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

摘要

Were-investigate UZ Libr ae 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 approximate to -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 approximate to -0.004. (c) 2007 WILEY-VCH Verlag GmbH&Co. KGaA, Weinheim.