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Using a neural network approach and starspots dependent models to predict effective temperatures and ages of young stars. [PDF]
PLoS ONEThis study presents a statistical approach to accurately predict the effective temperatures of pre-main sequence stars, which are necessary for determining stellar ages using the isochrone methodology and cutting-age starspots-dependent models.
Marco Tarantino +4 more
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Starspots: A Key to the Stellar Dynamo [PDF]
Living Reviews in Solar Physics, 2005 Magnetic activity similar to that of the Sun is observed on a variety of cool stars with external convection envelopes. Stellar rotation coupled with convective motions generate strong magnetic fields in the stellar interior and produce a multitude of ...
Berdyugina Svetlana V.
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Torus-stable zone above starspots [PDF]
Monthly Notices of the Royal Astronomical Society, 2021 ABSTRACT Whilst intense solar flares are almost always accompanied by a coronal mass ejection (CME), reports on stellar CMEs are rare, despite the frequent detection of stellar ‘super flares’. The torus instability of magnetic flux ropes is believed to be one of the main driving mechanisms of solar CMEs.
Xudong Sun +2 more
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Starspot activity of HD 199178. Doppler images from 1994--2017 [PDF]
Astronomy & Astrophysics, 2018 Context. Studying the spots of late-type stars is crucial for distinguishing between the various proposed dynamo mechanisms believed to be the main cause of starspot activity. For this research it is important to collect observation time series that are long enough to unravel both long- and short-term spot evolution. Doppler imaging is a very efficient
T. Hackman +6 more
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The Astrophysical JournalStarspots are ubiquitous in young, low-mass stars, yet their impact on the spectral classification and fundamental parameter inference of pre-main-sequence stars (PMS) has been largely overlooked.
Facundo Pérez Paolino +4 more
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Starspot photometry with robotic telescopes [PDF]
Astronomy and Astrophysics Supplement Series, 1997 We report on the progress of our ongoing photometric monitoring program of spotted late-type stars with automatic photoelectric telescopes (APTs) on Mt. Hopkins in Arizona and on Mt. Etna in Sicily. We present 9 250 differential UBV and/or observations for altogether 23 chromospherically active stars, singles and binaries, pre main sequence and post ...
K. G. Strassmeier +3 more
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Starspots and Undetected Binary Stars Have Distinct Signatures in Young Stellar Associations [PDF]
The Astrophysical JournalYoung stars form in associations, meaning that young stellar associations provide an ideal environment to measure the age of a nominally coeval population.
Kendall Sullivan, Adam L. Kraus
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Long-term Doppler imaging of the star XX Trianguli indicates chaotic non-periodic dynamo [PDF]
Nature CommunicationsSunspots are the most well-known manifestations of solar magnetic fields and exhibit a range of phenomena related to the interior dynamo. Starspots are the direct analogs of sunspots on other stars but with the big observational restriction that we ...
K. G. Strassmeier +3 more
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Magnetic activities of two contact binaries in quadruple stellar systems [PDF]
Scientific ReportsBased on observations from the Transiting Exoplanet Survey Satellite (TESS), we conducted a comprehensive study of two contact binaries, V752 Cen and HT Vir, in 2+2-type hierarchical quadruple stellar systems.
Yuangui Yang, Shuang Wang
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Starspot Distribution and Flare Events in Two Young Low-mass Stars Using TESS Data
The Astrophysical JournalWide-field high-precision photometric observations such as the Transiting Exoplanet Survey Satellite (TESS) allowed the investigation of the stellar magnetic activity of cool stars. M dwarf starspots and stellar flares are the main indicators of magnetic
Rajib Kumbhakar +3 more
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