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We present time-series Doppler images of the rapidly-rotating active binary star EI Eri from spectroscopic observations collected during the MUSICOS multi-site campaign in 1998, since the critical rotation period of 1.947 days makes it impossible to obtain time-resolved images from a single site. From the surface reconstructions a weak solar-type differential rotation, as well as a tiny poleward meridional flow are measured.
We present Doppler Images of the RS CVn binary system HR 1099 (V711 Tau) from spectra taken in two different sites, KPNO and MSO, during the MUSICO S 1998 campaign. Contemporaneous APT photometry is used to constrain the Doppler Images. The resulti
We present simultaneous and continuous observations of H_alpha, H_beta, NaI D_1, D_2, HeI D_3 and CaII H & K lines of the chromospherically active binary HR 1099. We have observed HR 1099 for more than 3 weeks almost continuously and monitored two fl
We present simultaneous and continuous observations of H_alpha, H_beta, NaI D_1, D_2 and HeI D_3 lines of the chromospherically active binary HR 1099. We have observed HR 1099 for more than 3 weeks almost continuously and monitored two flares. An inc
We present simultaneous and continuous observations of the H$alpha$, H$beta$, He {sc i} D$_{3}$, Na {sc i} D$_{1}$,D$_{2}$ doublet and the Ca {sc ii} H & K lines for the RS CVn system HR 1099. The spectroscopic observations were obtained during the M
We present new Doppler images of both components of the double-lined binary $sigma^{2}$ CrB, based on the high-resolution spectroscopic data collected during 11 nights in 2015 March--April. The observed spectra form two independent data sets with suf