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Related papers: Chromospheric activity as age indicator

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Finding solar-analog stars with fundamental properties as close as possible to the Sun and studying the characteristics of their surface magnetic activity is a very promising way to understand the solar variability and its associated dynamo…

The orbit distribution of young stars in the Galactic disk is highly structured, from well-defined clusters to streams of stars that may be widely dispersed across the sky, but are compact in orbital action-angle space. The age distribution…

Astrophysics of Galaxies · Physics 2023-11-20 Verena Fürnkranz , Hans-Walter Rix , Johanna Coronado , Rhys Seeburger

We investigate magnetic activity properties of 21 stars via medium resolution optical spectra and long-term photometry. Applying synthetic spectrum fitting method, we find that all targets are cool giant or sub-giant stars possessing…

Solar and Stellar Astrophysics · Physics 2021-06-23 Orkun Özdarcan

Due to its unique long-term coverage and high photometric precision, observations from the Kepler asteroseismic investigation will provide us with the possibility to sound stellar cycles in a number of solar-type stars with…

Solar and Stellar Astrophysics · Physics 2015-05-14 C. Karoff , T. S. Metcalfe , W. J. Chaplin , S. Frandsen , F. Grundahl , H. Kjeldsen , D. Buzasi , T. Arentoft , J. Christensen-Dalsgaard

Determining stellar ages is challenging, as it depends on other stellar parameters in a non-linear way and often relies on stellar evolution models to infer the underlying relation between these parameters and age. This complexity increases…

Solar and Stellar Astrophysics · Physics 2025-07-01 Yuxi Lu , Marc H. Pinsonneault , Yuan-Sen Ting , Phil R. Van-Lane , John D Roberts , Jamie Tayar , Alexander Stone-Martinez

We present the results of a study of the stellar activity in the solar neighborhood using complete kinematics (galactocentric velocities U,V,W) and the chromospheric activity index $\log R'_{\rm{HK}}$. We analyzed the average activity level…

Solar and Stellar Astrophysics · Physics 2015-06-15 F. Murgas , J. S. Jenkins , P. Rojo , H. R. A Jones , D. J. Pinfield

Over the past 40 years, observational surveys have established the existence of a tight relationship between a star's age, rotation period, and magnetic activity. This age-rotation-activity relation documents the interplay between a star's…

Solar and Stellar Astrophysics · Physics 2010-12-02 Kevin R. Covey , Marcel A. Agueros , Jenna J. Lemonias , Nicholas M. Law , Adam L. Kraus

We present our latest results on the solar-stellar connection by studying 18 solar analogs that we identified among the Kepler seismic sample (Salabert et al., 2016a). We measured their magnetic activity properties using observations…

Solar and Stellar Astrophysics · Physics 2016-10-10 D. Salabert , R. A. Garcia. P. G. Beck , the SSA team

The atmospheric activity of the Sun and solar-type stars is analysed involving observations from HK-project at the Mount Wilson Observatory, the California and Carnegie Planet Search Program at the Keck and Lick Observatories, and the…

Solar and Stellar Astrophysics · Physics 2015-09-08 E. A. Bruevich , V. V. Bruevich , E. V. Shimanovskaya

In this paper we investigate how the chemical and kinematic properties of stars vary as a function of age. Using data from a variety of photometric, astrometric and spectroscopic surveys, we calculate the ages, phase space information and…

Astrophysics of Galaxies · Physics 2018-06-27 John J. Vickers , Martin C. Smith

Context. Signatures of chromospheric activity enhancement have been found for a dozen stars, pointing to a possible star-planet interaction. Nevertheless in the coronal activity regime, there is no conclusive observational evidence for such…

Earth and Planetary Astrophysics · Physics 2011-05-06 B. L. Canto Martins , M. L. das Chagas , S. Alves , I. C. Leão , L. P. de Souza Neto , J. R. de Medeiros

Solar simulations and observations show that the detection of long-period Earth-like planets is expected to be very difficult with radial velocity techniques in the solar case because of activity. The inhibition of the convective blueshift…

Solar and Stellar Astrophysics · Physics 2019-07-10 N. Meunier , A. -M. Lagrange , T. Boulet , S. Borgniet

The orbital properties of stars in the disk are signatures of their formation, but they are also expected to change over time due to the dynamical evolution of the Galaxy. Stellar orbits can be quantified by three dynamical actions, J_r,…

Solar and Stellar Astrophysics · Physics 2018-12-27 Angus Beane , Melissa K. Ness , Megan Bedell

We analyze the X-ray emission and chromospheric activity of Sun-like stars of F, G and K spectral classes (late-type stars) studied in the framework of the HK project. More powerful coronas are possessed by stars displaying irregular…

Solar and Stellar Astrophysics · Physics 2018-07-19 E. A. Bruevich , M. M. Katsova , D. D. Sokolov

Solar seismology has allowed precision measurements of both the static and dynamic structure of our local star, the Sun. In the near future, seismology of solar-like stars of different ages and masses, necessarily restricted by angular…

Astrophysics · Physics 2007-05-23 George R. Isaak , Kate G. Isaak

Ages, metallicities, space velocities, and Galactic orbits of stars in the Solar neighbourhood are fundamental observational constraints on models of galactic disk evolution. We aim to consolidate the calibrations of uvby photometry into…

Astrophysics · Physics 2009-11-13 J. Holmberg , B. Nordstrom , J. Andersen

We study the differences in chromospheric structure induced in K stars by stellar activity, to expand our previous work for G stars, including the Sun as a star. We selected six stars of spectral type K with 0.82$<B-V<$0.90, including the…

Solar and Stellar Astrophysics · Physics 2015-05-13 Mariela Vieytes , Pablo Mauas , Rodrigo Diaz

(abridged) A method for simulating light curves containing stellar micro-variability for a range of spectral types and ages, based on parameter-by-parameter scaling of a multi-component fit to the solar irradiance power spectrum (from…

Astrophysics · Physics 2009-11-10 S. Aigrain , F. Favata , G. Gilmore

We present a study of rotation (vsini) and chromospheric activity (Halpha EW) based on an extensive set of high-resolution optical spectra obtained with MIKE on the 6.5m Magellan Clay telescope. Our targets are 74 F-M dwarfs in the young…

Astrophysics · Physics 2009-11-13 Aleks Scholz , Jaime Coffey , Alexis Brandeker , Ray Jayawardhana

Obtaining measurements of chromospheric and photometric activity of stars with near-solar fundamental parameters and rotation periods is important for a better understanding of solar-stellar connection. We select a sample of 2603 stars with…

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