2008A&A...487..709Z

We present the new high-resolution echelle spectra of SZ Psc, obtained in Nov. 2004 and Sep.-Dec. 2006, and study its chromospheric activity.By means of the spectral subtraction technique, we analyze our spectroscopic observations including several optical chromospheric activity indicators (the HeI D₃, NaI D₁, D₂, H_α, and CaII infrared triplet lines). All indicators show that the chromospheric activity of the system is associated with the cooler component. We find that the values of EW₈₅₄₂/EW₈₄₉₈ are in the range 1-3, which indicates optically thick emission in plage-like regions. The 2006 data suggest the presence of active longitude phenomena. For the CaII 8542 and 8662 and the H_α lines, it seems that the excess emission is stronger near the two quadratures of system. This may be anti-correlated with the behavior of the NaI D₁ line. The absorption features are detected in the subtracted H_α lines, which could be explained by prominence-like extended material seen on the stellar disk or by mass transfer from the cooler component to the hotter one.