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arXiv · 1309.1378

Surface differential rotation of IL Hya from time-series Doppler images

Zsolt Kővári·Levente Kriskovics·Katalin Oláh·Krisztián Vida·János Bartus·Klaus G. Strassmeier·Michael Weber
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Abstract

We present a time-series Doppler imaging study of the K-subgiant component in the RS CVn-type binary system IL Hya (P orb=12.905 d). From re-processing the unique long-term spectroscopic dataset of 70 days taken in 1996/97, we perform a thorough cross-correlation analysis to derive surface differential rotation. As a result we get solar-type differential rotation with a shear value alpha of 0.05, in agreement with preliminary suggestions from previous attempts. A possible surface pattern of meridional circulation is also detected.

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Zsolt Kővári, Levente Kriskovics, Katalin Oláh, Krisztián Vida, János Bartus, Klaus G. Strassmeier, Michael Weber. 2013-09-05. Surface differential rotation of IL Hya from time-series Doppler images. https://doi.org/10.1017/s1743921314002543

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