The first Doppler imaging of the active binary prototype RS Canum Venaticorum
| Autor: | Xiang, Yue, Gu, Shenghong, Wolter, U., Schmitt, J. H. M. M., Cameron, A. Collier, Barnes, J. R., Mittag, M., Perdelwitz, V., Kohl, S. |
|---|---|
| Rok vydání: | 2020 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1093/mnras/staa063 |
| Popis: | We present the first Doppler images of the prototypical active binary star RS CVn, derived from high-resolution spectra observed in 2004, 2016 and 2017, using three different telescopes and observing sites. We apply the least-squares deconvolution technique to all observed spectra to obtain high signal-to-noise line profiles, which are used to derive the surface images of the active K-type component. Our images show a complex spot pattern on the K star, distributed widely in longitude. All starspots revealed by our Doppler images are located below a latitude of about 70$^{\circ}$. In accordance with previous light-curve modeling studies, we find no indication of a polar spot on the K star. Using Doppler images derived from two consecutive rotational cycles, we estimate a surface differential rotation rate of $\Delta\Omega = -0.039 \pm 0.003 ~rad~d^{-1}$ and $\alpha = \Delta\Omega/\Omega_{eq} = -0.030 \pm 0.002$ for the K star. Given the limited phase coverage during those two rotations, the uncertainty of our differential rotation estimate is presumably higher. Comment: 11 pages, 10 figures, accepted for publication in MNRAS |
| Databáze: | arXiv |
| Externí odkaz: |
|