Results 21 to 30 of about 250 (146)
A New Approach to the Long-Term Activity Behavior of DM UMa
Open Astronomy, 2012 A long-term activity character of DM UMa (K0-1 IV-III), which is one of the most active members of the RS CVn type variables, is examined using the multicolor photometric observations which spread to the time interval between 1980 and 2009. In this work,
Taş G., Evren S.
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Joint Modeling of Radial Velocities and Photometry with a Gaussian Process Framework
The Astrophysical Journal, 2023 Developments in the stability of modern spectrographs have led to extremely precise instrumental radial velocity (RV) measurements. For most stars, the detection limit of planetary companions with these instruments is expected to be dominated by ...
Quang H. Tran +3 more
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Light curve analysis of W-UMa type binary systems RZ UMi, OQ UMa, LP UMa [PDF]
Serbian Astronomical JournalThis study presents new, high-quality, optical photometric observations of three W-UMa type contact binaries. The analysis of the corresponding light curves is made using Djurašević's inverse problem method.
Grozdanović M., Đurašević G.
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Contemporaneous Observations of Hα Luminosities and Photometric Amplitudes for M Dwarfs
The Astronomical Journal, 2023 While many M dwarfs are known to have strong magnetic fields and high levels of magnetic activity, we are still unsure about the properties of their starspots and the origin of their magnetic dynamos.
Aylin García Soto +4 more
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Asteroseismic Signature of a Large Active Region
Frontiers in Astronomy and Space Sciences, 2019 Axisymmetric magnetic activity on the Sun and sun-like stars increases the frequencies of the modes of acoustic oscillation. However, it is unclear how a corotating patch of activity affects the oscillations, since such a perturbation is unsteady in the ...
Emanuele Papini +2 more
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Overfitting Affects the Reliability of Radial Velocity Mass Estimates of the V1298 Tau Planets
The Astronomical Journal, 2023 Mass, radius, and age measurements of young (≲100 Myr) planets have the power to shape our understanding of planet formation. However, young stars tend to be extremely variable in both photometry and radial velocity (RV) measurements, which makes ...
Sarah Blunt +25 more
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Starspots on by DRA-Type Stars [PDF]
Highlights of Astronomy, 1977 The first detection of spots on dwarf M stars was by Kron on YY Geminorum in 1948. Since then phenomena attributable to starspots have been found by numerous authors beginning with Kraft and Krzeminski on the star now known as BY Draconis and on CC Eridani by Evans.
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The Astrophysical Journal Letters, 2023 Planets orbiting M-dwarf stars are prime targets in the search for rocky exoplanet atmospheres. The small size of M dwarfs renders their planets exceptional targets for transmission spectroscopy, facilitating atmospheric characterization.
Sarah E. Moran +23 more
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Interferometric Images of the Starspot Evolution of ζ Andromedae
The Astrophysical JournalThe evolution of starspots of the giant primaries of RS CVn systems is typically detected indirectly with photometric and spectroscopic monitoring. These observations suggest slowly-evolving stellar surfaces and can constrain differential rotation as ...
Rachael M. Roettenbacher +23 more
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Benchmarking pre-main sequence stellar evolutionary tracks using disk-based dynamical stellar masses
Astronomy & AstrophysicsStellar masses are a fundamental property to understand models of pre-main sequence evolution, but their values derived from Hertzsprung–Russell (HR) diagrams are strongly model dependent.
Zallio Luigi +16 more
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