Results 41 to 50 of about 837,700 (191)

The Evolution of Stellar X-Ray Activity and Angular Momentum as Seen by eROSITA, TESS, and Gaia

The Astrophysical Journal Letters
We have assembled a sample of ∼8200 stars with spectral types F5V–M5V, all having directly measured X-ray luminosities from eROSITA and rotation periods from TESS and having empirically estimated ages via their membership in stellar clusters and groups ...
Keivan G. Stassun, Marina Kounkel
doaj   +1 more source

Radiative Transfer in 3D Model Stellar Atmospheres

, 2003
Recently 3D hydrodynamical simulations of stellar surface convection have become feasible thanks to advances in computer technology and efficient numerical algorithms. Available observational diagnostics indicate that these models are highly realistic in
Asplund, Martin,, Collet, Remo,
core   +8 more sources

Older Ages for 23 Pre-main Sequence Stars in Upper Scorpius Using Dynamical-mass-constrained Stellar Evolutionary Models

The Astrophysical Journal
We present revised stellar ages for 23 pre-main-sequence (PMS) K- and M-type stars in the Upper Scorpius (Upper Sco) star-forming region, derived using stellar dynamical masses to constrain isochronal ages from five PMS stellar evolutionary models.
A. P. M. Towner, J. A. Eisner, P. D. Sheehan, L. A. Hillenbrand, Y.-L. Wu   +4 more
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Tracing kinematic (mis)alignments in CALIFA merging galaxies : Stellar and ionized gas kinematic orientations at every merger stage [PDF]

, 2015
J.M.A. and V.W. acknowledge support from the European Research Council Starting Grant (SEDmorph; P.I. V. Wild).We present spatially resolved stellar and/or ionized gas kinematic properties for a sample of 103 interacting galaxies, tracing all merger ...
Ziegler, Katharina B., Bekeraitė, S., D. Mast, Verdes-Montenegro, L., Mcintosh, D., Monreal-Ibero, A., González Delgado, R. M., Aguerri, J., Sánchez, S. F., Lyubenova, M., Kehrig, C., J. Falcón-Barroso, Vílchez, J., Sanchez, Sébastien, García-Benito, R., D. H. McIntosh, J. K. Barrera-Ballesteros, G. van de Ven, Ziegler, B., del Olmo, A., Wild, V., González Delgado, R., Barrera-Ballesteros, J., B. García-Lorenzo, R. García-Benito, García-Lorenzo, B., Méndez-Abreu, J., V. Wild, Cortijo-Ferrero, C., Bomans, D. J., J. Méndez-Abreu, A. Monreal-Ibero, B. Husemann, Iglesias-Paramo, J., Marquez, I., Mast, Damian, Bland-Hawthorn, J., L. Verdes-Montenegro, van de Ven, G., Marino, R. A., R. M. González Delgado, C. J. Walcher, M. Lyubenova, A. del Olmo, Mast, D., I. Marquez, S. Bekeraitė, McIntosh, D. H., Husemann, B., Barrera-Ballesteros, J.K., Aguerri, J. A. L., J. A. L. Aguerri, Barrera-Ballesteros, J. K., Marino, R., J. M. Vílchez, J. Iglesias-Paramo, Marino, R.A., D. J. Bomans, J. Bland-Hawthorn, Walcher, C. J., McIntosh, D.H., R. A. Marino, B. Ziegler, Walcher, C., S. F. Sánchez, Bomans, D., C. Kehrig, Vílchez, J. M., J. Masegosa, Falcón-Barroso, J., Masegosa, J., C. Cortijo-Ferrero   +71 more
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Anchoring Stellar Age Indicators: A Cross Calibration of [C/N] and Gyrochronology Ages via the Age–Velocity Dispersion Relation

The Astronomical Journal
Determining stellar ages is challenging, as it depends on other stellar parameters in a nonlinear way and often relies on stellar evolution models to infer the underlying relation between these parameters and age. This complexity increases when comparing
Yuxi(Lucy) Lu, Marc H. Pinsonneault, Yuan-Sen Ting, Phil R. Van-Lane, John D. Roberts, Jamie Tayar, Alexander Stone-Martinez, Amanda L. Ash   +7 more
doaj   +1 more source

The age distribution of stellar clusters in M83 [PDF]

Monthly Notices of the Royal Astronomical Society: Letters, 2014
Abstract In order to empirically determine the time-scale and environmental dependence of stellar cluster disruption, we have undertaken an analysis of the unprecedented multipointing (seven), multiwavelength (U, B, V, Hα, and I) Hubble Space Telescope imaging survey of the nearby, face-on spiral galaxy M83. The images are used to locate
E. Silva-Villa, A. Adamo, N. Bastian, M. Fouesneau, E. Zackrisson   +4 more
openaire   +1 more source

Constraining Stellar Rotation at the Zero-age Main Sequence with TESS [PDF]

The zero-age main sequence (ZAMS) is a critical phase for stellar angular momentum evolution, as stars transition from contraction-dominated spin-up to magnetic wind-dominated spin-down.
A. A. Breimann, Pérez Chávez, J. A., Cargile, P. A., Pérez Chávez, J. A., Matt, S. P., Huang, C. X., S. P. Matt, G. Zhou, Zhou, G., J. A. Pérez Chávez, C. X. Huang, Breimann, A. A., Wright, N. J., P. A. Cargile, N. J. Wright, Douglas, S. T., S. T. Douglas, Douglas, S. T,   +17 more
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Relations of Rotation and Chromospheric Activity to Stellar Age for FGK Dwarfs from Kepler and LAMOST

The Astrophysical Journal Supplement Series
The empirical relations between rotation period, chromospheric activity, and age can be used to estimate stellar age. To calibrate these relations, we present a catalog, including the masses and ages of 52,321 FGK dwarfs, 47,489 chromospheric activity ...
Lifei Ye, Shaolan Bi, Jinghua Zhang, Tiancheng Sun, Liu Long, Zhishuai Ge, Tanda Li, Xianfei Zhang, Xunzhou Chen, Yaguang Li, Jianzhao Zhou, Maosheng Xiang   +11 more
doaj   +1 more source

The California Legacy Survey. VI. The Fate of Activity Cycles in Sun-like Stars

The Astronomical Journal
We analyze the spectra of 91 solar-type G- and K-type main-sequence dwarfs in the solar neighborhood to assess activity trends with stellar properties.
Howard Isaacson, Stephen R. Kane, Brad Carter, Andrew W. Howard   +3 more
doaj   +1 more source

A Search for Stellar Siblings of the ∼200 Myr TOI-251 b Planetary System

The Astrophysical Journal, 2023
Young planets (
Qinghui Sun, Sharon Xuesong Wang, Andrew W. Mann, Benjamin M. Tofflemire, Adam L. Kraus, Tianjun Gan, Madyson G. Barber   +6 more
doaj   +1 more source