Research Note

New observations of chromospheric and prominence activity on the RS CVn-type binary SZ Piscium

¹ National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011, PR China
e-mail: dtcao@ynao.ac.cn
² Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650011, PR China
³ Graduate University of Chinese Academy of Sciences, Beijing 100049, PR China

Received: 30 September 2011
Accepted: 23 December 2011

Abstract

Aims. New high-resolution spectroscopic observations were made for the RS CVn-type binary SZ Psc aimed at searching for evidence of stellar prominences in this system and studying its chromospheric activity.

Methods. By means of the spectral subtraction technique, we searched for prominence-like events in the H_α spectra, and also analyzed several optical chromospheric activity indicators (the He   i D₃, Na   i D₁, D₂, H_α, and Ca   ii IRT lines) included in our observations.

Results. The emission in the H_α and Ca   ii IRT lines show that the cooler component is very active, supporting earlier work. Notably, some absorption features are detected in the subtracted H_α profiles, and one of them may result from prominence-like material on the cooler component of the system. According to a model of stellar prominences, the distance of the prominence from the rotation axis of the cooler component is calculated to be close to the corotation radius and to exceed the Roche lobe of the cooler component.