Search Results - "Jetsu, L"

General Model for Light Curves of Chromospherically Active Binary Stars by Jetsu, L., Henry, G. W., Lehtinen, J.

“…Abstract The starspots on the surface of many chromospherically active binary stars concentrate on long-lived active longitudes separated by 180°. Shifts in…”
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DID THE ANCIENT EGYPTIANS RECORD THE PERIOD OF THE ECLIPSING BINARY ALGOL—THE RAGING ONE? by Jetsu, L, Porceddu, S, Lyytinen, J, KAJATKARI, P, Lehtinen, J, Markkanen, T, Toivari-Viitala, J

“…The eclipses in binary stars give precise information of orbital period changes. Goodricke discovered the 2.867 day period in the eclipses of Algol in the year…”
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Some Studies of Terrestrial Impact Cratering Rate by Jetsu L.

“…In 1984, a 28.4 Myr periodicity was detected in the ages of terrestrial impact craters and a 26 Myr periodicity in the epochs of mass extinctions of species…”
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Time‐series analysis of long‐term photometry of BM Canum Venaticorum by Siltala, L., Jetsu, L., Hackman, T., Henry, G. W., Immonen, L., Kajatkari, P., Lankinen, J., Lehtinen, J., Monira, S., Nikbakhsh, S., Viitanen, A., Viuho, J., Willamo, T.

“…Long‐term photometry is commonly used to monitor chromospheric activity of late–type stars. We study standard Johnson differential V photometry of the RS CVn…”
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Spot activity of II Peg by Hackman, T., Mantere, M.J., Jetsu, L., Ilyin, I., Kajatkari, P., Kochukhov, O., Lehtinen, J., Lindborg, M., Piskunov, N., Tuominen, I.

“…We have studied the long‐term spot activity of the RS CVn star II Peg by means of Doppler imaging based on spectroscopy and time series analysis of photometry…”
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General Model for Light Curves of Chromospherically Active Binary Stars∗ ∗ The CPS results are available electronically at the Vizier database by Jetsu, L., Henry, G. W., Lehtinen, J.

“…The starspots on the surface of many chromospherically active binary stars concentrate on long-lived active longitudes separated by 180°. Shifts in activity…”
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Discrete Chi-square Method for Detecting Many Signals by Jetsu, Lauri

“…Unambiguous detection of signals superimposed on unknown trends is difficult for unevenly spaced data. Here, we formulate the Discrete Chi-square Method (DCM)…”
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Say hello to Algol's new companion candidates by Jetsu, L

“…2021, The Astrophysical Journal 920, A137 Constant orbital period ephemerides of eclipsing binaries give the computed eclipse epochs (C). These ephemerides…”
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About ten stars orbit eclipsing binary XZ And by Jetsu, L

“…A third body in an eclipsing binary system causes regular periodic changes in the observed (O) minus the computed (C) eclipse epochs. Fourth bodies are rarely…”
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Real light curves of FK Comae Berenices: Farewell flip-flop by Jetsu, L

“…For seven decades, the widely held view has been that the formation, the migration and the decay of short-lived starspots explain the constantly changing light…”
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Real light curves of FK Comae Berenices: Dead end by Jetsu, L

“…Recently, we presented a general model for the light curves of chromospherically active stars, where the observed light curve is interference of two real…”
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General Model for Light curves of Chromospherically Active Binary Stars by Jetsu, L, Henry, G. W, Lehtinen, J

“…The starspots on the surface of many chromospherically active binary stars concentrate on long--lived active longitudes separated by 180 degrees. The activity…”
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Long-term spot monitoring of the young solar analogue V889 Her by Willamo, T, Hackman, T, Lehtinen, J. J, Käpylä, M. J, Ilyin, I, Henry, G. W, Jetsu, L, Kochukhov, O, Piskunov, N

“…A&A 622, A170 (2019) Starspots are important manifestations of stellar magnetic activity. By studying their behaviour in young solar analogues, we can unravel…”
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Spot activity of LQ Hya from photometry between 1988 and 2011 by Lehtinen, J, Jetsu, L, Hackman, T, Kajatkari, P, Henry, G. W

“…We investigate the spot activity of the young chromospherically active main sequence star LQ Hya. Our aims are to identify possible active longitudes, estimate…”
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Analysing the active longitudes of the young solar analogue HD 116956 using Bayesian statistics by Lehtinen, J, Jetsu, L, Mantere, M. J

“…Aims: In this study, we aim at investigating the properties of the active longitude system of the young solar analogue HD 116956 in detail, especially…”
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Spot activity of the RS CVn star {\sigma} Geminorum by Kajatkari, P, Hackman, T, Jetsu, L, Lehtinen, J, Henry, G. W

“…We model the photometry of RS CVn star $\sigma$ Geminorum to obtain new information on the changes of the surface starspot distribution, i.e., activity cycles,…”
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Time series analysis of long-term photometry of BM Canum Venaticorum by Siltala, L, Jetsu, L, Hackman, T, Henry, G. W, Immonen, L, Kajatkari, P, Lankinen, J, Lehtinen, J, Monira, S, Nikbakhsh, S, Viitanen, A, Viuho, J, Willamo, T

“…Studying RS CVn binaries is challenging, because in addition to spot activity, other effects such as mass transfer between the components and gravitational…”
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Did the ancient egyptians record the period of the eclipsing binary Algol - the Raging one? by Jetsu, L, Porceddu, S, Lyytinen, J, Kajatkari, P, Lehtinen, J, Markkanen, T, Toivari-Viitala, J

“…The eclipses in binary stars give precise information of orbital period changes. Goodricke discovered the 2.867 days period in the eclipses of Algol in the…”
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The continuous period search method and its application to the young solar analogue HD 116956 by Lehtinen, J, Jetsu, L, Hackman, T, Kajatkari, P, Henry, G. W

“…We formulate an improved time series analysis method for the analysis of photometry of active stars. This new Continuous Period Search (CPS) method is applied…”
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Periodicity in some light curves of the solar analogue V352 CMa by Kajatkari, P, Jetsu, L, Cole, E, Hackman, T, Henry, G. W, Joutsiniemi, S-L, Lehtinen, J, Mäkelä, V, Porceddu, S, Ryynänen, K, Şolea, V

“…Our aim was to study the light curve periodicity of the solar analogue V352 CMa and in particular show that the presence or absence of periodicity in low…”
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