The Origin of Weakened Magnetic Braking in Old Solar Analogs
| العنوان: | The Origin of Weakened Magnetic Braking in Old Solar Analogs |
|---|---|
| المؤلفون: | Travis S. Metcalfe, Adam J. Finley, Oleg Kochukhov, Victor See, Thomas R. Ayres, Keivan G. Stassun, Jennifer L. van Saders, Catherine A. Clark, Diego Godoy-Rivera, Ilya V. Ilyin, Marc H. Pinsonneault, Klaus G. Strassmeier, Pascal Petit |
| المساهمون: | Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Centre National d'Études Spatiales [Toulouse] (CNES) |
| المصدر: | The Astrophysical Journal Letters The Astrophysical Journal Letters, 2022, 933, ⟨10.3847/2041-8213/ac794d⟩ |
| بيانات النشر: | HAL CCSD, 2022. |
| سنة النشر: | 2022 |
| مصطلحات موضوعية: | [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], FOS: Physical sciences, Stellar winds, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Stellar evolution, Stellar magnetic fields, Solar analogs, Astrophysics - Solar and Stellar Astrophysics, Astronomi, astrofysik och kosmologi, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics::Solar and Stellar Astrophysics, Astronomy, Astrophysics and Cosmology, Astrophysics::Earth and Planetary Astrophysics, Spectropolarimetry, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR) |
| الوصف: | The rotation rates of main-sequence stars slow over time as they gradually lose angular momentum to their magnetized stellar winds. The rate of angular momentum loss depends on the strength and morphology of the magnetic field, the mass-loss rate, and the stellar rotation period, mass, and radius. Previous observations suggested a shift in magnetic morphology between two F-type stars with similar rotation rates but very different ages (88 Leo and rho CrB). In this Letter, we identify a comparable transition in an evolutionary sequence of solar analogs with ages between 2-7 Gyr. We present new spectropolarimetry of 18 Sco and 16 Cyg A & B from the Large Binocular Telescope, and we reanalyze previously published Zeeman Doppler images of HD 76151 and 18 Sco, providing additional constraints on the nature and timing of this transition. We combine archival X-ray observations with updated distances from Gaia to estimate mass-loss rates, and we adopt precise stellar properties from asteroseismology and other sources. We then calculate the wind braking torque for each star in the evolutionary sequence, demonstrating that the rate of angular momentum loss drops by more than an order of magnitude between the ages of HD 76151 and 18 Sco (2.6-3.7 Gyr) and continues to decrease modestly to the age of 16 Cyg A & B (7 Gyr). We suggest that this magnetic transition may represent a disruption of the global dynamo arising from weaker differential rotation, and we outline plans to probe this phenomenon in additional stars spanning a wide range of spectral types. 6 pages including 2 figures and 1 table. ApJ Letters (accepted June 16) |
| وصف الملف: | application/pdf |
| اللغة: | English |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f1a3585a0b9440c81c309456b7e13588 https://insu.hal.science/insu-03745323 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....f1a3585a0b9440c81c309456b7e13588 |
| قاعدة البيانات: | OpenAIRE |
| الوصف غير متاح. |