of both FUors and EXors. It reached a peak brightness in 2010, then briefly faded in 2011,…”
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The Gaia alerted fading of the FUor-type star Gaia21elv by Nagy, Zsófia, Park, Sunkyung, Ábrahám, Péter, Kóspál, Ágnes, Cruz-Sáenz de Miera, Fernando, Kun, Mária, Siwak, Michał, Szabó, Zsófia Marianna, Szilágyi, Máté, Fiorellino, Eleonora, Giannini, Teresa, Lee, Jae-Joon, Lee, Jeong-Eun, Marton, Gábor, Szabados, László, Vitali, Fabrizio, Andrzejewski, Jan, Gromadzki, Mariusz, Hodgkin, Simon, Jabłońska, Maja, Mendez, Rene A, Merc, Jaroslav, Michniewicz, Olga, Mikołajczyk, Przemysław J, Pylypenko, Uliana, Ratajczak, Milena, Wyrzykowski, Łukasz, Zejmo, Michal, Zieliński, Paweł

“…ABSTRACT FU Orionis objects (FUors) are eruptive young stars, which exhibit outbursts that last from decades to a century. Due to the duration of their…”
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Photometric and spectroscopic study of the burst-like brightening of two Gaia-alerted young stellar objects by Nagy, Zsófia, Ábrahám, Péter, Kóspál, Ágnes, Park, Sunkyung, Siwak, Michał, Cruz-Sáenz de Miera, Fernando, Fiorellino, Eleonora, García-Álvarez, David, Szabó, Zsófia Marianna, Antoniucci, Simone, Giannini, Teresa, Giunta, Alessio, Kriskovics, Levente, Kun, Mária, Marton, Gábor, Moór, Attila, Nisini, Brunella, Pál, Andras, Szabados, László, Zieliński, Paweł, Wyrzykowski, Łukasz

“…ABSTRACT Young stars show variability on different time-scales from hours to decades, with a range of amplitudes. We studied two young stars, which triggered…”
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Analysis of variability of TW Hya as observed by MOST and ASAS in 2009 by Siwak, Michal, Rucinski, Slavek M., Matthews, Jaymie M., Pojmański, Grzegorz, Kuschnig, Rainer, Guenther, David B., Moffat, Anthony F. J., Sasselov, Dimitar, Weiss, Werner W.

“…As a continuation of our previous studies in 2007 and 2008, new photometric observations of the T Tauri star TW Hya obtained by the MOST satellite and the All…”
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A stable quasi-periodic 4.18-d oscillation and mysterious occultations in the 2011 MOST light-curve of TW Hya by Siwak, Michal, Rucinski, Slavek M., Matthews, Jaymie M., Guenther, David B., Kuschnig, Rainer, Moffat, Anthony F. J., Rowe, Jason F., Sasselov, Dimitar, Weiss, Werner W.

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Constraining the degree of the dominant mode in QQ Vir by Baran, Andrzej, Telting, John, Østensen, Roy, Winiarski, Maciej, Drożdż, Marek, Kozieł, Dorota, Reed, Mike, Oreiro, Raquel, Silvotti, Roberto, Siwak, Michał, Heber, Uli, Papics, Peter

“…We present early results of the application of a method which uses multicolor photometry and spectroscopy for ℓ discrimination. This method has been…”
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An Observational Study of Contact Binaries with Large Temperature Differences Between Components by Siwak, Michal

“…In this paper we investigate a sample of contact eclipsing binary systems, which exhibit a large temperature difference (at least 1000 K) between the…”
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Disc light variability in the FUor star V646 Puppis as observed by TESS and from the ground by Siwak, Michał, Ogłoza, Waldemar, Krzesiński, Jerzy

“…A&A 644, A135 (2020) We investigate small-scale light variations in V646 Pup occurring on different timescales with the aim to investigate whether this…”
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Photometric variability of TW Hya from seconds to years as seen from space and the ground during 2013–2017 by Siwak, Michal, Ogloza, Waldemar, Moffat, Anthony F J, Matthews, Jaymie M, Rucinski, Slavek M, Kallinger, Thomas, Kuschnig, Rainer, Cameron, Chris, Weiss, Werner W, Rowe, Jason F, Guenther, David B, Sasselov, Dimitar

“…Abstract This is the final photometric study of TW Hya based on new MOST satellite observations. During 2014 and 2017, the light curves showed stable 3.75- and…”
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Optical variability of eight FRII-type quasars with 13-yr photometric light curves by Kuźmicz, Agnieszka, Goyal, Arti, Zola, Stanisław, Jamrozy, Marek, Dróżdż, Marek, Ogłoza, Waldemar, Siwak, Michał, Reichart, Daniel E, Kouprianov, Vladimir V, Caton, Daniel B

“…We characterize the optical variability properties of eight lobe-dominated radio quasars (QSOs): B2 0709$+$37, FBQS J095206.3$+$235245, PG 1004$+$130, [HB89]…”
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Mount Suhora high cadence photometric survey of T Tauri-type stars by Siwak, Michał, Dróżdż, Marek, Gut, Karol, Winiarski, Maciej, Ogłoza, Waldemar, Stachowski, Grzegorz

“…2019AcA...69..227S Results of high-cadence multi-colour observations of 121 pre-main sequence stars available from the northern hemisphere are presented. The…”
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Stable and unstable accretion in the classical T Tauri stars IM Lup and RU Lup as observed by MOST by Siwak, Michal, Ogloza, Waldemar, Rucinski, Slavek M, Moffat, Anthony F J, Matthews, Jaymie M, Cameron, Chris, Guenther, David B, Kuschnig, Rainer, Rowe, Jason F, Sasselov, Dimitar, Weiss, Werner W

“…Results of the time variability monitoring of the two classical T Tauri stars, RU Lup and IM Lup, are presented. Three photometric data sets were utilized: (1)…”
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Mean-field approximation for two- and three-person Prisoner’s Dilemmas by Platkowski, Tadeusz, Siwak, Michal

“…We consider the mean-field approximation (MFA) to the system of interacting agents playing two- and three-person Prisoner’s Dilemma games (2-PD and 3-PD). The…”
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Gaia21bty: An EXor lightcurve exhibiting an FUor spectrum by Siwak, Michał, Hillenbrand, Lynne A, Kóspál, Ágnes, Ábrahám, Péter, Giannini, Teresa, De, Kishalay, Moór, Attila, Szilágyi, Máté, Janík, Jan, Koen, Chris, Park, Sunkyung, Nagy, Zsófia, de Miera, Fernando Cruz-Sáenz, Fiorellino, Eleonora, Marton, Gábor, Kun, Mária, Lucas, Philip W, Udalski, Andrzej, Szabó, Zsófia Marianna

“…Gaia21bty, a pre-main sequence star that previously had shown aperiodic dips in its light curve, underwent a considerable $\Delta G\approx2.9$ mag brightening…”
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