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arXiv · 0711.1187

Anti-solar differential rotation and surface flow pattern on UZ Librae

K. Vida·Zs. Kővári·M. Švanda·K. Oláh·K. G. Strassmeier·J. Bartus·E. Forgács-Dajka
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Abstract

We re-investigate UZ Librae spectra obtained at KPNO in 1998 and 2000. From the 1998 data we compose 11 consecutive Doppler images using the Ca I-6439, Fe I-6393 and Fe I-6411 lines. Applying the method of average cross-correlation of contiguous Doppler images we find anti-solar differential rotation with a surface shear of alpha ~ -0.03. The pilot application of the local correlation tracking technique for the same data qualitatively confirms this result and indicates complex flow pattern on the stellar surface. From the cross-correlation of the two available Doppler images in 2000 we also get anti-solar differential rotation but with a much weaker shear of alpha ~ -0.004.

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K. Vida, Zs. Kővári, M. Švanda, K. Oláh, K. G. Strassmeier, J. Bartus, E. Forgács-Dajka. 2007-11-07. Anti-solar differential rotation and surface flow pattern on UZ Librae. https://doi.org/10.1002/asna.200710879

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