دورية أكاديمية
Correlating Changes in Spot Filling Factors With Stellar Rotation: The Case of Lkca 4
| العنوان: | Correlating Changes in Spot Filling Factors With Stellar Rotation: The Case of Lkca 4 |
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| المؤلفون: | Pérez Paolino, Facundo, Bary, Jeffrey S., Petersen, Michael S., Ward-Duong, Kimberly, Tofflemire, Benjamin M., Follette, Katherine B., Mach, Heidi |
| المصدر: | Astronomy: Faculty Publications |
| بيانات النشر: | Smith ScholarWorks |
| سنة النشر: | 2023 |
| المجموعة: | Smith College: Smith ScholarWorks |
| مصطلحات موضوعية: | Astrophysics and Astronomy |
| الوصف: | We present a multi-epoch spectroscopic study of LkCa 4, a heavily spotted non-accreting T Tauri star. Using SpeX at NASA’s Infrared Telescope Facility (IRTF), 12 spectra were collected over five consecutive nights, spanning ≈1.5 stellar rotations. Using the IRTF SpeX Spectral Library, we constructed empirical composite models of spotted stars by combining a warmer (photosphere) standard star spectrum with a cooler (spot) standard weighted by the spot filling factor, f spot. The best-fit models spanned two photospheric component temperatures, T phot = 4100 K (K7V) and 4400 K (K5V), and one spot component temperature, T spot = 3060 K (M5V) with an A V of 0.3. We find values of f spot to vary between 0.77 and 0.94 with an average uncertainty of ∼0.04. The variability of f spot is periodic and correlates with its 3.374 day rotational period. Using a mean value for f meanspot to represent the total spot coverage, we calculated spot corrected values for T eff and L ⋆. Placing these values alongside evolutionary models developed for heavily spotted young stars, we infer mass and age ranges of 0.45-0.6 M ⊙ and 0.50-1.25 Myr, respectively. These inferred values represent a twofold increase in the mass and a twofold decrease in the age as compared to standard evolutionary models. Such a result highlights the need for constraining the contributions of cool and warm regions of young stellar atmospheres when estimating T eff and L ⋆ to infer masses and ages as well as the necessity for models to account for the effects of these regions on the early evolution of low-mass stars. |
| نوع الوثيقة: | text |
| وصف الملف: | application/pdf |
| اللغة: | unknown |
| العلاقة: | https://scholarworks.smith.edu/ast_facpubs/89Test; https://scholarworks.smith.edu/context/ast_facpubs/article/1088/viewcontent/Correlating_Changes_In_Spot_Filling_Factors_With_Stellar_Rotation__The_Case_of_Lkca_4.pdfTest |
| DOI: | 10.3847/1538-4357/acbb61 |
| الإتاحة: | https://doi.org/10.3847/1538-4357/acbb61Test https://scholarworks.smith.edu/ast_facpubs/89Test https://scholarworks.smith.edu/context/ast_facpubs/article/1088/viewcontent/Correlating_Changes_In_Spot_Filling_Factors_With_Stellar_Rotation__The_Case_of_Lkca_4.pdfTest |
| حقوق: | © 2023. The Author(s) ; http://creativecommons.org/licenses/by/4.0Test/ |
| رقم الانضمام: | edsbas.5CEBDA7B |
| قاعدة البيانات: | BASE |
| DOI: | 10.3847/1538-4357/acbb61 |
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